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Summary More than 115,000 persons in the United States have been diagnosed with acquired immune deficiency syndrome, or AIDS, since the illness was first identified in this country almost 10 years~ago. As we enter the second decade of the epidemic, residual problems from the first decade continue to compel the nation's attention. Moreover, new issues are emerging that call for immediate consideration and action. The dimensions of the epidemic are sizable and will continue to grow, presenting enormous challenges to the nation and to those individuals who must track its course, design and implement intervention programs, and provide medical care and other services. This report reviews the course of the epidemic and its current status. It also discusses prevention activities designed to curb the future spread of the human immunodeficiency virus (HIV) and offers recommendations regarding potential avenues for achieving this goal. This report was prepared by the Committee on AIDS Research and the Behavioral, Social, and Statistical Sciences, which was established in 1987. The formation of such a committee within the National Re- search Council reflected a growing awareness that understanding HIV transmission, facilitating behavioral change to prevent further spread of infection, and coping with the social consequences of the epidemic raise questions that properly lie within the domain of the social, behavioral, and statistical sciences. At the request of the Public Health Service (PHS) and with support from the Russell Sage and Rockefeller Foundations, the committee reviewed estimates of the extent of HIV infection in the U.S. ~ This work builds on the past and ongoing work of the Institute of Medicine (IOM)/Naiional Academy of Sciences (NAS). The IONVNAS has produced two major reports that focused on public health, bio- logical research, and medical care issues: Confronting AIDS: Directions for Public Health, Health Care, and Research (1986) and Confronting AIDS: Update 1988 (both published by the National Academy Press, Washington, D.C.).

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2 ~ AIDS: THE SECOND DECADE population and the patterns of sexual behavior and drug use that trans- mit HIV. It also reviewed intervention strategies that showed promise of producing behavioral change to slow the spread of HIV infection in the general population. In 1989 the committee issued its first report, AIDS, Sexual Behavior, and Intravenous Drug Use.2 The committee's studies dunng this most recent phase of its efforts have considered the evolving shape of the epidemic, focusing attention on populations and research topics that will be of increasing importance in coming years. After discussions with liaison representatives of the PHS, the committee accepted the following as its charge: to review the changing nature of the epidemic in the United States and the needs of the diverse populations being affected by it, such as adolescents and women (including female prostitutes); to descnbe behavioral research and intervention strategies that could assist in protecting the blood supply; and to review a selected set of methodological issues that affect the quality of data collected in surveys of drug use and sexual practices. This volume is the committee's response to its charge. In preparing it, the committee was assisted by a specially appointed Panel on AIDS Interventions and Research.3 In continuing to monitor the progression of the epidemic and the nation's response, the committee notes several important changes in this evolving and enduring health problem. New populations that are at risk are emerging from populations that heretofore have not been touched directly by AIDS and from subgroups of populations that are already known to bear infection. Moreover, shifts in patterns of risk-associated behaviors are now becoming apparent. For example, although the threat of disease transmission posed by intravenous (IV) Mug use has been recognized since the early years of the epidemic, there is now a growing appreciation of the indirect hazards (e.g., sexual risk taking in the context of drug use) posed by drugs that are not injected, such as the form of cocaine known as crack. There is also increasing awareness of the need to maintain risk-reducing behaviors once they have been initiated. The persistence of risk in the environment and the problem of relapse mandate a long-term commitment to prevention. 2 turner' C. F., Miller, H. G. and Moses, L. E (1989) AIDS, Sexual Behavior, and Intravenous Drug Use. Report of the National Research Council Committee on AIDS Research and the Behavioral, Social, and Statistical Sciences. Washington, D.C.: National Academy Press. 3 The committee also benefited from the work of a second panel, which reviewed methodologies for evaluating the effectiveness of AIDS prevention programs. The panel's report, Evaluating AIDS Pre- vention Programs, Expanded Edition (S. L. Coyle, R. F. Boruch, and C. F. Turner), will be published in mid-1990 by the National Academy Press.

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SUMMARY ~ 3 In the second decade of the epidemic, new pockets of infection are being identified in more diverse geographical locations in the United States, and the changing distributions of AIDS cases and HIV infection indicate that the disease is becoming more a generalized American phe- nomenon and less a bicoastal, urban entity. Moreover, the pattern of infection is also beginning to reveal some subtle shifts in the distribution of AIDS cases across transmission categories; the proportion of cases attributable to same-gender contact has decreased slightly as the propor- tion ascribed to heterosexual contact has grown. Even the characteristics of the disease itself are somewhat in flux. With the development of drugs capable of decreasing morbidity associated with HIV infection and prolonging the lives of those infected with the virus, the disease takes on some of the characteristics of a long-tenn rather than an acute illness. The changing locus of the epidemic, the new populations at risk, and the emerging longer term nature of the disease point to the need for new outreach and intervention strategies to prevent further spread of infection, as well as services and treatment to assist those who are already infected. The first two sections of this summary (and Chapters 1 and 2 of the full report) describe the evolving nature of the epidemic and the range of prevention activities that are being implemented to retard the spread of HIV in the U.S. population. A particular focus of these sections is the increasing burden of HIV infection and AIDS among women. The next three sections (Chapters 3, 4, and 5, respectively, of the full report) review three domains of particular interest: the ways in which HIV infection is affecting adolescents and female prostitutes, and the challenge of protecting the blood supply while simultaneously ensuring the adequacy of that supply. The final section of the report (Chapter 6) reviews factors that affect the quality of data collected in surveys of AIDS-related behaviors. Although many of the specific issues raised in this report are persist- ing problems from the first decade of the epidemic, it is important to note that some predicted problems have not emerged. For example, despite considerable speculation regarding the role prostitution could play in a self-sustaining heterosexual epidemic, the data presented in Chapter 4 do not support the notion that HIV infection is an occupational disease of sex workers. Rather, the infection found among female prostitutes appears to have been acquired through IV drug use or from sexual con- tact with a husband or boyfriend, and, in several surveys, substantial proportions of prostitutes reported condom use with paying customers. Moreover, in a field where there have been few real successes, the story of the blood supply stands out. The development of HIV antibody tests,

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4 ~ AIDS: THE SECOND DECADE which when coupled with behavioral interventions to enhance appropriate blood donor deferral, has dramatically reduced the number of infections associated with the blood supply. However, as donor deferral becomes more effective, there will be fewer individuals to contribute to the blood supply, thus raising additional problems concerning adequate supplies. The committee cautions that encouraging results and promising situa- tions should not lead to complacency. The lessons learned from the first decade of the epidemic warn us of the need for vigilance as the patterns of disease shift and new problems emerge. THE CHANGING EPIDEMIOLOGY OF AIDS IN THE UNITED STATES Despite the greater diversity now recognized to exist among at-nsk and infected populations, gay men still account for the majority of AIDS cases in this country. Yet more and more cases are reportedly associated with IV drug use and heterosexual transmission, and this shift has resulted in a noticeable increase in the number of women who are affected by the AIDS epidemic. Among adolescents in contact with the military (either as applicants or on active duty), rates of HIV infection among females are comparable with those for males. Gender panty in seroprevalence (i.e., prevalence of HIV infection) for this population indicates that for some groups women will be bearing a larger share of the AIDS burden in the future. Although the majority of female AIDS cases have been attributed to IV drug use, substantial numbers of infected women report heterosexual contact with an infected male IV drug user. Thus, injection of illicit sub- stances poses direct and indirect threats to women in this country. The stabilization of infection rates seen among drug users in some cities (e.g., New York, San Francisco, Amsterdam) affords some hope that inter- ventions directed toward this population can be effective.4 Nevertheless, stable rates of infection in selected cities do not signify the elimination Of viral transmission. Other areas of the United States, as well as for- eign countnes, are seeing rapid increases in the incidence of infection among IV drug users. The mobility of this population coupled with the 4For some groups at highest risk for HIV infection, stable rates signify that all vulnerable individuals are already infected, a phenomenon known as saturation. This phenomenon does not appear to explain stable rates in New York City, however, where approximately 50 percent of IV drug users are esti- mated to be infected. If saturation had occurred, one would expect to see higher seroprevalence rates. For example, approximately 90 percent of IV drug users in New York City have been infected with hepatitis, a virus that is transmitted in the same manner as HIV and appears to have reached saturation in this population.

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SUMMARY | 5 persistence of the behaviors that transmit HIV (namely, sharing injection equipment) indicates that the potential for very rapid spread still exists. Furthermore, growing awareness of the indirect threat posed by drugs such as crack and alcohol supports the notion that HIV risk related to drug use now goes beyond the use of contaminated injection equipment. Although crack and alcohol do not directly transmit HIV, researchers note that both Mugs are associated with high-nsk sexual practices and thus confer an indirect risk for the acquisition and transmission of the virus. The rapid emergence of new, drug-related threats highlights the need for vigilance regarding changing patterns of transmission. Thus, the committee recommends that the Public Health Service establish mechanisms across its agencies for rapid identification and assess- ment of the relationship of new drug use problems to the spread of HIV. At present it is clear that crack use and its associated unsafe sexual activity represent a potentially important new mode of HIV trans- mission in the United States, but it is unclear how large an impact this mode might have. The committee recommends that the Public Health Service support additional research on crack use, including its epi- demiology, its relationship to sexual behavior, strategies to reduce its occurrence (both initiation of use and continuance among low- and high-frequency users), and methods for facilitating change in the sexual behavior of persons who continue to use crack. Among the changing facets and aspects of the epidemic, one epidemi- ological trend has remained disturbingly constant. Black and Hispanic men and women continue to be overrepresented in every AIDS risk cate- gory. The committee urges a renewed commitment to providing effective AIDS prevention programs for at-nsk minority individuals. Therefore, the committee recommends that the agencies of the Public Health Service encourage and strengthen behavioral science research aimed at understanding the transmission of HIV in various black and His- panic subpopulations, including men who have sex with men, drug users and their sexual partners, and youth. The committee further recommends that the PHS ~levelop plans for appropriate interven- tions targeted toward these groups and support the implementation of intervention strategies (together with appropriate evaluation com- portents) in both demonstration projects and larger scale efforts. The evolutionary, dynamic nature of this epidemic imposes additional demands on surveillance data collection. High-quality data on changing rates of risk-associated behavior and HIV infection are needed to track the course of the epidemic and to evaluate the effectiveness of intervention efforts to stop its progression. To facilitate the Centers for Disease

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6 ~ AIDS: THE SECOND DECADE Control's (CDC) ongoing efforts to improve its AIDS-related data collection systems, the committee recommends that the agency initiate a systematic review of current programs. This effort should draw on the expertise of both CDC staff and outside experts. PREVENTION: THE CONTINUING CHALLENGE The first decade of the AIDS epidemic in this country brought consid- erable progress in solving the biological and epidemiological puzzles of AIDS and HIV infection. The causative agent was discovered, and serologic tests to detect infection were devised, produced, and imple- mented. In addition, drugs were developed to treat both the underlying viral infection and the opportunistic infections that are the hallmarks of the disease. Yet despite this progress, the epidemiological data reveal a steady progression of HIV-related morbidity and mortality, in part be- cause the development of HIV prevention strategies has not kept pace with He growing dimensions of risk. Effective intervention strategies are needed to sustain healthy behavioral patterns in individuals who are not currently at risk and to facilitate change among individuals who are. The committee finds that ongoing efforts fall far short of the magnitude of in- tervention needed, given the current prevalence of infection and evidence of continued nsk-associated behavior among many of the groups at risk for AIDS. AIDS Prevention Challenges in the Coming Decade At the beginning of the epidemic, interventions to prevent the spread of HIV infection focused pr~manly on adult gay men; subsequent prevention efforts encompassed the population of IV Hug users. Today, that focus requires redefinition and expansion once again as changing epidemio- logical patterns reveal greater diversity among at-risk groups. A further requirement is to consolidate study findings from cohorts of gay men and to incorporate relevant findings into the design and development of prevention activities for other groups. Unfortunately, an understanding of such lessons has been hampered by a host of methodological com- plications that preclude meaningful cross-study comparisons. Therefore, the committee recommends that the Public Health Service assemble and summarize data reported by gay men in PHS-funded studies re- garding seroprevalence, seroconversion, and high-risk behavior and determine what conclusions can be drawn from the research. Of particular concern to the committee are the epidemiological data indicating that HIV infection is spreading to disparate subpopulations of women. The diversity of the at-nsk female population mandates the

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SUMMARY ~ 7 development of multiple approaches to prevent both horizontal transmis- sion from sexual and Hug use partners and vertical transmission from a mother to her infant. In general, the best way to prevent vertical transmission is to prevent infection in women of childbearing age. Prevention efforts focused on women during the first decade of the epidemic relied heavily on testing and counseling, but several studies have shown that the information provided to women by such a strat- egy did not necessarily prevent transmission. Therefore, the committee recommends careful review of the goals of testing and counseling programs for women of childbearing age and the implementation of research efforts to ascertain the effect of such programs on fu- ture risk-taking behavior. Additional, innovative strategies are clearly needed to prevent vertical transmission; there may be important lessons to be learned from existing programs that have sought to prevent other vertically transmitted diseases, such as genetic disorders. The committee recommends that the Public Health Service convene a symposium of experts in genetic counseling to consider the potential contribution of this field's expertise and experience to the design and implementa- tion of counseling programs for HIV-infected women and to identify research opportunities in this area. In its first report, the committee recommended that knowledge con- cerning the efficacy of intervention programs be built in a systematic fashion through the use of planned variations of key program elements accompanied by rigorous evaluation. This process is admittedly quite time-consuming, but unfortunately there is no shortcut to the accumu- lation of such cntical information. Behavioral interventions are still the only available means of disease containment, and the committee an- ticipates that the need for well-designed, carefully implemented, and thoughtfully evaluated intervention efforts will not decrease over the course of the next 10 years. Therefore, the committee reiterates its earlier recommendations and in addition recommends the following: that the Public Health Service encourage and support behavioral research programs that study the behaviors that transmit HIV infection and that the PHS develop and evaluate mechanisms for facilitating and sustaining change in those behaviors; that intervention programs incorporate planned varia- tions that can be carefully evaluated to determine their relative effectiveness; that the PHS regularly summarize the data derived from currently funded behavioral and epidemiological

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8 ~ AIDS: THE SECOND DECADE research on AIDS (in terms of incidence of infection arid high-risk behaviors) to determine intervention priorities for various subpopulations at risk; and that all agencies of the PHS that are currently funding intervention programs and evaluation research regularly summarize the data derived from these studies to deter- mine which, if any, programs can be recommended for wider dissemination. There is some indication that AIDS prevention activities to date have, at least In part, achieved their goal; significant risk reduction has been reported among subsets of gay adult mates and IV drug users. Yet segments of every at-r~sk group continue to practice unsafe behaviors. Some have not yet initiated change; others have not been able to sustain changes initiated earlier. The committee recommends that the Alcohol, Drug Abuse, and Mental Health Administration focus research ef- forts on AIDS-related relapse prevention, including the determinants of such relapse and the role that alcohol and other drugs play in the return to unsafe sexual and injection practices. The inconsistent use of condoms is a common theme that cuts across all populations associated with this epidemic. Gay men, IV drug users, and female sexual partners of infected or at-risk individuals have all reported problems in initiating or maintaining condom use, despite clear evidence of perceived risk. In its first report the committee urged widespread availability and promotion of the use of condoms (with sper- micides) as a means for preventing sexually transmitted HIV infection. The epidemiological data show, however, that sexual transmission of the virus continues to be a major route of infection, and self-reported data on risk taking indicate that more research is needed to understand how to help people take preventive action against sexually transmitted HIV infection. The committee recommends that the Public Health Service fund research on condoms to achieve the following objectives: understand the determinants of condom use for the di- verse populations at risk for sexually transmitted HIV infection; improve condom design and materials to make them more acceptable to users; and develop interventions to promote their consistent use. Regardless of belief in the efficacy of condoms to prevent HIV transmission, not all subpopulations at risk will be able to implement this means of protection. Women in particular often find condom use

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SUMMARY ~ 9 problematic. Not only do condoms require the cooperation of the male partner but they may also require substantial changes in the attitudes and behaviors of some women. The gravity of the AIDS epidemic calls for other methods of protection that are more "user friendly" (i.e., more attractive, easier to purchase, and easier to use) and that can be uni- laterally employed by women. The committee recommends that the Public Health Service support research to develop protective mea- sures other than condoms for preventing HIV transmission during sexual contact~pecifically, methods that can be used unilaterally by women and methods that will be acceptable to both men and women who do not currently use condoms. The partnership between technol- ogy and the behavioral sciences has succeeded in devising mechanisms to protect the blood supply (see Chapter 5 of the report). Similar partner- ships are needed to develop innovative means for protecting individuals from sexual transmission of the disease. Impediments to Improved Intervention AIDS prevention programs must identify, contact, and help at-r~sk indi- viduals to assess their level of risk and access appropriate services. Pro- viding AIDS prevention also involves first facilitating and then sustaining behavioral change. Delivering programs to at-nsk individuals becomes extremely difficult if people believe that seeking help may threaten their jobs, housing, and supportive relationships. During the first decade of this epidemic, effective interventions and research were compromised by difficulties in identifying and reaching those most in need. Now, it is even more crucial to reach infected individuals because there are poten- tially beneficial prophylactic treatments that may forestall the progression of disease. Antidiscr~mination legislation has been proposed by several organizations to provide the institutional underpinnings necessary to en- able individuals to redress inequities and protect those who would seek care and other AIDS-related services. The committee is gratified to see that the federal antidiscnmination measures urged In its first report and recommended by the President's Commission on the HIV Epidemic are under active consideration. It would point out, however, that this legisla- tion alone is unlikely to ameliorate all of the conditions associated with discrimination in this country. For example, legislation may protect the rights of HIV-infected children to education but cannot prevent hostile encounters with the community. A separate pane] of the committee is currently considering methods to monitor and measure the social impact of the epidemic; the panel's report is expected to be released in 1991.

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10 AIDS: THE SECOND DECADE The progress made in instituting antidiscnmination provisions, how- ever, cannot obscure the fact that other hurdles remain in the path of improved intervention. The financial biers to health care that have im- peded preventive care for other health conditions also affect individuals seeking AIDS-related services. BaITiers to these services may be espe- cially daunting for women, in particular women who need prenatal care or treatment for Hug use. Moreover, even delivenng information to those most in need is sometimes problematic, in part because societal attitudes continue to hinder the implementation and evaluation of promising inter- ventions. A significant controversy has surrounded the appropriate level of sexual explicitness in AIDS prevention information and the degree to which these interventions should emphasize the erotic. Political debate abounds regarding the propriety of using public monies to support the development of sexually explicit matenals, despite preliminary evidence that, for some populations, they have a degree of effectiveness. Programs to provide IV drug users with stenie needles have also been stymied. Previous reports on AIDS from the National Academy of Sciences and the Prostitute of Medicine recommended that the U.S. government sponsor research on syringe exchange programs as a means of reducing the spread of HIV infection in the drug-using population. Evaluation of ongoing efforts abroad have found that participation in syringe exchange programs is associated with the reduction but not the elimination of behaviors that can transmit HIV and that syringe exchanges do not lead to any detectable increase in illicit drug injection, either among current users or by new injectors. The U.S. Department of Health and Human Services has considered the types of research that would be needed to evaluate the impact of syringe exchange programs on the spread of HIV, but it has not officially determined whether it will support such research now or in the future. There is a general! fear expressed by many policy makers that explicit messages concerning stenie injection equipment and condom use will result in increased rates of {V drug use and sexual intercourse. Yet what evidence there is from venous intervention programs suggests otherwise: having the information and the means to protect oneself from a deadly disease is likely to result in protective action against AIDS, as well as in generalized increases in healthy behaviors (e.g., seeking drug treatment) among people who are already engaging in risky activities. Furthermore, inflation and services do not appear to entice the uninitiated into risk-associated actions. The committee believes that the time has come to commit sufficient resources to the task of collecting data that would permit an assessment of whether current intervention strategies, including

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SUMMARY ~ 1 1 needle exchange programs, effectively decrease risky behaviors and the subsequent spread of HIV. To continue to rely on hunches and suspicions rather than on data gives too much credence to guesswork and may arbitrarily obstruct a promising course of action for preventing the spread of the epidemic. ADOLESCENTS The committee finds no credible evidence that He AIDS epidemic will cease in the foreseeable future in this country. As a result, prevention efforts remain cntically important. In terms of the adolescent population, the committee believes that intervention efforts will be most effective if the programs reach teens before they begin practicing the behaviors that put them at risk. Because patterns of both health behavior and risk taking are often established during the teenage years, intervention efforts for adolescents offer the hope of protecting our youth and preventing future problems in the adult population. It is important to note that not all teens are equally at risk for HIV infection. Some, by virtue of their low level of risky behavior or because of the absence of the virus among their potential partners, will remain uninfected. However, the available data on HIV seroprevalence indicate Hat there are presently localized pockets of the teen population In which the rates of infection are relatively high. Findings from CDC's neonatal surveillance activity (i.e., anonymous antibody testing of newborn in- fants)5 indicate, for example, that almost ~ percent of black teenagers who delivered children in New York City during 1988 were infected with HIV. The prevalence of HIV infection among Hispanic teenage mowers is almost as high. Data from serosurveys of nonprobability samples of hospital patients and data on infection rates among applicants for military service confirm the fact that the REV virus is seeded In the adolescent population, albeit at varying rates. Yet these sources of information are limited; consequently, there is a paucity of appropriate data available to scientists for monitoring He spread of HIV in He teen population. To provide better information about HIV infection and AIDS among adolescents, the committee recommends that the Centers for Disease Control make available to the research community AIDS-related data that permit separate consideration of teenagers and other age groups. Specifically, the committee recommends that: SThis testing provides unbiased estimates of the prevalence of HIV infection among childbearing women because infants circulate maternal antibody during the first months of life whether or not they are actually infected.

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SUMMARY ~ 27 Audits of blood use and educational programs that go beyond dissemina- tion of pamphlets and the traditional didactic method appear to hold the most promise; however, more data are needed to specify the character- istics of programs that are likely to be effective in modifying prescrib- ing patterns of physicians. The committee recommends that agencies of the Public Health Service sponsor the development, systematic testing, and implementation of transfusion-related intervention and education programs to facilitate change in physicians' attitudes and behaviors with regard to: encouraging healthy patients to donate blood; encouraging autologous donation where medically ap- propriate; eliminating the unnecessary use of blood and blood com- ponents; and employing appropriate procedures (e.g., perioperative blood salvage, use of erythropoietin) that reduce the need for transfusion. Standards or criteria regarding the appropriate use of blood and blood components are currently lacking, making it difficult to determine with certainty whether transfusions are being given appropriately. As a result, the committee recommends that the Public Health Service sponsor research to monitor trends in transfusion practices nationally to per- mit evaluation of the appropriateness of blood and blood component utilization and to identify targets for change. It further recommends that the PHS develop and evaluate effective strategies for informing patients about the risks and benefits of transfusion. SURVEY METHODS IN AIDS RESEARCH Surveys or, more generally, the method of asking questions and record- ing answers from a sample of a population of interest continue to be one of the most important techniques for obtaining essential information about the epidemiology of AIDS and HIV, the behaviors that spread HIV, and the effectiveness of AIDS prevention efforts. Given the important role that this information plays in understanding the AIDS epidemic, the committee has reviewed what is known about the quality of exist- ing data on behaviors associated with HIV transmission and provides recommendations on steps that can be taken to improve this information. Sampling Much of what is now known about the epidemiology of AIDS comes

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28 ~ AIDS: THE SECOND DECADE from small-scale, local studies targeted at subgroups thought to be at high risk of infection. Participants in these studies are recruited from a variety of sources from the clientele of local clinics or treatment facilities, from the membership rosters of local organizations, from newspaper advertise- ments and physician referrals, and occasionally from "street sampling." The yield from this research has been remarkably rich. As valuable as these studies are, however, the data they provide cannot address many important public health questions that arise from the problem of AIDS, such as how large is the epidemic and what is the potential for general spread of HIV infection? To answer questions such as these, lessons learned from local studies of special subgroups must be applied in large-scale investigations of pop- ulations that are chosen not because of convenience or ease of access but because of their importance in understanding the course of the epidemic. To review the adequacy of current survey work in the general population and in local areas, the committee reviewed 15 selected surveys. Most of these studies were initiated after the AIDS epidemic began and rep- resent responses to the need for population-based estimates of behaviors known to be associated with HIV transmission. The committee assessed the execution of each survey's sampling plan and, in particular, the rat of participation (i.e., the response rate). The committee also considered the available evidence on nonresponse bias; that is, the disproportionate underrepresentation of identifiable segments of the population, especially those who differed on the characteristics being measured. Response rates are used as a "yardstick" for assessing the accuracy of survey estimates because high response rates reduce the influence of selective participation in surveys and hence the potential for bias in the estimates. There was substantial variation in the response rates achieved in the surveys examined by the committee. No strong associations were observed, however, between response rates and modes of data collec- tion (i e., personal interviews, telephone interviews, or self-administered questionnaires given in the context of a personal interview). There were also no substantial associations between response rates and the scope of the sampling (local versus national), the number of questions on sexual behavior in the interview, or, surprisingly, whether sample persons were asked to donate blood specimens for serologic testing. From the review conducted by the committee, it appeared that "pig- gybacking" a small number of questions about sexual behavior onto estab- lished large-scale surveys is a particularly feasible strategy for obtaining estimates of the prevalence of certain sk factors for sexual transmission Of HIV in general populations. Relatively high rates of participation have

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SUMMARY | 29 been achieved by several established surveys. The ingredients for such success are well known to survey practitioners: prior experience with similar surveys, continuity of interviewing staff, a high "target response rate" combined with a field operation that promotes diligent follow-up of nonrespondents, and adequate resources. Under these conditions, it is possible to achieve response rates for small subsets of sex-related items that are similar to the rates achieved by well-conducted surveys that do not inquire about sensitive personal behaviors. The collection of survey data through telephone interviews has be- come an increasingly popular alternative to face-to-face interviewing (telephone interviews are less expensive and easier to conduct as a result of developments in sampling and interviewing technology). Experience with surveys of sexual behavior conducted by phone is too limited, how- ever, to determine the levels of participation that can be achieved in such surveys and whether the somewhat lower response rates in the few available cases are a generic feature of telephone surveys or simply the result of early and somewhat idiosyncratic first attempts. In view of the substantially lower cost of telephone as compared with face-to-face surveys, as well as the limited scope of current experience, carefully designed experiments should be undertaken to test the feasibility of this methodology for surveys of sexual behavior in general populations. SeroprevaTence surveys involve the application of well-established principles of probability sampling and survey methodology to the problem of collecting sample blood specimens in such a way that population prevalence can, in theory, be estimated with known margins of error. However, the practical difficulties involved in mounting a seroprevaTence survey on a local or national basis are formidable. Not the least of these are the problems of potentially high levels of noncooperation among sample persons and possible correlations between participation and HIV serostatus. A trade-off between streamlined designs that maximize response rates and intensive epidemiological investigations with lower response rates is apparent in the available examples of such surveys. Survey designs that limit the demands on respondents by making participation relatively easy, anonymous, and nonthreateningmay be a wise choice. Further testing and refinement of this approach on a larger scale will establish whether it constitutes a feasible design for a national survey. Nonresponse Bias Nonresponse bias occurs when participation in a survey is selective with respect to a characteristic whose distribution is to be estimated from the survey responses. A high response rate tends to minimize the effects of

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30 ~ AIDS: THE SECOND DECADE such selectivity on survey estimates as Tong as the procedures used to attain it do not in fact increase the correlation between the characteristic of interest and the act of participation. Response rates in most surveys, however, usually are not sufficiently high to justify ignoring problems of . . . . se ect~ve participation. What is presently known about the structure of nonresponse bias in sex and seroprevalence surveys comes from two kinds of compansons: comparisons of survey estimates with census data and internal analyses of the correlates of different levels of nonresponse. There is an appar- ent positive correlation between years of schooling and participation in several of the surveys, but the committee could detect few other regular- ities in the available analyses of deviations between survey estimates and census figures. In any case, a good match between census and sample survey distributions, although encouraging in some respects, does not imply unbiased estimates of prevalence rates for sexual behavior or HIV infection. In many surveys, it is possible to study nonresponse at a given stage of the survey by looking at information collected at a previous stage- for example, by comparing responses given by respondents and nonrespon- dents in the preliminary interview or comparing the characteristics of persons who agreed to give a blood specimen with those who refused. In reviewing selected surveys, the committee found many opportunities for such comparisons, few of which had been seized. The addition of a careful study of nonresponse bias to the short sexual behavior component of the 1988 National Opinion Research Center's General Social Survey (GSS) is an important exception. In the GSS, nonresponse biases were found to be quite small among those variables most closely associated with differences in sexual behavior. Although these results are infor- mative about the nature of nonresponse in this one survey, it would be premature to generalize them to other surveys. Rather, careful studies are required of the effects of nonresponse in a wider range of sexual behav- ior and seroprevalence surveys. In this regard, the committee encourages further exploitation of existing data from past sex and seroprevalence surveys to learn more about the structure of nonresponse. Validity and Reliability Behind every e-way tabulation, logistic regression, or other analytical model used in AIDS behavioral research lies a human encounter between two individuals, an interviewer and a respondent. The situational, cogni- tive, social, and psychological factors that arise within that interpersonal exchange affect the answers that are given and the data that are thereby

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SUMMARY ~ 31 generated. To understand the sexual and drug-using behaviors that are at issue in survey research on HIV transmission, one must ultimately con- front the uncertainties introduced by this question-and-answer process. Although there is a substantial literature on the effects of nonsam- pling factors in survey measurements, the problems encountered in study- ing sexual and drug use behavior are unique in some respects- most no- tably, with respect to validation of responses. There is reason to believe (and empirical evidence to support such a belief) that some respondents conceal behaviors under even the most benign of survey circumstances. This possibility must be given considerable weight in the face of statutes in many states that classify some sexual behaviors (including male-female and male-male oral and anal sex) as crimes. Finally, there is the possibil- ity that behaviors engaged in while the respondent is under the influence of drugs or alcohol may be poorly recalled, if at all. Given these con- siderations, lingering concern about the trustworthiness of key survey estimates is virtually inevitable. In light of such concern, the committee reviewed the available evidence on the accuracy of self-reports of sexual and drug use behaviors. Sexual Behavior There is only a very limited range of evidence that can be collected to provide independent corroboration of the validity of self-reported sexual behaviors. One type of evidence is the reports of sexual partners. Studies by Kinsey and several later investigators find a rather high degree of congruence between reports of sexual partners. Indeed, in some of the instances, the levels of agreement are striking. Although partners provide the most obvious source of independent information on sexual behavior, they are not the only validation method that has been used. One investigator, for example, went to unusual lengths (including the use of a lie detector) to motivate respondents to correct"misreports" they made in completing a survey questionnaire. The "corrections" made to the original survey data provide an indication of the types of reporting biases that afflict typical survey measures. For every sexual behavior included in this study, a substantial fraction of the respondents (college men) misreported their actual behaviors. Thus, although virtually every male ultimately indicated that he had masturbated, approximately one out of every three In the initial survey denied masturbating. Similarly, although 22 percent of these college men ultimately reported some history of male-male sexual contact, the majority of these men initially denied such contact. In two instances, analyses have been reported of measurements of

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32 | AIDS: THE SECOND DECADE sexual behavior derived from independent replications of surveys on sam- ples of the same population. Although some deviations could be detected statistically between the measurements made in different surveys, the dis- crepancies found were actually quite small. Although only two behaviors were compared (age at- first occurrence of heterosexual intercourse and number of partners in past year), these examples demonstrate that sur- veys can produce replicable measures of sexual behavior in well-defined populations. A parallel approach to the replication of entire surveys on new sam- ples from a population is the repeated measurement of a stable character- istic of the same respondent. Results of such studies indicate substantial levels of consistency between answers to questions about sexual behav- ior obtained at two different points in time. The observed consistency, however, is not as high as the consistency obtained for some other topics, such as smoking behaviors. Drug-Using Behaviors The methodological difficulties encountered in studying drug use be- haviors are similar to those found in studying sexual behaviors. As in measuring sexual behaviors, a major problem in measuring injection behaviors arises from the fact that researchers usually cannot directly ob- serve the behaviors of interest and thus must rely on self-reports. Several studies have compared reports of drug use with the results of urinalysis. Evidence from these studies suggests that there are moderate levels of underreporting of drug use. Generalizations from such studies are con- strained by the fact that past research has usually examined a relatively restricted range of behaviors typically focusing on drug use per se in populations that were already identified as ex-drug users. In AIDS re- search, however, questions of particular interest include not just whether drugs are used but how they are administered, how often needles are shared or cleaned, and so forth. Little is known about the accuracy of responses to more fine-grained questions such as these, although some data suggest that respondents share needles at a rate higher than they report to researchers. Summary of Fintlings Although there is ample evidence of error and bias in existing surveys of sexual behavior and such evidence should be of concern to investigators, some important and promising conclusions can nevertheless be drawn from this body of work. First, there appears to be little question that surveys of sexual and

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SUMMARY ~ 33 drug use behavior can enlist the cooperation of the vast majority of the American public. Second, the recent literature contains two instances in which inde- pendently conducted surveys of aspects of sexual behavior (age of first intercourse and number of sexual partners in past year) produced reas- suringly similar results. This similarity was achieved despite variations in survey methodology. Third, in most sexual behavior and drug use surveys, it will be difficult (if not impossible) to obtain convincing evidence of measurement validity. The committee finds nonetheless that the research literature contains several important demonstrations of the validity of behavioral measures. These results are certainly encouraging, but there is also a variety of other evidence that suggests that some behaviors may be considerably underreported in surveys. For example, although the data are limited, it appears that male-male sexual contacts may be significantly underreported (at least by college student populations). Finally, there is a fairly large body of research addressing the consis- tency of responses over short periods of time in survey reports on various aspects of sexual behaviors. These studies have generally demonstrated moderate levels of response consistency over time. It must be noted, however, that consistency in itself does not guarantee accuracy. Improving Measurements The above evidence leads naturally to questions regarding how to im- prove the reliability and validity of self-reported data on these behaviors. To begin answering those questions, the committee recommends that the Public Health Service anti other organizations supporting AIDS research provide increased support for methodological research on the measurement of behaviors that transmit HIV. Such research should consider inferential problems introduced by nonresponse and by nonsampling factors, including (but not limited to) the effects of question wording and question context, the time periods and events that respondents are asked to recall, and the effects of anonymity guarantees on survey responses. In addition to adopting procedures that ensure that respondents can understand the questions they are being asked, it is desirable to supplement self-reports with alternative mea- sures whenever possible. Ethnographic observations, physical evidence, skills demonstrations, and reports of "significant others" can provide important data on the biases that may affect key measurements. The committee recommends that, whenever feasible, researchers supple- ment self-reports in behavioral surveys on HIV transmission with

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34 ~ AIDS: THE SECOND DECADE other indicators of these behaviors that do not rely on respondent reports. Furthermore, the committee recommends that, where ap- propriate, researchers embed experimental studies within behavioral surveys on HIV transmission to assess the effects of key aspects of the survey measurement process. Although it is impossible to provide firm guarantees as to the ben- eficial effects of any particular tactic, the committee believes that there is strong presumptive evidence to indicate that a considerably larger in- vestment of resources needs to be made in exploratory work prior to the fielding of major survey investigations. For surveys of behaviors that risk HIV transmission, this lack of exploratory research is particularly troubling, given the underdeveloped state of research in this field. In this regard, the committee notes that some of the questionnaires it re- viewed made impossible demands on the memory of respondents, an unfortunate error that would have been detected if the questionnaires had received more thorough pilot testing. The committee recommends that researchers who conduct behavioral surveys on HIV transmission make increased use of ethnographic studies, pretests, pilot studies, cognitive laboratory investigations, and other similar developmental strategies to aid in the design of large-scale surveys. SYNOPSIS AND MAJOR RECOMMENDATIONS Throughout the report the committee reviews a variety of issues and presents a series of recommendations. Because the material is presented in some detail, the committee wishes to highlight some of the major points here. The committee finds that the broadening scope of the AIDS epidemic calls for increased prevention efforts to reach a variety of subpopulations at differential risk, such as adults and adolescents, men and women, ho- mosexuals and heterosexuals. The committee is particularly concerned about the epidemiological evidence that finds a disproportionate burden of disease among minority subpopulations. Therefore, the committee rec- ommencIs that the agencies of the Public Health Service encourage and strengthen behavioral science research aimed at understanding the transmission of HIV in various black and Hispanic subpopula- tions, inclutiing men who have sex with men, drug users anti their sexual partners, and youth. The committee further recommends that the PHS develop plans for appropriate interventions targeted toward these groups and support the implementation of intervention strategies (together with appropriate evaluation components) in both demonstration projects and larger scale efforts.

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SUMMARY | 35 Adolescents and women are other groups that present both impor- tant opportunities to prevent future disease and challenges to providing effective intervention programs. It is during the adolescent years (and sometimes earlier) that many of the behaviors that risk transmission of HIV are initiated. For programs to be most effective, however, teens must be reached before they begin the behaviors that put them at risk. Thus, the committee recommends that AIDS prevention programs make special efforts to reach very young teens and, in some subpopula- tions, to reach youth before they enter adolescence. Thus far over the course of the epidemic, a considerable proportion of the resources allo- cated to prevent horizontal and vertical transmission among women have been devoted to counseling and testing programs. Yet important ques- tions remain about how this service is delivered and what impact it has on subsequent risk-associated behaviors. Therefore, the committee recom- mends careful review of the goals of testing and counseling programs for women of childbearing age and the implementation of research to ascertain the effect of such programs on future risk-taking behavior. Moreover, the committee recommends that the Public Health Service support research to develop protective measures other than condoms for preventing HIV transmission during sexual contact specifically, methods that can be used unilaterally by women and methods that will be acceptable to both men and women who do not currently use condoms. Designing and implementing relevant and effective programs re- quires knowledge about the targeted population and the risk-associated behaviors of concern. Thus, the committee recommends: that the Public Health Service encourage and support behavioral research programs that study the behaviors that transmit HIV infection and that the PHS develop and evaluate mechanisms for facilitating and sustaining change in those behaviors; that intervention programs incorporate planned varia- tions that can be carefully evaluated to determine their relative effectiveness; that the PHS regularly summarize the data derived from currently funded behavioral and epidemiological research on AIDS (in terms of incidence of infection and high-risk behaviors) to determine intervention priorities for various subpopulations at risk; and that all agencies of the PHS that are currently funding intervention programs and evaluation research regularly

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36 ~ AIDS: THE SECOND DECADE summarize the data derived from these studies to deter- mine which, if any, programs can be recommended for wider dissemination. Understanding the behaviors that transmit the virus depends on the availability of valid and reliable data regarding those behaviors, including the distnbution and variation of the behaviors across venous subpopula- tions. Unfortunately, the data on AIDS-related behaviors are extremely limited, and most are out of date. Moreover, these data rely for the most part on self-reported information of unknown quality. Consequently, the committee recommends that the Public Health Service and other organizations supporting AIDS research provide increased support for methodological research on the measurement of behaviors that transmit HIV. Such research should consider inferential problems introduced by nonresponse and nonsampling factors, including (but not limited to) the effects of question wording and question context, the time periods and events that respondents are asked to recall, and the effects of anonymity guarantees on survey responses. In addition to the diversity of at-risk groups, the committee wishes to note the dynamic nature of the patterns of behavior that contribute to the spread of infection. The role played by IV drug use in HIV transmission has been apparent since the early years of the epidemic, but only recently has there beer a growing appreciation of the role of over drugs, such as crack and cocaine, in sexual transmission of the AIDS virus. Therefore, the committee recommends that the Public Health Service establish mechanisms across its agencies for rapid identification and assessment of the relationship of new drug use problems to the spread of HIV. Given the continued threat of HIV and AIDS and given the lack of biomedical solutions to this serious health problem, the committee finds that sustaining behavioral change and preventing relapse are issues that require immediate and sustained attention. Thus, the committee recommends that the Alcohol, Drug Abuse, and Mental Health Administration focus research efforts on AIDS-related relapse prevention, including the determinants of such relapse and the role that alcohol and other drugs play in the return to unsafe sexual and injection practices. There has been substantial progress in reducing the risks of HIV transmission associated with the blood supply, progress achieved through technological solutions, augmented by behavioral interventions. Yet, as the risk of exposure to contaminated blood and blood products diminishes, the issue of maintaining an adequate supply of blood arises. Efforts to exclude at-nsk donors must take into account the need to maintain

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SUMMARY | 37 sufficient quantities of blood donated by individuals who pose no risk to the blood supply. The committee recommends that: blood collection agencies strive for clearer communi- cation of the exclusion criteria to potential and actual donors; blood collection agencies work to increase donation by those who can safely give and abstention by those who are at even minimal risk through recruitment approaches that stress altruistic appeals rather than the use of com- petitions, incentives, and social pressure; the National Heart, Lung, and Blood Institute con- tinue its support for research to investigate why some donors with identifiable risk factors continue to donate while others without risk factors inappropriately exclude themselves; and physicians and blood banks encourage autologous dona- tion in cases in which surgery is anticipated. Reducing the exposure of potential transfusion recipients to homol- ogous blood can be accomplished in several ways, depending on the circumstances that prompt transfusion. Educating physicians and their patients, establishing guidelines for blood use, and modifying prescribing behavior are necessary to achieve this goal. .