REPORTTOTHESURGEONGENERAL U. 5. PUBLIC HEALTH SERVICE ON PROTECTING AND IMPROVING HEALTH THROUGH THE RADIOLOGICAL SCIENCES PREPAREDBY THE NATIONAL ADVISORY COMMITTEE ON RADIATION APRIL 1966 U. S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE Public Health Service National Advisory Committee on Radiation Membership -----_-__-___-- Summary and Recommendations -_- _____-___-__-__ -__-_--_-__--__-- Introduction ~__~-_~-__--_---~--_____________________~--~~~~-~~~-- Historical Review of the Radiological Sciences ______ -__----__- ______ -- Developing Role of PHS in Uses and Control of Ionizing Radiation ______ (a) Scope of the Radiological Sciences ---__-__----_---_--_------ (b) Benefits and Risks of Ionizing Radiation _---_-__-- __________ ~ (c) Relationship of PHS to State and Local Health Agencies ________ (d) Radioactive Contamination of the Environment _--__-________ (e) Medical Applications of Ionizing Radiation --_--_---_-___-__-- Manpower Shortages and Related Academic Problems in the Radiological Sciences _---_--_--_---------_________ ______ -_ (a) Growth in Clinical Demand for Radiological Service __________ (b) Growth in Physician Manpower in the Radiological Sciences --~- (c) Future Needs in Physician Manpower in the Radiological Sciences (d) Causes of Physician Manpower Shortages in the Radiological Sciences ____-__-___-____________________________------~-- (e) Current Trends in Academic Radiology ---_-----_--_-___----- (f) Other Manpower Needs in the Radiological Sciences -_-------_~ (g) Correction of Manpower Shortages in the Radiological Sciences -- PHS Program Development in the Radiological Sciences _--_---------_~ Restatement of Recommendations __--_..--_---_--_--_--------------- Bibliography .~_--__- _.______ -__-__-_-_-- _____ -__--___- ____ --__---__ Page iv 7 7 11 13 13 18 19 20 24 26 27 . . . 111 NATIONAL ADVISORY COMMITTEE ON RADIATION DR. RUSSELL H. MORGAN, Chairman Radiologist-in-Chief Johns Hopkins Hospital 601 North Broadway Baltimore, Maryland DR. JOHN H. BARR DR. LEON 0. JACOBSON Professor of Radiology Prof. and Chairman Dept. of Medicine Tufts University University of Chicago 136 Harrison Avenue 950 East 59th Street Boston, Massachusets Chicago, Illinois DR. CYRIL L. COMAR Head, Dept. of Physical Biology New York State Veterinary College Cornell University Ithaca, New York DR. ROSCOE P. KANDLE State Commissioner of Health State of New Jersey Dept. of Health Box 1540 Trenton, New Jersey DR. RALPH E. DWORK Deputy Secretary of Health Pennsylvania Department of Health State Capitol Health and Welfare Building Harrisburg, Pennsylvania DR. LAURENCE L. ROBBINS Radiologist-in-Chief Department of Radiology Massachusetts General Hospital Boston, Massachusetts DR. J. NEWELL STANNARD Prof. of Radiation Biology & Assoc. MR. ALEXANDER GRENDON Donner Laboratory University of California Berkeley, California Dean for Graduate Studies University of Rochester School of Medicine and Dentistry 260 Crittenden Boulevard Rochester, New York DR. HERMAN E. HILLEBOE Columbia University School of Public Health & Administrative Medicine 600 W. 168th Street New York, New York DR. ARTHUR C. UPTON Chief, Pathology and Physiology Sect. Biology Division Oak Ridge National Laboratory Oak Ridge, Tennessee DR. RUSSELL I. PIERCE, Exec. Secretary Chief, State Assistance Branch Division of Radiological Health, BSS U.S. Public Health Service Washington, D.C. iv This is the third in a series of reports pre- pared by the National Advisory Committee on Radiation for the Surgeon General of the Public Health Service. The first two were directed to the broad responsibilities of the Service in the field of radiation control and to problems con- cerned with the protection of the public against undue radiation exposure from contamination of the environment ,with radioactive materials. In this report the Committee traces the remark- able growth that has taken place in the uses of ionizing radiation in the health professions, in industry, and in other walks of life. It also notes a number of emerging problems which not only are of importance from the point of view of radiation protection, but also, if not alleviated, threaten the quality of medical care in the United States and the translation of the advances of atomic research into needed bene- fits for the people. These problems include (a) serious weaknesses in academic departments of radiology which have restricted efforts to provide adequate instruction of medical and post-doctoral students in the clinical applica- tions of ionizing radiation, including radiation protection ; and (b) an increasingly severe shortage of manpower in all branches of the radiological sciences. The magnitude and com- plexity of these problems are sufficiently great that a concerted effort is needed by the Public Health Service to correct them. The alleviation of the problems just cited is but a part of a more comprehensive series of responsibilities faced by the Service in the radiclogical sciences. The Service must play an important role in the prevention of undue ex- posure of the population from medical, occupa- tional, and environmental sources of ionizing radiation; at the same time, it must actively support the development and application of radiologica1 methods in the diagnosis and treat- ment of diseases. In order that the Service may effectively meet its enlarging responsibilities in the radiological sciences, the Committee in this report makes a number of recommendations to the Surgeon General and urges that he take appropriate steps for their early implementa- tion. For convenience, these recommendations are summarized as follows: 1. The Public Health Service should take im- mediate steps to strengthen its programs in the radiological sciences by unifying their adminis- trative direction. Such action is needed to assure an orderly dcvelopmenr; of the broad spectrum of radiological activities for which the Service is responsible and to give continu- ous attention to the balance of benefit and risk in all matters pertaining to the human applica- tion of ionizing radiation. 2. The Service should undertake the follow- ing training and research and development pro- grams to upgrade the quality of the radiological services which have become such a critical part of medical and dental care and to improve radiation protection practices in the health professions : (a) a series of training programs : (i) to strengthen radiological instruction of medical students; (ii) to increase the number of academic radiologists in American medical schools; and (iii) to increase the number of practicing radiologists in the United States. (b) a series of training programs to pro- vide increasing numbers of radiochemists, radiological engineers, radiobiologists, radio- logical physicists and radiological health specialists. (c) a series of training programs to pro- vide increasing numbers of technologists in the several disciplines of the radiological sciences. (d) a series of applied research and devel- opment programs to increase the effective- ness and safety with which radiological pro- cedures are employed in the health professions. V (e) a series of programs to provide train- ing and research facilities for academic de- partments of radiology in American medical schools. 3. The Service should take the initiative in the formulation and promulgation of (a) stand- ards deaIing with the qualifications of person- nel who operate x-ray equipment or who use radioactive materials not regulated by the Atomic Energy Commission; (b) design stand- ards for sources containing radium and other radioactive materials that are not reactor by- products; and (c) standards for the premarket- ing clearance of x-ray equipment used in the health professions and in industry. 4. The Service should take appropriate action to assure that official health agencies play an increasingiy prominent role in the appraisal of the health risks associated with the construc- tion and operation of major nuclear facilities. 5. The Service should take immediate steps to strengthen its laboratory and statistical re- sources in the radiological sciences. These re- sources are essential components of the PHS effort to meet the Surgeon General's responsi- bilities to the nation. 6. If needed, appropriate legislative authority should be sought at the earliest possible time to carry out the foregoing recommendations. Vi Protecting and improving Health Through The Radiological Sciences I. Introduction In recent years, the radiological sciences have exerted an ever-increasing influence on the lives of the American people. In the field of medicine, more than half of the population is subjected each year to radiological study, either through the use of x rays or the ad- ministration of radioactive materials during the diagnosis and treatment of their disease. In industry and many other walks of life, radio- logical methods which protect the people from undue exposure to ionizing radiation have made possible the realization of many of the great benefits of the atomic age. In the future, the radiological sciences are likely to play an even greater role in society. Markedly expanded medical services, intimately involving radiological methods, are being made available to the public. And, further advances in atomic energy will require the careful evaluation and application of protective meas- ures if these advances are to yield their maxi- mum usefulness. In view of these circumstances, the National Advisory Committee on Radiation believes it timely that a review of the responsibilities of the Public Health Service in the radiological sciences be undertaken. This is particularly so in view of the recent emergence of a number of problems which if allowed to continue may seriously hamper such programs as Medicare and the nation's efforts to combat cancer, heart disease and stroke. Furthermore, additional problems are making more difficult the trans- lation of the advances of atomic research into needed benefits for the public. In this Report, the Committee has made an effort to identify these problems and to propose a series of rec- ommendations which may be helpful to the Surgeon General in bringing about their early resolution. II. The Development of the Radiological Sciences- A Short Historical Review To place the discussions of this Report in perspective, the following history of the growth and development of the radiological sciences has been prepared. Although brief, it provides background information which may assist the reader in gaining a better under- standing of the complex interrelationships pre- vailing in the nation's use and control of ioniz- ing radiation. The radiological sciences had their origin in November, 1895, when Wilhelm Conrad Riintgen, professor of physics at the University of Wiirzburg, Germany, discovered "a new kind of rays" which he subsequently called "x-rays". There are few scientific discoveries in the history of mankind that have generated scientific and public reaction so immediate and so great. The possibility of using x-rays in medical and surgical diagnosis was recognized at once. Within the first year after the an- nouncement of the discovery almost one thousand scientific papers and many textbooks on x rays were published. In February of 1896 the Journal of the American Medical Associa- tion expressed the cautious opinion that x-rays might be useful in the treatment of disease. From the early applications of x-rays in med- ical diagnosis, the branch of the radiological sciences now kncswn as diagnostic roentgen- olog~ developed. Simultaneously, the use of x- rays in the treatment of disease gave birth to the clinical specialty of radiatio,n therapy. Medicine was, of course, not the only scien- tific discipline to benefit from Riintgen's dis- covery. The natural sciences also profited at once. One of the most important consequences was the discovery of radioactivity by Becquerel in 1896, soon to be followed by the discovery of radium by Marie and Pierre Curie in 1898. 1 The discoveries of RGntgen, Becquerel and productive cells produce changes or mutations the Curies were the forerunners of seven in succeeding generations of the irradiated decades of brilliant scientific achievement. In species. 1905, Einstein proposed that mass and energy are related by the now well-known equation, Between 1934 and 1940, several hundred E = me', in which E signifies energy, m mass, artificially created radionuclides were discov- and c the velocity of light. In 1911, Rutherford ered. Use of these materials in medicine led to proposed an atomic theory in which he sug- the birth of the clinical discipline now known gested that the mass and positive charge of the as 7lliclea~ ~eclici72e. atom are concentrated in a central nucleus. And In 1939, Hahn and Strassman bombarded in 1913, Bohr proposed an atomic model com- uranium-235 with neutrons and demonstrated prising a central nucleus with electrons moving the phenomenon of nuclear fission, a process in in systematic orbits about it. Although modified which each uranium atom broke into two ap- considerably in later years, this model was of proximately equal parts. The process was ac- great value in guiding research in the physical companied by the liberation of neutrons and the sciences at the time. release of substantial amounts of energy. In 1919, Rutherford found that the nuclei of Hence, work was begun to devise an experiment nitrogen atoms under certain experimental in which uranium could be made to undergo conditions of bombardment yielded positively fission in a self-maintaining, controlled reac- charged particles which he named protons. He tion. In December, 1942, this culminated in the also observed that in this process the nitrogen development of the first successful uranium atoms were transformed into oxygen. This was pile or reactor at the University of Chicago. the first experiment in which one element was The work at Chicago raised the curtain on the artificially transformed into another. In the atomic age. The reactor made possible the pro- next year, Rutherford proposed that atomic duction of large amounts of radioactive mate- nuclei also include a fundamental particle ap- rials which soon found widespread use in proximately the size of the proton but bearing research and development in industry, agricul- no electrical charge. This particle he named the ture and medicine. It ushered in the era of neutron. Twelve years later, Chadwick dis- power from nuclear sources. And it made pos- cover~l the existence of this particle and in sible the production of atomic weapons of un- 1934, Fermi, while bombarding uranium and precedented magnitude. other atoms with neutrons, observed many phenomena of artificial transmutation and After the end of World War II, it was con- radioactivity. fidently predicted that the enormous advances Simultaneously with the work in the physical which had taken place in the natural sciences sciences, a number of investigators began to since Riintgen's discovery would bring untold study the biological effects of x rays and of the benefits to all mankind. Spectacular develop- radiations emitted from radium. Quite acci- ments in the diagnosis and treatment of disease dentally in the early part of this century it were anticipated. The provision of unlimited was discovered that some physicians who used amounts of cheap electric power for every x rays in the diagnosis of their patients de- nation in the world seemed possible. And the veloped inflammatory changes of the skin of application of the nuclear sciences to a vast their hands, changes which not infrequently array of industrial and agricultural processes became cancerous. These effects were traced to appeared likely to open up a great new period the practice of these physicians of placing their of technological development and economic hands under their fluoroscopes each day while progress. they tested the operational characteristics of For some time, these promises were un- their equipment. realized ; progress was disappointing. How- The damage done to the hands of the pioneer ever, if an error was made in assessing the radiologists was due to relative!y large doses of impact of the atomic age on society, it was an x rays. Late in the 1920's Jluller discovered error of timing rather than of substance. Re- that relatively small doses of radiation to re- cently, progress has been accelerating. Nuclear 2 medicine has reached a stage of development where the number of patients examined by this method is doubling every three to five years. In industry and agriculture, the applications of radioactive materials are expanding rapidly. Xnd nuclear power reactors are being planned ;lt a rate such that one may expect a substantial fraction of the electric power generated in the United States will come from these installations within the next few decades. There can now be no question that atomic development will exert a substantial and continuing influence on so- ciety in the years to come. 111. The Developing Role of the Public Health Serv- ice in the Uses and Control of Ionizing Radiation (n) The Scope of the Radiological Sciences The sum of systematized knowledge pertain- ing to the application and control of ionizing radiation is the province of the radiological sciences. From a health standpoint, the radio- logical sciences of greatest interest are those concerned with the uses and control of ionizing radiation in medicine, dentistry and their re- lated disciplines and those pertaining to the control of such radiation in industry, agricul- ture and the environment. In this report, the radiological sciences, for purposes of discus- sion, have been divided into the following categories : I. CLINICAL SCIENCES 1. Diagnostic Roentgenology : the use of x- rays in the diagnosis (recognition and evalua- tion) of disease. 2. Radiation Therapy: the use of ionizing racliation, including that produced by x-ray machines, particle accelerators and radioactive materials, in the treatment of disease. 3. Nuclear Medicine: the use of radioactive materials in the diagnosis of disease. By custom, diagnostic. roentgenology, radia- tion therapy and nuclear medicine are often collectively referred to as radiology. II. COMMUNITY HEALTH SCIENCES (PUBLIC HEALTH DISCIPLINES) 1. Radiological Health: the prevention of un- due exposure of the population from ionizing radiation and the use of such radiation in the Preservation and betterment of public health. 2. Health Physics: the use of physical meth- ods in the protection of man and his environ- ment from unwarranted radiation exposure. III. LABORATORY SCIENCES 1. Radiobiology: the study of the biological effects of ionizing radiation and the use of such radiation in the investigation of fundamental biological phenomena. 2. Radiochemistry: the branch of chemistry dealing with radionuclides and their properties, with the use of radionuclides in the study of chemical problems, and with the behavior of minute quantities of radioactive materials de- tected by means of their radioactivity. Impor- tant to medicine are: ( i) clinical applications : the development and production of radionuclide-labelled com- pounds for pharmaceutical and biochemical use; and (ii) analytical applications: the assay by chemical processes of the radioactive consti- tuents of compounds and contaminants. 3. Radiological Engineering: the design, de- velopment and utilization of radiological in- struments, materials and apparatus. 4. Radiological Physics : the study of physical problems related to the applications of ionizing radiation in clinical medicine. (.!I) The Ben,efits and Risks of Ionizing Ra- diation With the increasing complexity of modern living, the medical, social and economic needs of the individual and of his family have become closely related. Hence, when health planning is undertaken, consideration must be given to the results of such planning on the social and eco- nomic development of the nation. This is especially true in the radiological sciences. The applications of radiation hold great and sub- stantial benefits to mankind. However, the at- tendant human exposure which may accompany many of these uses poses a number of health risks. It is therefcre clear that health planning in the radiological sciences requires the most careful balancing of benefit against risk if medical, social and economic progress is to take place. Failure to make such plans may lead to economic stagnation in the atomic sciences if 3 health regulations are too restrictive or too serious dangers to the public health if these regulations are inadequate. As new developments in the atomic sciences have unfolded, and as the uses of ionizing ra- diation have become more extensive, the Public Health Service has found it necessary to under- take an increasing number of activities in the radiological sciences. These efforts may be con- veniently divided into two interdependent parts : 1. Activities concerned with the control of the incidental radiation exposure received by the population from radioactive contamination of the environment and from occupationally related sources ; and 2. Activities concerned with the intentional application of ionizing radiation in the preven- tion, diagnosis, treatment and after-care of diseases, injuries and congenital defects. The responsibilities of the Public Health Service in the field of radiation control were broadly outlined in a report to the Surgeon General by this Committe in 1959(l). In this report the Committee urged the Service to assume a major role both in the formulation of national policy and the initiation of compre- hensive programs in the control of ionizing radiation in the United States. It proposed that the Service take steps leading to its active par- ticipation in (1) the formulation of radiation standards ; (2) the training of radiological health specialists ; and (3) the development of regulatory programs for the protection of the public from all sources of ionizing radiation. There was particular concern for the prevention of undue exposure from radioactive contami- nation of the environment, from radiation sources used by the health professions and from industrial and other sources contributing to occupational exposure. In accordance with this report, the Service has established a series of nationwide surveil- lance networks to monitor environmental con- tamination. It has supported university pro- grams to train radiological health specialists. It has also undertaken a broad range of activi- ties designed to reduce unnecessary exposure from medical and dental sources of radiation. In the field of occupational exposure, efforts so far have been relatively limited and much more remains to be done. The place of the Public Health Service in the formulation of radiation standards was clearly defined late in 1959 by the creation, first by Executive Order and then by Public Law 86- 373, of the Federal Radiation Council. This agency was given responsibility to advise the President on all matters directly or indirectly affecting health, including guidance to federal agencies on the formulation of radiation stand-. ards. The Council includes the heads of six De- partments of the United States Government, each having a major interest in the applications and control of ionizing radiation. Through the Department of Health, Education and Welfare, one of the participating agencies, the Public Health Service has made important contribu- tions to the deliberations of the Council. The FRC has been ably assisted in its work by the National Academy of Sciences to which it turns for guidance in matters pertaining to the biological effects of ionizing radiation. It has also had enormous help from the National Council on Radiation Protection and Measure- ments. This organization, composed of leading scientists, has for over three decades taken the initiative in setting detailed technical standards designed to protect the individual and the pop- ulation as a whole from ionizing radiation. The FRC, with the NAS and NCRP, provides broad supervision of radiation standards in the United States. In general, the FRC has not as- sumed responsibility for the development of operational standards pertaining to specific radiation problems. The formulation and pro- mulgation of such standards have been left to those federal, state and local agencies which by law are responsible for the registration and licensing of radiation sources. For example, the Atomic Energy Commission has established a system of technical and professional criteria governing the use of reactor-produced radio- nuclides. Also, an increasing number of states, mainly through their departments of health, have established technical standards for all sources of ionizing radiation. It is noteworthy that although these standards are being for- mulated in many places, they are remarkably uniform throughout the country because of the guidance'provided by the FRC and NCRP. 4 Although the development of radiation stand- ards in the United States is progressing satis- factorily, this Committee observes a number of gaps which require careful attention in the years immediately ahead. One of these is the absence of standards relating to the qualifica- tions of technical and professional personnel using radiation sources other than those reg- ulated by the Atomic Energy Commission; that is, medical x-ray machines and sources con- taining radioactive materials that are not reactor by-products. This Committee believes that such standards must be established to assure the public that those who use ionizing radiation are well trained and qualified. It fur- ther believes that the Public Health Service, as the principal government agency responsible for the health of the nation, should take the initiative in the formulation of these standards and should seek the coooperation of the health professions in this undertaking. Another gap is the absence of design stand- ards for radiation sources containing radium and a number of other radionuclides not now regulated by the AEC. Since these sources are frequently the cause of hospital and environ- mental contamination, the Public Health Serv- ice should take early steps to formulate and promulgate appropriate standards for these sources. In assuming this responsibility, the Service should take full advantage of the ex- perience of the AEC, gained in developing sim- ilar standards for the sources under its juris- diction. A third gap concerns radiation standards for x-ray equipment used in medicine and den- tistry. Although basic standards in this field have already been formulated by the NCRP, there is need for a series of standards which may be used as a basis for the premarketing clearance of x-ray equipment. If such standards can be developed in association with a program of premarketing clearance, efforts to reduce unnecessary radiation exposure in the health professions will be materially facilitated. (c) The Relationship of the Public Health Service to State and Local Health Agencies The Public Health Service, in developing its role in the radiological sciences, has encouraged state and local health departments to assume major responsibility for the control of ionizing radiation. This is consistent with traditional patterns in public health. Except under special circumstances, the Service has for many years operated within a policy which restricts its own activities in the control of health hazards to those requiring a national effort ; e.g., to the development of health standards and to certain laboratory and technical operations which are best performed at the federal level. Regulatory activities, including the licensing of hazardous agents, the inspection of facilities involving health risks and the application of counter- measures to correct health problems, have gen- erally been left to state and local health au- thorities to administer. The policy is based on the belief that such authorities are usually most familiar with the resources that can be brought to bear on health problems as they arise. In recent years, the Public Health Service has given moderate amounts of financial SUP- port to many state and local health departments for the development of their radiation control programs. Concurrently, many states have adopted laws which give their health depart- ments authority to undertake major responsi- bility for the control of ionizing radiation. Moreover, recent changes in the Atomic En- ergy Act(z) have permitted the AEC to begin transferring much of its responsibility for the control of by-product materials to the states. The assumption of regulatory authority over radiation sources by the states has not been without its problems. Some states after pro- viding their health departments with authority in the field of radiation control have been unable or unwilling to give the funds needed by these departments to perform effectively. Although some states have provided well, adequate re- sources have not been generally made avail- able to maintain registration and licensing rec- ords and to carry out regular systematic in- spections. As the use of ionizing radiation in medicine, industry and other walks of life grows, these inadequacies are becoming in- creasingly serious. Hence, the Public Health Service must remain alert to the dangers in- herent in this situation and take appropriate steps to fill the gaps in the nation's program of radiation control whenever necessary. (d) Radioactive Contaminution of the En- vironment In 1962, this Committee identified a number of public health problems concerned with ra- dioactive contamination of the environment(3). It reaffirmed that the Service has major re- sponsibility to maintain appropriate surveil- lance networks to provide continuing informa- tion on levels of environmental contamination affecting the public. It also emphasized the need for the Service to undertake broad re- search programs to develop countermeasures for the control of environmental contamination. Substantial progress has been made in both of these areas. Although the nuclear weapons test ban appeared to reduce the need for environ- mental surveillance for a time, current world conditions make a continuing effort in this field essential. Furthermore, as major nuclear facil- ities for industrial and other peaceful uses be- come more widespread, the Service's surveil- lance capability will have increasing value. In connection with the development of major nuclear facilities in the United States, the Com- mittee notes a continuing problem which might well be alleviated by appropriate action on the part of the Public Health Service. As state and local health departments have assumed an in- creasing role in the control of ionizing radia- tion, the Atomic Energy Commission has quite properly retained responsibility for the licens- ing of major nuclear facilities. Such facilities involve potentials for contamination which are interstate in extent and hence require a cen- tral regulatory authority. Notwithstanding the basic wisdom of this policy, this Committee observes a continuing apprehension on the part of the public when new nuclear facilities are contemplated. It be- lieves that this is unfortunate for it not only postpones the day when the public is able to share in the many benefits provided by the nuclear sciences but it also engenders fears which are costly in terms of public health. To help solve this problem, competent health au- thorities should play a more prominent role in the consideration of public health factors af- fecting the construction and operation of ma- jor nuclear facilities. Not only is the advice of such authorities essential from the standpoint of the health risks of people working and resid- ing in the vicinity of the facility, it is important that authorities having no official responsibility for the promotion of a nuclear facility play a substantial part in the judgments that must be made when the facility is proposed. This problem is likely to become increas- ingly serious in the years ahead. At present, only a small fraction of the nation's electrical power is produced by nuclear facilities. How- ever, in the next few decades, demands for electrical power from nuclear sources are likely to increase as the relative amounts of fossil fuels decrease. It therefore appears impera- tive that public health authorities henceforth play an important role in matters pertaining to the construction and operation of major nu- clear facilities. The health risks involved in any proposed major nuclear facility require. the independent appraisal by official health agencies. I - (e) Medical Applications of Ionizing Radi- ation In foregoing discussions, attention has been directed to certain gaps in programs to pro- tect the public against undue radiation expo- sure. A number of problems have been iden- tified and solutions for them proposed. These problems have not been discussed in depth be- cause the Committee wishes to direct its major attention in this Report to a series of problems concerned with the uses of ionizing radiation in the health professions. These problems re- late to weaknesses in the teaching of the clin- ical application of ionizing radiation, includ- ing radiation protection, which have resulted from manpower shortages. It is appropriate that these matters receive intensive review at this time. New health pro- grams (Titles 18 and 19@) and the program for cancer, heart disease and stroke) proposed by the President and approved by Congress are likely to place increasing strain on the ra- diological manpower and teaching resources of this nation in the years ahead. Concern for these problems has recently been voiced in a report by the Committee on Appropriations of the United States Senate under the chairman- shin of Senator Pastore(5). 6 IV. Manpower Shortages and Related Academic Problems in the Radiological Sciences Although the radiological sciences had their origin only a little over a half century ago, their importance to medicine and dentistry has grown with unusual rapidity. A recent study by the Public Health Service@) has shown that in 1960-61 over 89 million medical and 48 mil- lion dental x-ray examinations were carried out annually in the United States. This repre- sents on average the performance of one med- ical examination for every two individuals in the population each year and one dental ex- amination for every four. Such a demand for clinical service clearly indicates that the radio- logical sciences in the short space of seventy years have become one of the major disciplines of American medicine, exerting a substantial and continuing influence on the care of every man, woman and child. The spectacular growth of the radiological sciences in the health professions has not been without its problems. Indeed, such growth is responsible for the recent development of a serious shortage of professional and techni- cal personnel which threatens the quality of medical care as well as the success of many of the government's health programs. These short- ages are particularly evident in academic de- partments of radiology where they have re- stricted efforts to provide adequate instruction of medical and post doctoral students in the clinical applications of ionizing radiation in- cluding radiation protection. The magnitude of this problem may perhaps be best illustrated by a comparison of growth patterns in demand for radiological service which have developed in recent years with corresponding growth pat- terns in radiological manpower. (a) Growth in clinical demand for radiolog- ical service In the diagnostic roentgenology, the disci- pline concerned with the use of x-rays in the diagnosis of disease, the demand for clinical service is reflected in part by the annual con- sumption of medica x-ray film. This is because such film plays a basic role in the performance of almost every x-ray examination. Annual consumption data for medical x-ray film in the United States from 1947 to 1963 are shown in figure 1. During this time, film consumption increased at an average annual compounded rate of almost 5.4 percent. While these are impressive data, denoting a doubling of consumption every thirteen years, they do not indicate the total growth that has taken place in the demand for diagnostic x-ray service. Since World War II, advances in med- ical research have caused the emergence of im- portant new roentgenological methods which have added clinical demands largely unreflected by film consumption data. These methods are the outgrowth of two technological innovations occurring in the early 1950's ; the first was the development of instrumentation by which fluo- roscopic images can be amplified in brightness many thousands of times. Prior to this, physi- cians working in the field of diagnostic roent- genology were restricted in their use of x-rays to relatively simple examinations. More com- plicated procedures requiring prolonged fluo- roscopy and the recording of radiological data on motion picture film were quite impractica- ble because excessive amounts of radiation were needed with techniques then available. The de- velopment of fluoroscopic amplification changed all this and and a new era of diagnostic roent- genology began. The second technological in- novation was the development of the rapid film- changer, a device with which large numbers of radiographic exposures can be made in quick succession to provide a detailed record of rap- idly occurring events. Together, the fluoroscopic amplifier and the rapid film-changer have made possible the de- velopment of an increasing number of complex radiological procedures of fundamental impor- tance in the diagnosis of many diseases. Some of the more noteworthy of these include angio- cardiography, a procedure which permits the physician to study in detail the structure and physiology of the heart and its great vessels; cerebral arteriography, a method devised for the intensive investigation of the circulation of the central nervous system; and cinefluo- rography, a procedure using x-ray motion pie- ture techniques to evaluate abnormal anatom- ical and physiological states in a broad range of body systems. 7 FIGURE l-Index of medical x-ray film consumption. This index has been calculated from data on the gross square footage of x-ray film produced annually in the United States, less film diverted for industrial and dental uses and adjusted for film exported and imported. 3009 250- 200- 150- IOO- so- INDEX OFANNUAL MEDICAL X-RAY FILM CONSUMPTION IN U.S. (1947= 100) .- - 1965 1955 YEAR FIGURE I. 1960 One of the most important characteristics of these new methods is that they need much more time and effort for their performance than do older, more conventional techniques. Indeed, they have a great deal in common with major surgical procedures, requiring for each exam- ination considerable numbers of highly trained professional and technical personnel and large outlays of special roentgenological and physio- logical equipment. In most instances, only two or three of these special examinations may be completed in one day by one team of workers. The benefits of these new methods are sub- stantial, particularly to those patients with cardiovascular and neurological diseases. How- ever, it must be recognized that they place an unusually heavy burden on radiological man- power. Data which give a measure of this burden have been unavailable heretofore. Hence, the Committee undertook a study based on the rec- ords of a random sample of 17 large, univer- sity hospitals *, widely distributed throughout the United States, to obtain this information. Six of the hospitals were in the eastern part of the country, six in the midwest, three on the west coast and two in the south. In this group of institutions, over 1.31 million diagnostic x- ray examinations, including 37.2 thousand spe- cial roentgenological procedures, were per- formed by an aggregate professional staff of 177 radiologists during the year 1964. The equivalent of 44 radiologists was needed for the special examinations. Although the institutions included in this study are not entirely repre- sentative of all hospitals in the United States, they are perhaps sufficiently so that the follow- ing conclusions may be drawn: 1. The number of special examinations currently performed is relatively small, amounting to less than 3% of all examinations undertaken, and has little influence on film consumption statistics. 2. These examinations, on the other hand, are suf- *Massachusetts General Hospital. Boston: New York Hospital, New York: Presbyterian Hospital. New York; University of Penn- #ylvania Hospital. Philadelphia; Johns Hopkins Hospital. Baltimore; Strong Memorial Hospital, Rochester, New YorL; University Hos- pit& of Cleveland: Ohio State University Hospital. Columbus: Cincinnati General Hospital. Cincinnati; Billings Hospital, Chicago; Indiana Universitv Medical Center. Indianapolis: Universitv of Minnesota Hospit&. Minneapolis: En&y University Hos&al. Atlanta: John Se& Hospital. Galveston; University of California Hospital. Los Angeles: University of California Hospital, San Fran- cimo: and the A5hted University Hospitala, Seattle. ficiently complicated and time-consuming that their performance absorbs about 25% of the professional manpower in diagnostic roentgen- ology. This suggests that film consumption at most reflects only three-quarters of the total demand for diagnostic x-ray service. Further- more, because the growth in special examina- tions has taken place largely in the past fifteen years, it suggests that the demand for roent- genological services currently is growing at a rate at least one-third greater than the 5.4% annual rate indicated by film statistics alone; that is, total demand is increasing at a rate in excess of 7.2%. In radiation therum, clinical demand is re- lated to the frequency of occurrence of cancer because this method of treatment has been re- served more and more for patients with malig- nant neoplasms. For several decades, the num- ber of persons having cancer has increased as the population has become larger and as more individuals have lived to %advanced age when cancer is more common. Recently, cancer deaths have been rising at an annual rate of about 270, as shown in figure 2tT), where data on the number of deaths per year from cancer of all sites in ten states and the District of Colum- bia are given for the period from 1936 to 1960. It seems likely that the increase in clin- ical demand for radiation therapy has at least equaled this rise. In nucleur medicine, the branch of the radi- ological sciences which pertains to the applica- tion of radioactive materials to the diagnosis of disease and to the study of physiological processes in man, the demand for clinical serv- ice is difficult to evaluate. Such demand is not reliably reflected by amounts of radioactive materials produced for medical use because diagnostic applications of nuclear medicine, re- quiring relatively small individual quantities of these materials, are growing at a much faster rate than therapeutic procedures, for which large quantities are needed@). The number of persons licensed to use radioactive materials for medical purposes also is not a reliable index of the demand for clinical service because the number of examinations performed each year is increasing much more rapidly than the num- ber of licensees. In the 17-hospital study car- 9 FIGURE 2-Numbers of deaths per year from cancer of all sites in ten states and the District of Columbia (7). I00,000 90,000 80,OO 0 60,000 50,000 40,000~ CANCER DEATHS PER YEAR (193% 1960) JII""l1"`l""j"`llll"ll"`l" 1935 1940 1945 1950 1955 1960 1965 YEAR FIGURE 2. 10 ried out by this Committee, data were collected which indicate that demand for clinical service has risen in the brief span of a few years to a level requiring more than one-tenth of the professional manpower devoted to clinical ra- diology (see table I). From a perusal of hos- pital records in a few institutions where pa- tient statistics in nuclear medicine have. been maintained for an adequate period of time, it is estimated that this discipline's clinical de- mand currently is growing at a rate of at least 15% per year. TABLE I-Distribution of Professional Staff, Arranged According to Radiological Discipline, in 17 University Hospitals. Radiological Number of Per Cent of Discipline Individuals Total Staff Diagnostic Roentgenology ------ 166 72.1 Radiation Therapy ----- -______ 35 16.3 Nuclear Medicine ----- --______ 26 11.6 TOTAL -------__-----________ 216 100 (b) Growth in physician manpower in the radiological sciences The growth in professional manpower avail- able in the clinical divisions of the radiological sciences is illustrated graphically in figure 3. These data, from statistics collected by the American Medical Association@), give the num- ber of radiologists in practice in the United States for the period of 1949 to 1964. It will be observed that the number of these special- ists grew from about 2,900 at the beginning of the period to more than 6,900 at the end, a compounded annual growth rate of 5.9%. At first glance, this growth seems remarkably good, substantially exceeding that of physicians in general. However, it falls considerably short of the growth needed to meet demands for clin- ical service as the following makes clear. Previous discussion has shown that the de- mand for diagnostic x-ray service for the last 15 years has grown at an annual compounded rate of 7.2% or more. In radiation therapy the o Thin mwth rate was calculated from the formula. G = PdDd + gtDt + BnDn where gd, gr and gn are the annual growth rates in demand for clin- ical service in diagnostic roentgenology. radiation therapy and nu- clear medicine respectively and pd, pt and pn are the PereentaSes of the total professional manpower presently engaged in the clinical radiological sciences which apply to the respective three divisions. In thi8 calculation. data for pd. pt and p,, were taken from table I. increase has been at least 2% per year and in nuclear medicine, 16% per year. Taken to- gether, after suitable weighting for the rela- tive manpower requirements of each of the three clinical divisions of the radiological sciences, these data indicate a composite com- pounded annual growth rate of 7.1%.* The foregoing data clearly indicate that in the years following World War II, growth in the clinical demand for radiological service has substantially exceeded the growth of physician manpower to meet this demand. An increasing manpower deficit of this sort must always be cause for concern. However, it is particularly disturbing in this instance because, for many years preceding the war, the training of med- ical specialists was sharply restricted due to the depression and thus even the number avail- able at war's end was inadequate. There can be little doubt then that there has developed in the radiological sciences a shortage of physi- cian manpower of serious ,proportions. This situation has been further aggravated by a recent change in attitude adopted by the medical profession toward the use of radio- logical methods in the practice of medicine. In the past, many physicians have employed x- ray machines in diagnosis and treatment even though their training in the use of these de- vices has often been limited. However, in the late 1950's, the profession became increasingly aware of the dangers of a physician's using ionizing radiation without his having had special training. The American Academy of Pediatricso"), for example, advised all pedia- tricians to discontinue fluoroscopy of their pa- tients whenever possible and to have their diag- nostic x-ray studies performed by radiography, where the radiation exposure is generally less. Because of this and similar recommendations from other groups, a substantial number of physicians not trained in the radiological sciences, but who have previously employed radiological methods in their practices, are dis- continuing their use. There can be little question that this action is desirable. However, its effects are to impose additional burdens on radiologists and to ag- gravate the shortage of trained manpower be- yond that indicated by the foregoing discussion. 11 FIGURE 3-Number of clinicril radiologists (less radiologists in training) practicing in the United States. lO,OOO- 9,00 o- &000- 7,000- 6,000- 5,000- 4,000- 3,000- 2,000- NUMBER OF CLINICAL RADIOLOGISTS (19494964) I I I I I I I I I I I I I I I I 1950 1955 1960 1965 YEAR FIGURE 3. i2 It is difficult to estimate precisely the mag- nitude of the physician shortage currently pre- vailing in the radiological sciences. However, the combined effect of all of the factors which have contributed to this shortage must be sub- stantial. Certainly, the deficit in manpower re- quirements amounts to many thousands of physicians. Indeed, it appears that the number of radiologists needed in the United States is almost twice as great as the number actually available. (c) Fwture needs in physician manpower in the radiological sciences In a field where the growth has been so inex- orable as in the radiological sciences, manpower shortages are likely to become worse with the passage of time. It is therefore important in health planning to examine future needs as well as to evaluate current problems. It is reasonable to assume that the growth patterns prevailing in the demand for radiological service over the past fifteen years will continue in the years ahead. Advances continue at a rapid pace in medical research. Large new programs of health care are in the process of development, and the public is demonstrating an increasing insistence on comprehensive medical care of high quality. If present growth rates in clinical demand continue, the need for physician manpower in the radiological sciences seems likely to rise to a level of three or more times current supply by 1975, i.e., to a level of from 20,000 to 25,000 radiologists in ten years. Such a need presents a disturbing picture to those responsible for the nation's health. It is clear that major attention must be given to the problems of radiological manpower as quickly as possible. The correction of manpower shortages de- pends in part upon the availability of potential resources. These resources include training fa- cilities, the supply of instructional personnel and supporting funds. Data on training positions in the clinical radiological sciences in the United States are shown in figure 4("). These depict the total number of hospital residency positions, both available and filled, for training radiologists from 1954 to 1963. It will be observed that the number of positions rose only slightly during this period from about 1,650 in the beginning to just over 1,950 at the end. Also, 24% of the positions remained unfilled on the average during this interval. In recent years, about 1,500 positions have been filled, including those occupied by foreign trainees. Because the length of residency training in radiology is nor- mally three years, the number of individuals completing their training each year is currently about 500. Death and retirement reduce this number to a net increase in radiological man- power of about 300 per year. If the present shortage of professional man- power in the radiological sciences is to be allevi- ated, almost 1,500 physicians must enter radiological training each year over the next decade ; that is, the current number who begin training must be increased threefold. Also, the number of training positions must be more than doubled to a level in excess of 4,500. It will be apparent to even the most optimistic that these goals are not likely to be attained. They require that over 20% of the medical students graduating each year enter radiologi- cal training. If this were to happen, it would almost certainly create serious dislocations in other branches of medicine. Therefore, to meet the increasing demands for radiological service, the nation must settle for more modest increases in the number of trainees and seek ways in which the available manpower in radiology may be used more effectively. Every modern educa- tional, administrative and technological means must be investigated to improve the efficiency with which radiological service is provided. Funds to support this type of radiological re- search must be given high priority. (d) Causes of physician manpower sho,?9ages in the radiological sciences Even partial correction of physician man- power shortages in the radiological sciences will be difficult. A full understanding of the causes of these shortages is necessary if success- ful methods to meet the problem are to be devised. One of the principal causes of difficulty, the unusual increase in demand for radiological services during the past several decades, has 13 FIGURE 4-Residency training positions for radiologists in the United States. m II NUMBER OF RADlOLOGY RESIDENCIES 4 OFFERED AND FILLED 20009 I800- 1600- 1400- m 1200- - I ooo- 800 ' ' I I I I I I I I I b 1954 1956 1958 1960 1962 1964 YEAR FIGURE 4. i4 been discussed. Another problem is the general shortage of physician manpower, which has affected all health professions in recent years. The number of graduates of medical schooIs in the United States has increased very slowly dur- ing the postwar period, from about 6,000 per year immediately following World War II to just over 7,300 in 1964(12j. This is barely equal to the growth rate of the nation's population during the same period and, in recent years, has been less (see figure 5). Such a rate is clearly insufficient to meet the increasing de- mands for medical service created by advances in medical research and by the expansion of services to lower income groups through vari- ous forms of insurance. To obtain more radio- logical trainees, therefore, it will be necessary, among other things, to take steps which will assure the graduation of more physicians each year from this country's medical schools. Although general manpower shortages in medicine are aggravating the personnel prob- lems of the radiological sciences, they by no means constitute the only or principal cause of difficulty, The percentage of unfilled residency training positions in radiology is among the highest of the major clinical specialties("). Of perhaps greater significance, the 17-hospital study undertaken by this Committee found that, of those who enter the clinical radiological sci- ences, only one quarter decide to do so when they are in medical school; of the remainder, half make their decision during internship and half after they have entered residency in some other medical specialty, private practice, or the military services (see table II). This is in sharp contrast to the experience of those enter- ing such specialties as medicine, surgery and pediatrics, where prevailing practices of selec- tion make it almost imperative for a prospective trainee to make his decision before graduation from medical school. The disproportionately large number of unfilled residency training po- sitions in radiology and the large number of trainees who decide to enter the specialty rather late in their careers, frequently as a sec- ond choice, indicate clearly that there are deep- seated troubles within the clinical branches of the radiological sciences themselves. TABLE II-Time at Which Physicians Decide to Make Radiology a Career. Data are from Study of Resident Staffs of 17 University HospitaIs in the United States during the year 1965. No. of Resident Radiolodsts Time of Decision Making Decision Per cent Before or During Medical School _ ____--------- 73 26 During Internship -- -________ -- 103 37 After Internship ..--- __________ 104 37 TOTAL --_-----_---__________ 280 100 These troubles are not difficult to find. One has only to examine the departments of radi- ology of American medical schools to discover that few are likely to attract many students to careers in the radiological sciences. Faculty time is largely devoted to the provision of radi- ological service to patients and to associated administrative functions. Little time is set aside for teaching, particularly at the predoctoral level, and much less for research. Under these circumstances, it is not surpris- ing that the medical student, before graduation, frequently finds little to interest him in radi- ology. To him, the clinical radiologist is a man whose time is wholly taken with routine clinical service, often given under conditions where doctor-patient relationships are rather distant, and hence, disappointing. Also, in his contact with the radiological faculty, in contrast to his experience in other clinical disciplines, the stu- dent sees little evidence of exciting research. Indeed, in many academic departments little or no research of consequence can be found at all. The student is aware of the radiologist's partici- pation in the many conferences and seminars he must attend ; but even here, it seems that the radiologist's role is quite subordinate, even though the information he provides is often decisive. In short, the radiological sciences do not present an inviting picture to most medical students. The paucity of experimental research in aca- demic departments of radiology may come as a surprise to many because the major advances which have taken place in this field could not have been achieved without substantial amounts of research by someone. An investigation, how- ever, shows that much of this research has been 16 FIGURE S-Number of physicians graduated from American medical schools each year per 100,000 population. 50 GRADUATING MEDICAL STUDENTS PER 100,000 POPULATION 45- (1940 - 1964) 0 0 a w 35 E z 1 30 2511'I"I"""""""""`- 1940 1945 I950 1955 1960 1965 YEAR FIGURE 5. 16 done by workers in other clinical disciplines. The reasons for this are perhaps twofold. First, the clinical service burden imposed upon the academic radiologist allows him little time for research. Second, and perhaps as important, the clinical radiologist, as American medicine is practiced today, does not have at his immedi- ate command one of the basic ingredients of clinical research, namely, patient material. If such a physician wishes to embark on a pro- gram of clinical investigation, it is usually necessary that he first stimulate the interest of a colleague in one of those clinical disciplines that have access to patients. If such interest can be aroused and if there are available facil- ities in which the work can be undertaken, only then can the research move forward. In most cases, facilities for radiological research are not available. In the great majority of the de- partments of radiology of American medical schools studied by this Committee, there is neither space nor equipment assigned for clin- ical investigation. Where research is being done, hospital x-ray facilities are used at odd moments when they are not employed for serv- ice functions, a situation which is often detri- mental to patient care as well as to research. The meagerness of the research effort, char- acteristic of academic departments of radiology in the United States, is well demonstrated by statistics pertaining to funds distributed by the Public Health Service, including the National Institutes of Health, for the training of re- search personnel.(1:5) During the fiscal year 1964, just under $170 million were allotted to medical schtiols and other research institutions for pre- and postdoctoral training grants and traineeships. Of this, only 1% went to academic departments of radiology. There can be little question that this represents an undesirably low level of support for a discipline which, as will be pointed out later, needs to attract close to one-tenth of the graduates of American medi- cal schools. The distribution of this support among the three clinical divisions of the radiological sci- ences is shown in table III. It is noteworthy that the funds made available to diagnostic roentgenology, the largest of the radiological divisions, amounted only to a little more than a half million dollars, or 0.3370 of all PHS train- ing funds. In nuclear medicine, funds for re- search training are also inadequate, amounting to approximately $200 thousand or a little more than 0.1% of all monies available. Even in radiation therapy, with support approaching $1 million, funds fell short of need. Data on the distribution of PHS funds for research indicate that the amount of support allotted to academic departments of radiology is also small. This is particuIarly so in diag- nostic roentgenology and nuclear medicine. This is not to say that radiological research is poorly supported by government. As previously indi- cated, substantial amounts of money have been made available for such research in depart- ments other than radiology. However, funds going to radiology departments are sharply limited. In discussing the shortcomings of academic radiology, the Committee has emphasized defi- ciencies in research because of the importance that research has assumed in American medical education during the past decade or two. Cog- geshall,oZ) in a recent report to the Association of American Medical Colleges, points out that .medical education has been going through a transition in which the emphasis has been transferred from the accumulation of facts, largely by memory, to a better understanding of the mechanisms involved in the development of normal tissues and their disease states. The research method has played an important role in this. Until now, experience in research in predoctoral years has been regarded as neces- sary only for those who intended to pursue sci- entific or academic careers. However, such experience is now considered essential to the education of the general practitioner and spe- cialist as well. Consequently, ample opportunity for student participation in research must be made an integral part of predoctoral medical education. Teaching and research have become complementary components of the educational process. Together with clinical experience, in- struction and research comprise the essential ingredients of modern education in the health sciences. It is therefore clear that academic depart- ments of radioZogzJ cannot perform their educa- tional function unless strong efforts are directed 17 TABLE III-Funds made available for research training by the Public Health Service, including the National Institutes of Health, during the fiscal year 1964 (13). Discipline Diagnostic Roentgenology -__----- Radiation Therapy ----- -__--_--- Nuclear Medicine ---- --___--___- Totals --- ______ r--------------- All Disciplines ------- ---_ - ---___ Predoctoral Training Grants $25,000 - - $25,000 $14,806,500 Postdoctoral Training Grants $315,739 857,485 195,145 $1,368,369 $151,101,372 Traineeships $220,000 129,500 - $351,500 $3,929,383 Total $562,739 986,985 195,145 $1,744,869 $169,837,255 toward the improvement of their research cap- in radiology can be raised to levels consistent ability. with the best of other medical school disciplines. In addition to the difficulties just cited, there is yet another problem which has reduced the number of teachers in radiology and hence has made the recruitment of physicians for the radiological sciences more troublesome. This problem comprises a complex series of economic relationships which together form a repeating chain of difficulties, each of which causes or exaggerates the next. The broadening demand for clinical service and the increasing shortage of trained physicians have combined to create economic forces which have placed sharp up- ward pressure on the professional fees of prac- ticing radiologists. Because the financial status of the academic radiologist must be tied more or less closely to that of his academic colleagues in other clinical disciplines, a serious economic gap has developed between the in- comes of academic and practicing radiologists which is diverting many a prospective academic radiologist to private practice. This problem is not likely to be resolved until manpower short- ages are alleviated. As plans are made to improve the depth and quality of academic radiology, it must be con- stantly borne in mind that medicine has under- gone enormous changes in the United States since the end of World War II. As the diagnosis and treatment of disease have become more complex, trends toward specialization have in- tensified. The radiological sciences have shared in this specialization. Increasing numbers of radiologists have found it necessary to restrict their work to such fields as cardiology, neur- ology or pediatrics. The need for further spe- cialization has arisen largely from the develop- ment of new and complicated roentgenological procedures which require extended periods of training and a penetrating knowledge of the subject material. (e) Current trends in academic radiology Although the picture of academic radiology in the United States is distressing, a few medi- cal schools have recently made substantial prog- ress in strengthening their departments of radi- ology. With the assistance of funds provided by the government and other sources, faculties have been increased and research facilities con- structed. Although a great deal still needs to be done, it is clear that with intensive effort, sup- ported with adequate funds, academic standards It has previously been pointed out that many of the radiological advances that have taken place in recent years have been developed by clinical investigators in disciplines outside of radiology. To some, this has seemed unfortun- ate. However, it has provided a superb oppor- tunity to infuse academic radiology with much- needed strength. Internists, pediatricians, and others whose research has taken them into radi- ological territory can do much to revitalize the specialty. To be completely effective, of course, these physicians must be accepted as full mem- bers of the radiological faculty. If such physi- cians are wisely assimilated, they will be of great assistance in transforming academic radi- ology into an attractive and stimulating disci- pline, well balanced in teaching, research and clinical service to patients. 18 The field of radiology in general and academic radiology in particular could also be markedly benefited if increasing numbers of radiologists were to play a larger role in the research, teach- ing and service functions of other medical disci- plines, thus developing a counterpart to the trend just cited. An effective research program in the radiological sciences requires a thorough understanding of the needs of the clinician. Such understanding in many cases can only be at- tained by day-to-day association with investiga- tors in other clinical disciplines, on the wards and in the experimental laboratories. In a field such as radiology, whose activities embrace almost every clinical discipline, it per- haps may seem unnece;l.::ary to speak of the need for strong interdiscipliziary ties. However, as academic radiology has found itself more and more restricted to the provision of clinical serv- ice to patients, it has become increasingly iso- lated. In the years ahead, it is incumbent upon every faculty member in the field to break through the barriers of isolation and to strengthen his associations with other clinical disciplines. To do otherwise will lengthen the time before academic radiology assumes its proper role in the health sciences. (f) Other manpower needs in the radiologi- cal sciences Although shortages in physician manpower are of great concern, they are not the only gaps in personnel prevailing in the radiological sciences. Similar gaps exist in: (1) non-physi- cian professional manpower, including radiolog- ical engineers, radiochemists, radiological phy- sicists, radiobiologists, and radiological health specialists ; (2) technical personnel, including clinical x-ray and nuclear laboratory technolo- gists ; and (3) other supporting personnel, in- cluding nurses and administrative staff. Radiological Engineers: Engineering has played a prominent part in the development of all of the radiological sciences. However, its importance is only now becoming fully recog- nized. The role of the radiological engineer is twofold: (1) to develop the broad range of radiological instruments, materials and appa- ratus needed by the health professions and (2) to supervise the technological operations of de- partments of radiology. The instrumentation needed by the radiological sciences has become so complex that highly skilled engineering talent is necessary not only for its design but also for its application in clinical practice. Hence, there has arisen a need for the radiolog- ical engineer to assume a direct clinical role in close association with the radiologist. Training programs needed for the develop- ment of radiological engineers currently do not exist. Hence, such programs should be initiated without delay. They must be highly specialized, providing not only experience in the physical sciences but in several of the biomedical disci- plines as well. The trainee must acquire compe- tence in such diverse fields as electronics, optics, information theory, mechanical engineering, computer technology and electricity and mag- netism; he must also take substantial amounts of work in such subjects as human anatomy and physiology. This background is essential if he is to design effectively the advanced instrumen- tation needed by the radiologist or if he is to achieve his greatest usefulness as a technolog- ical advisor to the clinical personnel with whom he is associated. The recent emergence of radiological engi- neering as an important scientific discipline has created a demand for radiological engineers that is difficult to fill. This manpower gap re- quires early correction if American medicine is to maintain a leading position in the radio- logical sciences. Hence, training programs for such engineers should be undertaken promptly. Radiochemists: Radiochemistry had its ori- gin in the 1930's. In the biomedical field, it grew out of the need for synthetic processes in which radioactive materials are incorporated into complex organic molecules for use either as radiopharmaceuticals or as components of biochemical systems in fundamental research. In the rapid advances which have taken place in nuclear medicine in recent years, the radio- chemist has played an important and perhaps even a dominant role. Indeed, progress in nu- clear medicine is highly dependent upon the ability of the radiochemist to provide a continu- ing series of useful radiopharmaceuticals. As with the radiological engineer, the train- ing requirements of the radiochemist are string- ent. Basic experience must be provided in the 19 disciplines of inorganic, organic and physical chemistry. Additionally, intensive training must be provided in biochemistry, pharma- cology and in the sophisticated techniques of complex organic synthesis. Because of the rapid growth of nuclear medi- cine and of the applications of labelled com- pounds in biological research, radiochemists are in short supply. Hence, in the opinion of those in the field, it is urgent that training pro- grams to develop these specialists be under- taken as soon as possible. The speed with which the products of atomic research can be trans- lated into medical benefits for the public is largely dependent upon the availability of such personnel. The growth of nuclear medicine therefore will be sharply curtailed unless the supply of radiochemists is substantially in- creased. Other No~Physicicun Specialists: In radio- biology and radiological physics (including health physics and nuclear engineering), the Atomic Energy Commission recognized several years ago the need for additional personnel in these fields and established a series of training programs to meet this demand. Also, the Di- vision of Radiological Health, Public Health Service, took steps to provide the manpower re- quired to maintain safe operating practices in the radiological sciences when it instituted in 1960 a program of training grants for radio- logical health specialists. These programs have been increasingly effective in supplying needed scientific personnel. Their success clearly indi- cates that serious effort should now be made to provide support for the training of all scientists needed in the radiological sciences. Technical Manpower: In the field of techno- logical manpower, serious difficulties currently prevail in the provision of adequate numbers of clinical x-ray and nuclear laboratory technol- ogists in the United States. Recently, at the President's White House Conference on Health, it was pointed out that members of the para- medical disciplines, including technologists, have been underpaid for many years. Conse- quently, the field of technology has been rel- atively unattractive to graduating high school students who are seeking vocational opportuni- ties. This is particularly true in the case of male students, even though many such students have much to offer the radiological sciences because of their inherent aptitudes. Furthermore, the long-term employment stability of such indi- viduals is highly desirable. The foregoing is not to say that the opportunities for female tech- nologists in the radiological sciences are limited. On the contrary, they are unusually bright. However, experientie has shown that the ma- jority of female technologists pursue their careers for only three to four years before leav- ing it for marriage. The fields of x-ray and nuclear technology are sufficiently stringent in their training require- ments that two years or more of training be- yond the high school diploma are necessary for an individual to become a competent tech- nologist. Such an educational background just- ifies a wage scale which is competitive with other vocations having similar standards. It is to be hoped that, in the years ahead, the lot of the chronically underpaid technologist may be improved. Without this change, it will become increasingly difficult to increase the effective- ness with which radiological services are de- livered to the public. The establishment of mini- mum legal standards of education, training and experience for such technologists appears to be necessary to bring this about. Because technological manpower is so impor- tant to all of the radiological sciences, the Committee believes that the Division of Radio- logical Health, Public Health Service, should undertake as soon as possible a broad study of the technological manpower requirements of the United States to determine the magnitude of current shortages and to recommend ways and means by which these shortages may be cor- rected. In making this study, the Service should seek the cooperation of all professional and tech- nological groups having an interest in this subject. Among these may be included the American College of Radiology, the American Society of Radiologic Technologists, the Health Physics Society and the Radiation Research So- ciety. (g) The correction of manpower shortages in the radiological sciences From the foregoing discussions, it is apparent that the correction of manpower shortages in the clinical divisions of the radiological sciences 20 is clearly linked to the strengthening of aca- demic departments of radiology in American medical schools. Radiological faculties must be strengthened and funds for research facilities must be made available as the development of academic radiology broadens and matures. Funds must also be made available for the training of additional radiologists, medical stu- dents, non-physician professional personnel and technologists. This Committee envisions the need for a broad series of training and research programs in the radiological sciences. These programs are required to upgrade the quality of the radiolog- ical services which have become such a critical part of medical and dental care and to improve radiation protection practices in the health pro- fessions. In the field of training, these programs may be divided into three principal categories: (1) a series of programs to strengthen radio- logical instruction of medical students and to increase the number of academic and practicing radiologists ; (2) a series of programs to in- crease the number of radiological engineers, radiological physicists, radiobiologists, radio- chemists and radiological health specialists ; and (3) a series of programs to provide quality training to increasing numbers of technologists (See table IV). TABLE IV-Training Programs Required in the Radiological Sciences I. Professional- (Physicians) Predoctoral Training-Institutional support Postdoctoral Training-Institutional and individ- ual traineeship support (i) clinical radiologists (ii) academic radiologists II. Professional- (Non-Physicians) Undergraduate Training-Institutional support Graduate Training-Institution and individual traineeship support (i) radiological engineers (ii) radiochemists (iii) radiological physicists (iv) radiobiologists (v) radiological health specialists III. Technological Undergraduate Training (i) x-ray technologists (ii) radiation therapy technologists (iii) nuclear medicine technologists Physician Truining : As in most clinical disciplines, the types of training programs needed for physicians are dependent upon the academic level for which they are intended. At the predoctoral level, funds are needed to strengthen the faculties of academic depart- ments of radiology. By this, the radiological background of all physicians can be improved and more students attracted to careers in radi- ology. Major effort must be made to communi- cate to the student the exciting professional opportunities available to him in a radiological career. At the postdoctoral level, two types of pro- grams are required: one to train substantial numbers of men who may be expected to enter the practice of radiology and one to train men who may be expected to follow academic ca- reers. Practicing Radiologists: In the past, the Pub- lic Health Service has provided only limited funds for the training of clinicians. However, a few years ago such support was introduced in the field of psychiatry and mental disease. At the time, this discipline .was suffering many of the problems currently facing the radiological sciences. Physician manpower was grossly in- adequate to meet the public's demand for psy- chiatric service. Psychologists, social workers and many other supporting personnel were in short supply. It was necessary to undertake bold new programs to meet the challenge which these problems presented. After long and care- ful thought, a residency training program for practitioners in psychiatry was undertaken. Its success is now well known. Not only have in- creased numbers of physicians been attracted to the specialty but their caliber has improved substantially as well. The success of this program suggests that it might well be adapted to increase the number of residents entering the field of radiology. In- deed, the Committee believes its initiation to be of the greatest urgency. In the early phases of the residency training program in psychiatry, funds were distributed mainly to educational institutions to strengthen teaching faculties and to provide such equip- 21 ment, supplies and facilities as were necessary to develop sound training programs. Approxi- mately one-third of the funds were made avail- able for resident stipends. In recent years, lesser amounts have been necessary for institu- tional purposes and, consequently, resident stipends have been increased in number and amount. Ultimately it is expected that approxi- mately three-quarters of the training funds will be used for this purpose. A similar history may be expected in radi- ology. After a long period in which educational responsibilities have not been met, institutional resources in radiology are small and require substantial augmentation. However, as time passes, increasing amounts of training funds can be diverted to residency stipends, thereby making it possible to close the gap between the demand for radiological service and the avail- ability of trained manpower. It is difficult to determine precisely the mag- nitude of the program needed for the training of additional radiological practitioners. A bal- ance must be made between the number of trainees required to substantially correct cur- rent manpower shortages within a reasonable period of time and the number of trainees who can actually be attracted to clinical radiology. Every effort should be made to increase the annual number of physicians entering the radi- ological sciences from the current level of 500 to a level of 800 or more; that is, to attract 300 additional trainees into the field each year. Even though this goal is high, the demand for addi- tional clinical radiologists is great and hence serious attempts should be made to reach it. At present, the accreditation of a radiologist by the American Board of Radiology requires that he complete three years of approved train- ing in the clinical disciplines of the radiological sciences plus an additional year of training or a year. of radiological practice. Therefore, the enrollment of 300 additional trainees each year will require the availability of 900 to 1,200 extra training positions. If quality training is to be furnished, these positions should be large- ly provided by an expansion of existing training facilities in the nation's large general and uni- versity hospitals. Such expansion shox be easily possible in most of the institutions with- out important dilution of the clinical material required for training purposes. Academic Radiologists: If programs to pro- vide adequate instruction in radiology to all physicians and to train increasing numbers of practicing radiologists are to be successful, it is essential that a sufficient number of teachers be made available in the clinical disciplines of the radiological sciences. However, as pointed out heretofore, serious shortages in academic manpower currently prevail in radiology. It therefore is clear that the development of train- ing programs for radiological teachers must be given the highest possible priority in health planning for the nation. Currently, there are approximately 800 full- time academic radiologists in the United States.@) To increase this number substantially over the next decade, it is estimated that 100 additional physicians must enter training in academic radiology each year. Moreover, 400 extra training positions must.be established in this nation's university hospitals if these men are to be given four years of training. The training to be furnished should include broad experience in the fundamentals of radi- ology. Opportunities should be provided for study in the related basic sciences as well as in the clinical disciplines of the radiological sci- ences. Also, the trainee early in his career should be given the freedom to pursue his studies without commitment to a particular field of radiological specialization and yet, later on, to have the opportunity to direct his attention to any one of a broad range of special interests. By the development of a comprehensive, well- balanced series of training programs in aca- demic radiology, manpower deficiencies are likely to be corrected in the shortest possible time. In recent years, modest sums for radiological research training have been made available in a number of special fields by several of the insti- tutes of the Public Health Service. Among these are the National Cancer Institute for training in radiation therapy; the National Heart Institute for training in cardiovascular radiology; and the National Institute of Neuro- logical Diseases and Blindness for training in neuroradiology. These disease-related training 22 programs, although limited in scope, have been quite worthwhile. They should be continued, unchanged in administration, as important ad- juncts to the comprehensive training programs proposed in this report. In addition to the training programs just cited, the National Institute of General Medical Sciences, with guidance from several advisory groups including this Committee, has recently established a series of programs to provide support for research training in diagnostic roentgenology and nuclear medicine. Although limited in funds, these programs are a partial step in meeting the demand for increased num- bers of academic radiologists. Non-Physician, Professional Training : One of the most important needs prevailing in the radiological sciences is training support for the development of such non-physician pro- fessional personnel as radiological engineers, radiological physicists, radiobiologists, radio- chemists and radiological health specialists. Some years ago, the Public Health Service, as a part of its training programs in radiation ther- apy and cancer control, established support for radiobiologist training. Also, an excellent train- ing program for radiological health specialists has been operated for several years by the Service's Division of Radiological Health. How- ever, specific support for the other types of non- physician specialist training has been either in- adequate or lacking. Certainly, the importance of these personnel is sufficiently great that such deficiencies must be corrected. Unless they are, medical progress in the radiological sciences, in- cluding efforts to improve equipment and prac- tices from the point of view of radiation protec- tion, will be markedly hampered and American radiologists will become increasingly dependent on the scientists of other countries for the technological advances needed for the develop- ment of their profession. As in training programs for radiologists, the size of the effort to train professional personnel in the supporting disciplines of the radiological sciences may be dictated more by the avail- ability of trainees than by the need for such personnel. It is noteworthy, however, that in spite of the recruitment problems which have occurred in many of the science-related gradu- ate training programs supported by U.S. Government, the universities and colleges as- sociated with the Division of Radiological Health in its training program for radiological health specialists have had, in the main, excel- lent success in filling student quotas. In view of this, every effort should be made to initiate training programs which will provide as early as possible increasing numbers of such non- physician professional personnel as radiochem- i&s, radiobiologists, radiological physicists as well as radiological engineers. These programs must of course provide the trainee with support sufficient to carry him through three or four years of training to a master's or doctoral degree. From the experience of the Division of Radiological Health, it appears that 100 or more trainees in these disciplines may be recruited each year without difficulty. Technologist Training: The need for training of technological per- sonnel has been noted heretofore (see table IV). However, the Committee wishes to make no recommendations concerning the character and scope of this training pending the completion of the studies on technological manpower now being undertaken by the Division of Radiologi- cal Health. Research Grants : The need for research funds in the radiologi- cal sciences perhaps requires little discussion. Over the past two decades, such grants have become such an integral part of the American academic scene that their importance is well recognized. However, the Committee wishes to call attention to the need for applied research and development projects to increase the effec- tiveness and safety of radiological procedures in the health professions. Grants for Training and Research and De- velopment Facilities: The paucity of support for radiological train- ing, research and development to which refer- ence has been repeatedly made in this report has caused a marked deficit in research and training facilities both at the clinical and lab- oratory levels in most academic departments of radiology. For this reason, a program of con- 23 struction grants specifically for radiological research and training must be established to correct this deficiency. Indeed, the effective- ness of the training and research grant pro- grams outlined in preceding paragraphs will be limited unless this program is undertaken. It is difficult to overemphasize the facilities deficit which has been allowed to develop in academic departments of radiology. Without question, it is substantially greater than that experienced by any other major discipline. Un- fortunately, its correction will be costly. The characteristics of the radiological sciences are such that their requirements in both space and equipment are unusually expensive. It is per- haps for this reason that corrective measures heretofore have been so inadequate. However, a deficit of this magnitude cannot be allowed to continue in a discipline which, each day, through its dominant role in the provision of TABLE V-Estimated `Annual Costs of Additional Training and Research Support Needed in the Radiological Sciences I. Training Grants : Predoctoral Training Grants (Physician) Institutional Support ----$ l,OOO,OOO Postdoctoral Training Grants (Physician) Radiological Practitioners: Stipends for 1,200 trainees ------------$ 7,200,OOO Institutional support ---$ 2,400,OOO Academic Radiologists : Stipends for 400 trainees ------------$ 4,000,OOO Institutional support ---$ 2,000,OOO Graduate Training Grants (Non-Physician) Stipends for 400 trainees ------------$ 1,876,OOO Institutional support ---$ 625,000 $19,100,000 II. Research and Facilities Grants Research Grants- Additional Support ------$10,000,000 Research and Training Facilities _______ --------$10,000,000 $20,000,000 $39,100,000 quality health care to the public, affects as many people as the radiological sciences do. The estimated cost of the new training and research programs outlined in preceding para- graphs is shown in table V. In the case of the training programs, the data were derived from the number of individuals to be trained each year of the several programs and from infor- mation on stipends and related institutional requirements derived from the experience of the Public Health Service. Recommendations for added funds for research are perhaps mod- est. However, the proposed amount of $lO,- 000,000 per year is intended principally to pro- vide research support leading to improvements in the effectiveness and safety of radiological procedures. As for other research support, the Committee hopes that, as academic radiology is strengthened, it may be able to attract an increasing share of grant support from exist- ing sources. The amounts of money recom- mended for training and research facilities in the radiological sciences are based on the ex- pectation that, over the next ten years, most and perhaps all of the 100 medical schools which are expected to be in operation by 1975 will require on the average upward of $l,OOO,- 000 each. These requirements are high. How- ever, as previously pointed out, the needs are unusually great. . V. PHS Program Development in the Radiological Sciences (a) The need for a un@ed administratim Preceding sections of this report have dis- cussed the developing role of the Public Health Service in the radiological sciences. A number of its current activities have been outlined and some of the important unmet needs have been pointed out. Discussions have also centered on some of the programs which the Public Health Service should undertake to resolve the radio- logical problems now confronting the nation. In the development of these programs, it is necessary to understand that the radiological- sciences comprise a complex series of inter- dependent disciplines, no one of which stands apart; the problems which affect one have a strong influence on the others. Hence, these 24 problems are not suitable for solution by a series of uncoordinated efforts. It is not enough to alleviate the problems of diagnostic roent- genology or nuclear medicine without attack- ing the difficulties prevailing in radiological health, radio-chemistry or radiological engi- neering ; and it is not enough to support radio- logical health or radiation therapy without giving support to radiobiology or radiological physics. In brief, program development in the radiological sciences requires a unified effort. The uses and control of ionizing radiation in the health professions perhaps constitute the most striking example of the interdependence of the several disciplines comprising the radio- logical sciences. Advances in diagnostic roent- genology, radiation therapy and nuclear medi- cine are providing an ever-expanding series of benefits to mankind in the diagnosis and treat- ment of disease. Yet as valuable as these bene- fits may be, they are accompanied by increas- ing risks as exposures to ionizing radiation be- come greater. Hence, continuous attention must be given to the balance of benefit and risk whenever public health activities relating to the medical applications of ionizing radiation are undertaken. This demands the closest pos- sible relationship between those concerned with developments in clinical radiology and those working in radiological health. Because of these considerations, the Service should avoid fragmentation of its radiological activities. Programs supporting academic ra- diology should not be isolated from those per- taining to the control of ionizing radiation ; and activities related to the training of professional personnel should not be disassociated from those concerned with the training of technol- ogists. Although sometimes administratively desirable, such fragmentation inevitably leads to serious inconsistencies in program devel- opment. In urging a unified effort in the radiological sciences, the Committee does not wish to imply that there should be no activities relating to these sciences in other divisions and institutes of the Public Health Service. On the contrary, the manner in which the radiological sciences are often involved with other scientific disci- plines in the study of biomedical problems re- quires the development of a number of radio- logical activities in other agencies. Examples of such activities include the training program in neuroradiology supported by the National In- stitute of Neurological Diseases and Blindness and the training program in cardiovascular radiology supported by the National Heart In- stitute. (b) Strengthening of laboratory and stati- tical services As part of its comprehensive effort in the radiological sciences, the Service should de- velop two important resources: (1) a well- equipped and superbly staffed radiological lab- oratory to provide expert technical assistance to the health professions and to federal, state and local agencies concerned with the applica- tions and control of ionizing radiation and (2) a well-supported statistical service to collect and analyze a broad range of data useful in the identification and evaluation of radiolog- ical problems. Excellent laboratory resources are a neces- sary component of the Service's effort to im- prove the effectiveness with which radiological methods are applied in the health professions, to reduce occupational and environmental ex- posure from ionizing radiation and to acceler- ate the rate at which the benefits of the ra.- diological sciences are made available to the public. In the development of these resources, the Service should follow the pattern of its Communicable Disease Center where, in the field of microbiology, laboratory services have been effectively integrated and developed to a high level of excellence. If similar laboratory resources are established for the radiological sciences, the nation will be much closer to a solution to many of its problems arising from the applications and control of ionizing radi- ation. The development of substantial statistical resources in the radiological sciences will IX1 a longstanding need. Many of the radiological problems confronting the nation today may be ascribed to the absence of such resources in the past. For example, current manpower shortages would almost certainly have been detected at a much earlier time if data call- 26 ing attention to the unusual growth in clin- ical demand for radiological services had been available. Among the broad range of radio- logical data which should be under contin- uous collection and analysis are : (1) appropri- ate exposure data to identify those radiological installations where radiation control efforts have fallen short of accepted standards; (2) exposure data on selected groups of people to provide information valuable in the epidemio- logical study of the relationships between radi- ation dose and biological effects; (3) data on the availability of professional and technical manpower in the radiological sciences ; (4) data providing a measure of the growth in de- mand for radiological services in the health professions; and (5) data which may be used to determine the effectiveness with which pub- lic health programs in the radiological sciences are meeting their goals. The systematic col- lection of these and other data requires resources available only in a major govern- ment-supported facility. These resources should be given a high priority in radiological pro- gram development. RESTATEMENT OF RECOMMENDATIONS In this report the National Advisory Com- mittee on Radiation has made a number of recommendations which it hopes may be help- ful to the Surgeon General in meeting the re- sponsibilities of the Public Health Service in the radiological sciences. For convenience, these recommendations are summarized as fol- lows : 1. The Public Health Service should take im- mediate steps to strengthen its programs in the radiological sciences by unifying their administrative direction. Such action is needed to assure an orderly development of the broad spectrum of radiological activities for which the Service is responsible and to give contin- uous attention to the balance of benefit and risk in all matters pertaining to the human application of ionizing radiation. 2. The Service should undertake the follow- ing training and research and development programs to upgrade the quality of the radio- logical services which have become such a crit- ical part of medical and dental care and to improve radiation protection practices in the health professions : (a) a series of training programs : (i) to strengthen radiological instruction of medi- cal students; (ii) to increase the number of academic radiologists in American medical schools; and (iii) to increase the number of practicing radiologists in the United States. (b) a series of training programs to pro- vide increasing numbers of radiochemists, radiological engineers, radiobiologists, radi- ological physicists and radiological health specialists. (c) a series of training programs to pro- vide increasing numbers of technologists in the several disciplines of the radiological sciences. (d) a series of applied research and devel`- opment programs to increase the effective- ness and safety with which radiological pro- cedures are employed in the- health profes- sions. (e) a series of programs to provide train- ing and research facilities for academic de- partments of radiology in American medi- cal schools. 3. The Service should take the initiative in the formulation and promulgation of (a) stand- ards dealing with the qualifications of person- nel who operate the x-ray equipment or who use radioactive materials not regulated by the Atomic Energy Commission ; (b) design stand- ards for sources containing radium and other radioactive materials that are not reactor by- products ; and (c) standards for the premar- keting clearance of x-ray equipment used in the health professions and in industry. 4. The Service should take appropriate ac- tion to assure that official health agencies play an increasing prominent role in the appraisal of the health risks associated with the construc- tion and operation of major nuclear facilities. 5. The Service should take immediate steps to strengthen its laboratory and statistical re- sources in the radiological sciences. These rs sources are essential components of the PHS 26 effort to meet the Surgeon General's responsi- bilities to the nation. 6. If needed, appropriate legislative author- ity should be sought at the earliest possible time to carry out the foregoing recommenda- tions. BIBLIOGRAPHY 1. The Control of Radiation Hazards in the United States. A Report to the Surgeon General by the Nat. Adv. Comm. on Rad., Dept. of Health, Educ. and Welf., Pub. Health Service, March 1969. 2. 3. 4. 6. 6. 73 Stat. 688. Atomic Energy Act of 1964, as amended. Radioactive Contamination of the Environment: Public Health Action. A Report to the Surgeon General by the Nat. Adv. Comm. on Rad., Dept. of Health, Educ. and Welf., Pub. Health Service, May, 1962. Public Law 89-9'7, Social Security Amendments of 1966. Report No. 680, to accompany H.R. 10686. (Depts. of Labor and Health, Educ. and Welf. Supple- mental Appropriation Bill, 1966) 89th Congress, 1st Session. Congressional Record, Sept. 3, 1966. Health Statistics: Volume of X-ray Visits, United States, July 1960June 1961. Series B, No. 38. U.S. Dept. of Health, Educ. and Welf., Pub. Health Service, 1962. 7. Cancer Rates and Risks. PHS Publication No. 1148, U.S. Dept. of Health, Educ. & Welf., Pub. Health Service, 1964. 8. Radioisotopes in Medicine. Stanford Research In- stitute. Prepared for Oflice of lsowycs ~~v&ynlent, U.S. Atomic Energy Commission. Washington, D.C., 1969. 9. From data supplied by Dept. of Circulation and Records, Am. Med. Assoc., Chicago, Ill. 10. Comm. on Rad. Has and Epid. of Malform., Am. Acad. Ped. Pediatrics, 28:676,1961. 11. Medical Education in the United States, Staff of the Council on Medical Education. J.A.M.A. 190 :626, 1964. 12. Coggeshall, L. T. Planning for Medical Progress through Education. A Report Submitted to the Exe- cutive Council, Assoc. of Am. Med. COB. Evanston, 1966. 13. Public Health Service Grants and Awards, Fiscal Year 1964 Funds, Part II, Training Grants, Trainee- ships, Fellowships and Research Career Program Awards. PHS Publication No. 1233, Part II. U.S. Dept. of Health, Educ. & Welf., Pub. Health Serv- ice, 1964. 14. Public Health Service Grants and Awards, Fiscal Year 1964 funds, Part I-Research tirants, rHS Publication No. 1233, Part I. U.S. Dept. of Health, Educ. & Welf., Pub. Health Service, 1964. 0 U.S. GOVERNMENT PRINTING OFFICF: 1966-O 218-937 27