N C H S - National Survey of Ambulatory Surgery

	National Hospital Discharge and Ambulatory Surgery Data
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The National Survey of Ambulatory Surgery (NSAS) is the only national study of ambulatory surgical care in hospital-based and freestanding ambulatory surgery centers (ASCs). The NSAS was first conducted from 1994 to 1996, but it was discontinued due to lack of resources. The NSAS is being conducted again in 2006.

Data for the NSAS will be collected for approximately 60,000 ambulatory surgery cases from a nationally representative sample of hospital-based and freestanding ambulatory surgery centers.

These data have and will be used for a variety of planning, administrative and evaluation activities by government, professional, scientific, academic, and commercial institutions, as well as by private citizens.

Who is eligible to participate?
The basic study population for the NSAS is patients scheduled for surgical and nonsurgical procedures performed in hospital-based and freestanding ambulatory surgery centers. The hospital universe includes non-Federal general, short-stay and children’s hospitals located in the 50 states and the District of Columbia. The universe of freestanding ambulatory surgery centers includes facilities which are state licensed or Medicare certified or which provide ambulatory surgery as the primary business activity and operate independently as a separate business.

Why participate?
NSAS participation is important because without it, neither your facility nor others like yours can benefit from being represented in the national description of surgical visits to hospital-based and freestanding ambulatory surgery centers. Your facility was randomly chosen to provide representative data not only for its own ambulatory surgical visits, but also for similar facilities in the same geographic region.

What are the benefits of participating?
By participating in the NSAS, you will be able to contribute to the national description of ambulatory surgical care in the United States. Data from the National Survey of Ambulatory Surgery has and will provide the only nationally representative source of clinical information on ambulatory surgery. It will complement data obtained through the National Hospital Discharge Survey, as well as expand the coverage of the National Health Care Survey.

Data from the National Hospital Discharge Survey have been extensively used for four decades in monitoring changes and analyzing the types of surgical treatment provided to hospital inpatients. However, due to advances in medical technology, surgical treatment and diagnostic procedures are increasingly provided in settings which are outside the scope of the NHDS. The growth of freestanding ambulatory surgery facilities and ambulatory surgery programs in hospitals has been rapid, and the decline of these procedures on an inpatient basis has been documented by the NHDS.

Your facility’s participation in the NSAS will result in more reliable statistics and will enable researchers to better measure the utilization and provision of ambulatory surgical care. Failure to participate lessens the accuracy of the data used by researchers.

After nearly ten years of being out of the field, the NSAS data collection instruments were updated to reflect the changing environment in ambulatory surgery. Outside experts from the American College of Surgeons, American Association for the Accreditation of Ambulatory Surgery Facilities (AAAASF), American Association of Ambulatory Surgery Centers (AAASC), the American Academy of Ophthalmology (AAO), the American Hospital Association (AHA), the Society for Ambulatory Anesthesiologists (SAMBA), the Federation of American Hospitals (FAH), the Joint Commission of Accreditation of Healthcare Organizations (JCAHO), the Federated Ambulatory Surgery Association (FASA), and the American College of Obstetrics and Gynecology (ACOG) provided input into updating the data collection tools used for NSAS.

Many of the new questions being asked in the 2006 NSAS are about the facility in which the ambulatory surgery is being conducted. Each sampled facility will be asked to complete a Facility Questionnaire and return it in the mail.

Confidentiality of NSAS data
The NSAS is conducted under the authority of Section 306 of the Public Health Service Act (42 USC 242k), which requires NCHS to collect statistics on a variety of health indicators. Information collected in this survey is used to study overall patterns of health care use by the population and for other similar statistical purposes. NCHS has a long history of protecting the privacy of information that we collect, and Section 308(d) of the Public Health Service Act (42 USC 242m) assures the confidentiality of data collected in the NSAS. We strictly observe this confidentiality statute, which prohibits the release of identifiable information that we obtain unless we are given consent to do so by the subject.

HIPAA Privacy Rule and NSAS
This section contains an overview of the Privacy Rule and how it affects your NSAS participation. For more comprehensive information on the Privacy Rule and the NSAS, please go to HIPAA Privacy Rule Q’s and A’s for NSAS.
The final Privacy Rule has been published as required by the Health Insurance Portability and Accountability Act of 1996 (HIPAA). Health care providers who transmit financial and administrative health information electronically must comply with the Rule as of April 14, 2003.

The Privacy Rule permits your facility to make disclosures of protected health information without patient authorization for public health purposes or for research that has been approved by an Institutional Review Board (IRB). This survey meets both of these criteria. Additionally, disclosures may be made under a data use agreement with NCHS. If you have questions about your facility’s rights as a respondent, you may call the IRB at 1-800-223-8118. The IRB is an independent board that protects the interests of people who take part in studies. Click here to see the IRB approval letter and IRB continuation approval letter for NSAS.

We have included all the information you need to be assured that your facility is allowed to disclose protected health information for the NSAS in our introductory letter to facilities and also here on our website. However, there are several things that you must do to assure compliance with the Rule when participating in the survey. First, the privacy notice that your facility generally provides to patients must indicate that patient information may be disclosed for either research or public health purposes. And, secondly, your facility may need to keep a record of the disclosure (which we will provide) that shows that some data from the patient’s medical record were disclosed to CDC for the NSAS. Of course, if your facility does not transmit health information electronically (such as claims data), then it is not subject to the Privacy Rule or the requirements described above.

The Privacy Rule applies to data collected for the NSAS because we are asking you to provide certain information about patients without their authorization. For public health and research purposes, the NSAS collects information from the patient's medical record such as surgical visit date, birth date, and residential ZIP code. While not directly identifiable, these data are considered protected health information as defined by the Privacy Rule. As described above, the Rule allows you to disclose this information for public health and research purposes.

Please be assured that we fully intend to continue our long history of gaining the voluntary participation of facilities like yours by upholding the highest confidentiality standards and practices.

For additional information on the confidentiality of NSAS data, please go to NCHS's Privacy Protection page.

Your assurance of privacy
NCHS is legally bound to assure confidentiality of all responses, including any information that might result in a hospital or ambulatory surgery center being identified. The data files that are released for research do not include any provider or patient identifying information.

The NSAS does not collect any personally identifiable data about patients such as patient's name or address. Sample visits are randomly selected using the surgery schedules that the facility has as a part of its routine recordkeeping requirements. The medical records that are included in the sample are identified and listed on the Sample Listing Sheet. The Sample Listing Sheet is a four part form on NCR (no carbon required) paper and the top sheet, which contains medical record numbers and possibly other identifying information, is retained by the facility to assure confidentiality. The top copy is kept by facility staff for several months, in case it is necessary to retrieve missing information or clarify recorded information.

Other information that may permit identification of an individual, or a facility will be held confidential, will be used only by persons engaged in and for the purpose of the survey, and will not be disclosed or released to other persons or used for any other purpose without consent of the individual or the establishment in accordance with section 308(d) of the Public Health Service Act (42 USC 242m).

A copy of the NSAS Medical Abstract form can be found on this page under the section, Survey Instruments.

How are NSAS data used?
NSAS data are used to provide statistics that describe the characteristics of ambulatory surgical visits to hospital-based and freestanding ambulatory surgery centers. These include patient demographic characteristics; source of payment; information on anesthesia given; the diagnoses; and the surgical and non-surgical procedures of patients visiting hospital-based and freestanding ambulatory surgery centers.
These data are used by the U.S. Congress and other public health policy makers, government agencies, universities and medical schools, professional associations, health services researchers and epidemiologists, as well as the print and broadcast media, to describe and understand the changes that occur in medical care. The data are disseminated in the form of public health reports, journal articles, and microdata files. To see a list of selected articles using the NSAS and NHDS, click here.

How are NSAS data released?
Data for the 2006 NSAS will be released several ways. Summary data from the 2006 NSAS will be available in reports from the National Center for Health Statistics. In addition, reports that combine data on ambulatory surgery and surgery performed on hospital inpatients during 2006 will also be published. Reports on topics of special interest may also be published. Information will also be published in journal articles and in papers presented at professional meetings. As resources permit, special tabulations and analyses will be provided to both public and private data requestors. To view published reports on the 1994-1996 NSAS, click here.

In addition to published reports on NSAS, a public-use micro data file and supporting documentation will be prepared for distribution at professional society meetings, health data conferences, and through the NCHS website. NSAS data will also available on CD-ROM. Identification of facilities and patients cannot be made from the public-use data files.

Annual public use files containing information collected by the NSAS were made available for the 1994-1996 NSAS and will be made available for the 2006 NSAS. To facilitate trend analyses, multi-year public use files of NSAS data in a standard format with standard definitions across survey years was and will be made available. CD-ROMs for 1994-1996 in ASCII format are currently available to the public, and 2006 NSAS data will also be available in this format.

"I can’t think of a more important way for an ASC professional to spend [their] time. In the face of increasing legislative and regulatory challenges to our industry, our ability to produce the kind of data this survey is collecting is growing. When you participate in surveys such as this one, you help the whole ASC industry as well as your own ASC." -- Jack Egnatinsky, MD, President, Federated Ambulatory Surgery Association (FASA)

To read the article on NSAS that appeared in the January/February 2006 issue of FASA Update, click here.

If you have any further questions or comments related to participation, please contact Karen Cullen at: