National Institute on Drug Abuse
Director's Report to the National Advisory Council on Drug Abuse
February, 1999
Research Findings
AIDS Research
Increased Transmission of Vertical Hepatitis C Virus (HCV) Infection to Human Immunodeficiency Virus (HIV) Infected Infants of HIV and HCV Co-infected Women
The transmission of perinatal HCV infection was studied retrospectively in infants born to HCV and HIV co-infected women enrolled in a prospective natural history study of HIV transmission. Infant HCV infection was assessed by RNA PCR. The overall rate of vertical HCV transmission was 16.4% (9/62). The rate of HCV infection was higher among HIV-infected infants than among HIV-uninfected infants (40% vs.5%; OR, 8.2; p=.009). This difference in transmission was not related to maternal HCV viral load by branched DNA assay, or mode of delivery. The rate of HCV transmission in HIV-uninfected infants of HIV and HCV co-infected mothers was similar to that reported for infants born to HIV-uninfected mothers. Papaevangelou, V., Pollack, H., Rochford, G., Kokka, R., Hou, Z., Chernoff, D., Hanna, Krazinski, K., Borkowsky, W. J Infect Dis., 178, pp.1047-52, 1998.
Sex Differences in HIV-1 Viral Load and Progression to AIDS
A study of HIV-1 viral load differences in men and women was performed in an ongoing cohort study of injection drug users. Women were found to have significantly lower viral load measurements than men. HIV-1 was measured by branched chain DNA at baseline, and by reverse-transcriptase PCR and quantitative microculture on follow-up three years later. Median viral load measurements were significantly lower in women than men by all three methods. Viral load measurements in women were 38- 65% of those in men. The association of lower viral load in women remained even after adjusting for CD4 cell count, race, and drug use. While men and women had statistically similar time to AIDS, women with the same viral load as men had a 1.6-fold higher risk of AIDS, or, equivalently, women with half the viral load of men had a similar time to AIDS. These results suggest that, while men and women have similar time to AIDS, there is a different relationship between viral load and AIDS in women compared to men. While a biological mechanism remains to be elucidated, these findings have implications for timing of initiation of therapy relative to viral load thresholds in women. Farzadegan, H., Hoover, D., Astemborski, J., Lyles, C.M., Margolick, J.B., Markham, R.B., Quinn, T.C. Lancet, 352, pp.1510-1514, 1998.
Gp120 May Facilitate the Entrance of HIV into Body Compartments
Gp120, an envelope protein found in HIV, may facilitate the entrance of HIV-infected monocytes into body compartments by enhancing immunocyte-endothelium interactions that favor transmembrane migration. Long-term or continuous exposure of the endothelia to morphine and anandamide resulted in a significant enhancement of monocyte adherence and this appeared to be due to desensitization of endothelium to further NO release. Whereas gp120 did not stimulate the release of constitutive endothelial NO, morphine and anandamide elicited the release of NO. Collectively, these findings suggest that the continued presence of abused substances may result in more rapid progression to AIDS probably due to a higher viral load in individuals that abuse these substances and have HIV. Stefano, G.B., Salzet, M., Bilfinger, T.V. Journal of Cardiovascular Pharmacology, 31, pp. 862-868, 1998.
Comprehensive Treatment for HIV Positive Cocaine and Opioid Dependent Patients: Preliminary Findings
Drs. Avants, Margolin, DePhilippis, and Kosten from Yale University in Connecticut have recently reported on a preliminary study in which 6 HIV positive opioid and cocaine dependent patients were provided a 12 week comprehensive pharmacological and psychosocial treatment program designed to address the treatment needs of HIV positive drug users. This program included buprenorphine (12mg/day), buproprion (150 mg/day), and twice weekly manual-guided group therapy. Preliminary findings showed decreases in IV cocaine use, cocaine craving, and depressive symptoms compared to outcomes of the patients receiving the standard methadone maintenance treatment. Journal of Substance Abuse Treatment, 18(3), pp. 257-258, 1998.
Assessment of HIV Risk
Dr. Chawarski and colleagues at Yale University propose a number of solutions aimed at improving validity and efficiency of assessment of HIV risk in drug abusing populations. Five domains of assessment are discussed; intravenous drug use, high-risk sexual behaviors, knowledge of HIV transmission and methods of prevention, psychological aspects of behavioral change, and epidemiological factors of HIV transmission. The paper also discusses format, scope and context, as well as scoring procedures that may improve discriminability and sensitivity to detect change over the Risk for AIDS Behavior (RAB), one of the most commonly used instruments to assess risk behavior. Finally the AIDS Risk Inventory (ARI), a risk assessment instrument which incorporates methodological improvements discussed in the paper, is described. Chawarski, M.C., Pakes, J., Schottenfeld, R.S. Journal of Addict Dis., 17, pp. 49-59, 1998.
Perinatal Transmission of Hepatitis C Virus from HIV-1 Infected Mothers
Antepartum plasma hepatitis C virus (HCV) RNA was quantified in 155 mothers enrolled in the Women & Infants Transmission Study (WITS) who were co-infected with HCV and HIV, and HCV RNA was serially assessed in their infants. Of 155 infants born to HCV-antibody positive mothers, 13 (8.4%) were HCV infected. The risk of HCV infection was 3.2-fold greater in HIV-infected infants compared with HIV-uninfected infants (17% vs. 5.4%, p=0.04). The median concentration of plasma HCV RNA was higher among the 13 mothers with HCV-infected infants (2.0 x 10(6) copies/mL) vs. 142 mothers with HCV-negative infants (3.5x 10(5) copies/mL; p<0.001). There were no instances of HCV transmission from 40 mothers with HCV RNA concentrations of <10(5) copies/mL. The results indicated that HIV-infected infants have a higher risk of HCV infection than HIV-uninfected infants, but that women dually infected with HIV-1 and HCV with little or no detectable HCV RNA have a low risk of transmitting HCV to their infants. Thomas, D.L., Villano, S.A., Riester, K.A., Hershow, R., Mofenson, L., Landesman, S.H., Hollinger, F.B., Davenny, K., Riley, L., Diaz, C., Tang, H.B., and Quinn, T. J. Infect Dis.,177, pp. 1480-1488, 1998.
Declining HIV Seroprevalence in New York City Suggests A New Phase of the Epidemic
Researchers assessed recent trends in HIV seroprevalence among IDUs in New York City by analyzing temporal trends from 1991 to 1996 in 5 studies of IDUs recruited from a detoxification program, a methadone maintenance program, and research storefronts in the Lower East Side and Harlem areas, and a citywide network of STD clinics. A total of 11,334 serum samples were tested. From 1991 through 1996, HIV seroprevalence declined substantially among subjects in all 5 studies: from 53% to 36% in the detoxification program, from 45% to 29% in the methadone program, from 44% to 22% at the Lower East Side storefront, from 48% to 21% at the Harlem storefront, and from 30% to 21% in the STD clinics (all p<.002 by chi square tests for trends). The duration of the epidemic, the available death rate data, and the declining seroprevalence among long-term injectors all indicate loss of HIV-seropositive persons as a contributing factor to the decline in HIV seroprevalence among IDUs in New York City. In addition, continuing risk reduction, recent HIV incidence studies, and declines in HIV among new injectors indicate risk reduction or low HIV incidence as another contributing factor. These reductions in HIV seroprevalence among IDUs in New York City indicate a positive, new phase in the very large epidemic. HIV prevention efforts should be continued to maintain these favorable trends. Des Jarlais, D.C., Perlis, T., Friedman, S.R., Deren, S., et al. Declining Seroprevalence in a Very Large HIV Epidemic: Injecting Drug Users in New York City, 1991 to 1996. Am. J. Public Health, 88(12), pp.1801-1806, 1998.
HIV Risks are Associated with Multiperson Use of Injection Equipment in IDU Networks
This paper examines serial use of drug injection equipment and paraphernalia, using concepts and methods from ethnographic research in combination with social network theory to help understand the behavioral transactions that link IDUs in the drug acquisition, preparation, and injection process. Seven of the sites in the NIDA Cooperative Agreement (CA) for AIDS Community-Based Outreach and Intervention Research program conducted an ethnographic substudy of injection episodes among out-of-treatment IDUs to examine drug acquisition and multiperson use of paraphernalia, drugs, and needles/syringes. Ethnographers observed 54 injection episodes in which IDUs were linked by HIV risk behaviors, and developed a typology of higher-risk, lower-risk, and nonsharing-risk networks. Multiperson use of injection paraphernalia or drug solution occurred in most injection events (94%). Serial use of syringes/needles occurred infrequently (14%) relative to "backloading" (37%) and reuse of paraphernalia (cookers 84%, cottons 77%, water 77%). Higher risk injection networks were characterized by larger size and pooling of resources for drugs. Study findings suggest several public health recommendations. Specifically, in addition to emphasizing use of sterile syringes/needles, HIV prevention efforts should focus attention to the more subtle and elusive behaviors involved in multiperson use of drug preparation and injection paraphernalia that are used to transfer drug solutions among injectors. At a minimum, this information should be a standard part of all prevention messages for IDUs, combined and incorporated into existing prevention strategies, including outreach, drug user treatment, HIV antibody testing and counseling, and syringe exchange programs. Needle, R.H., Coyle, S., Cesari, H., Trotter, R., et al. HIV Risk Behaviors Associated with the Injection Process: Multiperson Use of Drug Injection Equipment and Paraphernalia in Injection Drug User Networks. Substance Use and Misuse, 33(12), pp. 2403-2423, 1998.
Noninjecting Drug Users More Likely to Change Drug Use than Sexual Risk Behaviors
Researchers analyzed data from five of the study sites in the NIDA Cooperative Agreement (CA) for AIDS Community-Based Outreach and Intervention Research program to determine how the outcomes of noninjecting drug users differed after receiving either the standard or the enhanced intervention. In this analysis, change in behavior was stratified into two categories based on a matrix of levels of risk: improved or worsened conditions. Three key variables were analyzed: change in crack/cocaine use, change in the number of sexual partners, and change in the frequency of condom use. There were 1,434 noninjecting crack/cocaine users in the sample, classified according to their self-reports of never having injected drugs or of at least not injecting in the 12 months before the interview. Of these, 82% improved crack/ cocaine use at the follow up. The enhanced intervention group showed more improvement in crack/cocaine use than the standard intervention group. Overall, 76% reported reducing sexual partners, maintaining a one-partner relationship, or abstaining from sex at both time periods. Women in the enhanced intervention group improved more than women in the standard intervention (81% vs 75%). In terms of condom use, more respondents worsened than improved (55% vs 45%). This study confirms that HIV/AIDS interventions can reduce crack/cocaine use; however, high-risk sexual behaviors are more difficult to change. Reasons for this lack of improvement and suggestions for future interventions are discussed. Cottler, L.B., Leukefeld, C., Hoffman, J., Desmond, D., Wechsberg, W., et al. Effectiveness of HIV Risk Reduction Initiatives among Out-of-Treatment Noninjection Drug Users. J. Psychoactive Drugs, 30(3), pp. 279-290, 1998.
Psychosocial Risk and Protective Factors for Condom Use Among Female Injection Drug Users
This study was designed to examine the influences of domains of psychosocial risk and protective factors on male-partner condom use in a cohort of 209 female HIV-positive (HIV+) and HIV-negative (HIV-) injection drug users (IDUs) by use of a cross-sectional, retrospective design. Information was collected from a structured questionnaire and included data on psychosocial risk and protective factors in the personality, family, and peer domains; HIV status; and condom use. Among HIV+ IDUs, personality risk factors (e.g., unconvention-ality), family (e.g., low maternal identification), and peer factors were related to less male-partner condom use. Resources and condom availability were associated with greater male condom use with both HIV+ and HIV- IDUs. These findings suggest the need to use specific psychosocial interventions to prevent risky sexual behavior among HIV+ and HIV- female IDUs. Brook, D.W., Brook, J.S., Whiteman, M., Gordon-Maloul, C., Win, P.T., Masci, J.R., Roberto, J., de Catalogne, J., and Amundsen, F. Psychosocial Risk and Protective Factors for Condom Use among Female Injection Drug Users. American Journal on Addictions, 7, pp. 115-127, 1998.
HIV Risk among Latinas
This study examined the psychosocial risk factors for HIV infection in a community sample of Latinas. National data indicate that women of various Latin and South-American nationalities (including Latinas of Mexican decent) are nearly three times more likely to acquire AIDS than other women in the United States. Structural equation models were used to test relationships among predictors, mediators (including components of the Health Belief Model), and sex-related outcomes and behavior in a random, cross-sectional community sample of 227 sexually-active Latinas (M-age = 32). Acculturation was significantly associated with higher HIV- related risks in their primary relationships. Older Latinas were less likely to make behavior changes or use barrier methods of contraception to prevent HIV and had higher rates of unintended pregnancies compared to younger Latinas. Marriage was related to greater risk in relationship and less behavior change. Theoretical models accounting for ethnicity, race, and culture are needed to understand better unwanted sexual outcomes for Latinas, including HIV risks. The need for strategies that specifically address these issues for HIV prevention and counseling programs for Latinas is discussed. Newcomb, M.D., Wyatt, G.E., Romero, G.J., Tucker, M.B., Wayment, H.A., Vargas, J. H., Solis, B., & Mitchell-Kernan, C. Acculturation, Sexual Risk Taking, and HIV Health Promotion Among Latinas. Journal of Counseling Psychology, 45, pp. 454-467, 1998.
HIV Risk among African-American Youth
Ramirez-Valles and colleagues examined the community and personal risk factors for HIV infection among a predominantly African-American sample of teenagers at risk for drug abuse. Sexual activity among high-school-aged youths has steadily increased since the 1970s, emerging as a significant public health concern. Yet, patterns of youth sexual risk behavior are shaped by social class, race, and gender. Based on sociological theories of financial deprivation and collective socialization, the authors developed and tested a model of the relationships among neighborhood poverty; family structure and social class position; parental involvement; prosocial activities; race; and gender as they predict youth sexual risk behavior. Structural equation modeling was used to test this model on a cross-sectional sample of 370 sexually active high-school students from a midwestern city; 57 percent (n = 209) are males and 86 percent are African American. Family structure was found to indirectly predict sexual risk behavior through neighborhood poverty, parental involvement, and prosocial activities. In addition, family class position indirectly predicts sexual risk behavior through neighborhood poverty and prosocial activities. Ramirez-Valles, J., Zimmerman, M.A., and Newcomb, M.D. Sexual Risk Behavior among Youth: Modeling the Influence of Prosocial Activities and Socioeconomic Factors. Journal of Health & Social Behavior, 3, pp. 237-253, 1998.
Factors Identified in HIV Sex Risk Behavior Change among Puerto Rican Drug Users
Researchers studied change in sex risk behaviors and factors related to change among 911 IDUs and 359 crack smokers recruited from the San Juan metropolitan area. A total of 1,004 (79.1%) of the drug users at baseline were assessed at follow-up. Abstinence from sex behavior increased from 54.6% to 61.1%, use of condoms during vaginal sex also increased from 26.4% to 36.9%. In multivariate analysis, significant predictors of abstinence were gender, injection drug use, HIV seropositivity, and not having a steady partner. Predictors of using condoms during vaginal sex were HIV seropositivity, STD diagnosis and participation in an HIV prevention program. These findings indicate that additional HIV prevention efforts are needed to reduce sex risk behaviors among drug users who have a steady sex partner as well as among drug users who are HIV negative. Robles, R.R., Marrero, C.A., Matos, T.D., Colon, H.M., et al. Factors Associated with Changes in Sex Behavior among Drug Users in Puerto Rico. AIDS Care, 10(3), pp. 329-338, 1998.
Racial Comparisons of HIV Risk Found to Have Little Utility in Rio de Janeiro, Brazil
Racial identities in Brazil are dynamic concepts which can only be understood if situated and explored within appropriate cultural contexts. The fluidity of racial identification in Brazil became empirically evident in this study, conducted in the context of a prevention initiative targeting segments of the Rio de Janeiro population at high risk for HIV/AIDS. Comparisons of client data at baseline and follow-up assessments form the analytic core of the research program, since its main objective is to slow the spread of AIDS through an intervention designed to promote behavioral change. Using quality control procedures to link client information collected at different points in time, researchers found that 106 clients (i.e., 12.5% of the 849 clients in the follow-up sample) had changed their racial identification. Specifically, 5.7% changed from black to white, 30.2% from black to brown, 20.8% from white to brown, 3.8% from white to black, 23.6% from brown to black, and 15.1% from brown to white. Analyses of the shifts in racial self-identification suggest that interviewer characteristics were an important influence on a client's self-reported race. One of the strongest predictors of a change in racial identity was having a different interviewer at baseline and follow-up. Those assigned a black interviewer at follow-up were less likely to change their race than those interviewed by a white, but clients interviewed by different white interviewers at baseline and follow-up were most likely to change race. Interestingly, members of all racial categories were equally likely to shift their identification at the second contact, so that racial identity at baseline was not predictive of race changing at follow-up. In the U.S., race continues to be one of the most significant and consistent predictors of HIV risk and serostatus. By contrast, in Brazil, race was found to have very little utility for predicting HIV risk, sexual activity, drug use, and behavioral changes. Surratt, H.L. and Inciardi, J.A. Unraveling the Concept of Race in Brazil: Issues for the Rio de Janeiro Cooperative Agreement Site. J. Psychoactive Drugs, 30(3), pp. 255-260, 1998.
Geographic Information Systems Used to Assess Spatial Patterns of Drug Use
Researchers in Baltimore explored the use of Geographic Information Systems (GIS) to study whether frequency and type of drug use are geographically located within the city of Baltimore independent of neighborhood characteristics. They also sought to assess geographic factors associated with sample selection attrition. GIS is typically used to capture, store, manipulate, display, and analyze geographically referenced data, so that the spatial relations among variables can be assessed, such as those among census tracts, transportation routes, block-level crime, and household residences. For this study, 597 out-of-treatment IDUs, who were part of an ongoing project, AIDS Linked to Intravenous Experiences (ALIVE), made up the study sample, in addition to those with whom they shared drugs. The participants had been recruited into an HIV intervention program called Stop AIDS for Everyone (SAFE), the clinic for which was located three blocks from the ALIVE clinic. Drug users who resided further from the clinic reported more sharing of syringes, and in the western section of the city, a greater proportion of IDUs reported daily cocaine use and any use of crack cocaine. Even after adjusting for individual level and census tract data on demographic characteristics, geographic residential location continued to be associated with drug use. The results of this study suggest that type and frequency of drug use is associated with specific geographic areas, independent of neighborhood characteristics. These results have implications for the location of drug use interventions, needle exchange, and other HIV prevention activities. Latkin, C., Glass, G.E., and Duncan, T. Using Geographic Information Systems to Assess Spatial Patterns of Drug Use, Selection Bias and Attrition among a Sample of Injection Drug Users. Drug and Alcohol Dependence, 50, pp. 167-175, 1998.
Study Finds that Shooting Gallery Managers are at Great Risk of Communicable Diseases
Researchers in Puerto Rico assessed HIV risk behaviors, HIV seroprevalence, and tuberculosis infection in 464 IDUs, 12.5% of whom managed shooting galleries. The median frequency of drug injection was higher in shooting gallery managers than in nonmanagers. A trend was observed for purified protein derivative reactivity to increase according to the length of time spent as a gallery manager, but it was not statistically significant. However, anergy rates increased significantly with increases in the number of months spent as shooting gallery manager. Multivariate analyses showed that IDUs reporting shooting gallery management experience of >25 months were more likely to be infected with HIV. Prevention programs need to emphasize strategies to protect the health of shooting gallery clients and, in particular, shooting gallery managers. Additional studies are required to determine effective strategies for reducing the risk of HIV and TB infection in shooting galleries. Robles, R.R., Marrero, C. A., Reyes, J.C., Colon, H.M., et al. Risk Behaviors, HIV Seropositivity, and Tuberculosis Infection in Injecting Drug Users Who Operate Shooting Galleries in Puerto Rico. JAIDS, 17(5), pp. 477-483, 1998.
HIV Prevention Protocols Adapt to Evolving Changes in Substance Abuse Environments
Applied research in HIV prevention with out-of-treatment drug users occurs in an environment that is constantly changing. As a consequence, it is necessary for researchers to identify changes in drug use and sexual risk patterns, develop and evaluate appropriate interventions to respond to those changes, and find ways to make effective use of new technologies as they are developed. An example of this is the collaborative revision of NIDA's Standard Intervention for HIV prevention by the six final study sites in the NIDA Cooperative Agreement (CA) for AIDS Community-Based Outreach and Intervention Research program. In this paper, researchers from these six sites review the history of the National AIDS Demonstration Research (NADR) and CA programs and recent changes made to the Standard Intervention protocol. The review illustrates the processes and rationale involved when responding to changes in the substance abuse environment and adapting HIV prevention protocols to those changes. Wechsberg, W.M., Desmond, D., Inciardi, J.A., Leukefeld, C.G., et al. HIV Prevention Protocols: Adaptation to Evolving Trends in Drug Use. J. Psychoactive Drugs, 30(3), pp. 291-298, 1998.
Multisite Study Finds Acceptability of the Female Condom by High Risk Women
In 1996, six study sites participating in the NIDA Cooperative Agreement (CA) for AIDS Community-Based Outreach and Intervention Research program initiated a collaborative project to examine the acceptability of the female condom among women at high risk for HIV infection. Specifically, they sought to introduce the female condom to a large sample of women drug users, to explore its acceptability as a risk-reduction device among these women, and to examine correlates of its use. In this paper, individual site data are presented from three of the participating sites, San Antonio (115 women), St. Louis (106 women), and Rio de Janeiro (97 women). The women represented a diversity of background characteristics at each of the three sites, with a median age of 28 in Rio de Janeiro, and one of 36 in St. Louis. More women were single in both Rio and St. Louis, but more were married or cohabiting in San Antonio. Most of the women in the study in St. Louis were African American, and most were Latina in San Antonio and multiracial in Rio. The findings from this study are presented as preliminary and representative of women in just three of the six sites. Nonetheless, they signify one of the largest cohorts of high-risk, drug-involved women studied to date in terms of their experiences with the female condom. While use rates varied widely by site, use was related most closely to frequency of sex, the number of sex partners, trading sex for drugs, and male condom use. In San Antonio, women who engaged in high-risk sex for drug exchanges were almost 3 times more likely to try the female condom than were nontraders. In Rio, female condom use was much more likely among users of the male condom, suggesting that substitution of female condom use for male condom use may have occurred among those who were dissatisfied or had partners who were unhappy with some aspect of the male condom. Finally, women at 2 of the 3 sites favored the female condom over the male condom and rated it higher on the basis of overall satisfaction. The authors conclude that, as an innovative device that was unfamiliar to almost all the women in the study, the female condom was favorably received. The fact that large proportions of the women at each site used the female condom on more than one occasion also suggests that those who had a positive first-use experience were willing to continue using it as a method of risk reduction. Surratt, H.L., Wechsberg, W.M., Cottler, L.B., Leukefeld, C.G., et al. Acceptability of the Female Condom Among Women at Risk for HIV Infection. American Behavioral Scientist, 41(8), pp. 1157-1170, 1998.
Stages of Adaptation and Negotiating Behavioral Change in HIV+ Adolescent Girls
A demonstrative case of an HIV-positive girl is presented in order to illustrate the stages of adaptation that HIV positive youth undergo (i.e., acceptance, resumption of life, coping with reminders of serostatus). Also discussed is the process by which this individual changes her behavior (e.g., reduction in transmission behaviors, adherence to medical programs, improving quality of life) and the integral role and contributions the service provider can make in the behavioral-change process for HIV-positive youth. Finally, this case illustrates some of the unique issues encountered by HIV-positive women and how those issues can be incorporated into a comprehensive, coordinated, and continuous system of care through an intervention such as Teen Linked through Care (TLC). Lightfoot, M. and Rotheram-Borus, M.J. Negotiating Behavior Change with HIV-Positive Adolescent Girls. AIDS Patient Care, 12(5), pp. 395-401, 1998.
Prevention of Substance and Sexual Risk-Taking in Hispanic Women
The concepts of risk and resilience, which are at the heart of health promotion and risk prevention are discussed, and used to demonstrate the acceptability of these concepts in the development and pilot testing of a primary prevention intervention to reduce substance abuse and risky sexual behaviors among low-income, predominantly Mexican-American women. Six important findings emerged from this pilot study: 1) Motivation and readiness are key to recruitment and consistent participation; 2) The quality of the content and materials and the use of participatory learning principles and teaching methods are key to effective teaching and learning; 3) The importance of a trusting and caring environment is essential; 4) The intervention must be tailored to life's realities and must address felt needs; 5) Risky behavioral decisions are often not taken rationally or consciously; 6) Cultural and family norms play a significant role in decision-making. Lindenberg, C.S., et al., Resilience and Risk: Preventing Substance Abuse and Sexual Risky Behaviors Among Low-Income Minority Young Women. Maternal Child Nursing, 23(2), pp. 99-104, 1998.
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