AIDS The Second Decade (1990) / Chapter Skim
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6 Methodological Issues in AIDS Surveys
6 Methodological Issues in AIDS Surveys
Pages 359-472
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From page 359... ...
The committee's aim in presenting this material is to provide researchers conducting AIDS surveys or analyzing data collected in such surveys with a detailed review of the current state of methodological research in this area. Readers who seek only a synopsis of the committee's conclusions and recommendations may wish to consult pages 27-34 of the summary chapter.
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From page 360... ...
. Surveys that inquire about sexual behaviors or IV drug use differ in several ways from the foregoing example, and these differences provide a much greater challenge to the survey (or question-and-answer)
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From page 361... ...
HIV infection occurs through the joint operation of the biology of this particular infectious virus and the human behaviors that transmit it. In the absence of vaccines, aZZ interventions that seek to retard the spread of HIV infection focus on changing human behaviors to diminish the probability that the virus will be transmitted.
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From page 362... ...
requires asking questions about these risky behaviors. This activity, in turn, raises a host of methodological issues that are germane to survey research of all types plus some questions Hat are specific to surveys of drug use and sexual behavior.
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From page 363... ...
Such examples indicate that the problems AIDS researchers confront when they seek to assess sexual arid drug-us~ng behavior are not unique in He urinals of scientific measurement. As Quinn McNemar observed more than 40 years ago, "Lalll measurement is befuddled win error.
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From page 365... ...
From these studies, researchers have identified the principal mechanisms of HIV infection (i.e., transmission through sexual contact, sharing injection equipment in IV drug use, transfusion of contaminated blood products) ; verified sexual transmission of HIV from male to male, female to male, and male to female; measured the efficiency of transmission in specific kinds of sexual contacts; and discovered some of the basic features of the long natural history of this devastating disease.
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From page 366... ...
The authors of this suggestion were a committee of the Commission on Statistical Standards of the American Statistical Association. At the invitation of Dr.
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From page 367... ...
high response rates reduce the influence of selective participation in surveys and hence the potential for bias in the estimates, and (2) for a given target sample size and sample design, the higher the response rate, the larger the actual sample and the smaller the standard error of estimate.
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From page 368... ...
Scope of the Review The committee chose 15 surveys for its review, including some that are national in scope and some that target local populations. Most of these studies were initiated after the AIDS epidemic began in response to the need for population-based estimates of sexual behaviors known to be associated with HIV transmission.
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From page 369... ...
For the most part, the questions used in recent surveys (i.e., those initiated after the AIDS epidemic began) attempt to measure the occurrence of sexual behaviors associated with HTV infection and transmission and fall into three general categones: sexual orientation (with a focus on homosexuality)
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From page 371... ...
o ~ - ~ oc ~ c c w,~ O O ,ca = y O 3 ~ C)
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From page 373... ...
c~ c~ ~ c~ ~ w ~ o v ^-' ~ _ ~ ·-= — — ce ~ — ~ ~ t~ ~ ~ ~ o — 3 w ._ ._ C ._ _ ~ W — ~ — 3 ~ ~ ~ ~ ·— · ~ 1 ~s _ ~ ° Ce ~ ° W .
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From page 374... ...
Item nonresponse rates were generally low or not reported in the available survey documentation. As noted earlier, the response rate in a study is conventionally used as one yardstick for measuring the potential accuracy of survey estimates.
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From page 375... ...
(The reader should note that the response rates reported for surveys no. 4 and 10 are probably overestimates; for details, see the section "Use of Telephone Surveys" below.)
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From page 376... ...
Nonetheless, they share certain characteristics that may help to explain why they achieved relatively high rates of participation: they are each part of a series of periodic surveys that have consistently had good response rates; the sexual items consist of a relatively small set of "add-on" questions; the surveys are conducted by the same survey organizationsS and to some extent by the same supervisory and field staff that have been responsible for previous surveys in the senes; and the field procedures include provisions for large numbers of callbacks and special attention to the conversion of refusers. The 1988 GSS is the fourteenth in a series of annual opinion surveys conducted by the National Opinion Research Center (NORC)
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From page 377... ...
. · Have your sexual partners in the last 12 months been: exclusively male, both male and female, exclusively female?
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From page 378... ...
Household rosters were missing for approximately 4 percent of the households included in the NHIS target sample. iOThe NSFG traditionally had some items on sexual behaviors (e.g., age at first intercourse)
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From page 379... ...
Although response rates for the two methodologies tend to converge when unanswered telephone calls are ignored, acceptable standards (e.g., Council of American Survey Research Organizations, 1982) for reporting response rates mandate that a fraction of the numbers not contacted be included in the denominator when calculating response rates for telephone surveys.
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From page 380... ...
9 and 10) —one of which was conducted in San Francisco, the other In Seattle—are examples of the use of targeted sampling of phone numbers arid telephone interviewing to find and interview persons who may be considered to be at higher than average risk of HIV infection.
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From page 381... ...
Although there is no mention of the number of households that were not contacted or of the eligibility rate per contacted household, the authors hazard the opinion that "awaits a sample size of 500, results were protectable to the universe of selfidentifying gay and bisexual men in San Francisco within +4.5% at the 95% level of confidence" (Communication Technologies, Inc., 1987:251. The 1985-1986 Seattle survey was a pilot study of the use of telephone interviewing to collect data on sexual behavior in subgroups of the general population who were likely to be at risk of acquiring HIV infection.
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From page 382... ...
. Any respondent who reported one or more of these risk factors was asked additional questions about specific risk behaviors.
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From page 383... ...
Survey estimates of the distribution of behaviors associated with HIV transmission, combined with epidemiological findings on the transmission efficiency of HIV in sexual contacts and biological aspects of the natural history of HIV infection, are the raw material for modelbased inferences about the future spread of AIDS in known risk groups and in populations not yet considered to be at risk (May and Anderson, 1987; Anderson and May, 1988; May, Anderson, and Blower, 1989; Turner, Miller, and Moses, 1989:Ch.
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From page 384... ...
The most attractive design for direct measurement of the prevalence of infection is the seroprevalence survey.~4 A seroprevalence survey applies well-established principles of probability sampling and survey methodology to the problem of collecting sample blood specimens with the aim of estimating the prevalence of infection in a population. In theory, such surveys could eliminate most of the outstanding uncertainties regarding the size of the AIDS epidemic, the prevalence of infection in major risk groups, and the degree to which HIV has entered populations that are not presently considered to be at significant risk for infection.
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From page 385... ...
12 in Table 6-1) is believed to be the first seroprevalence survey of HIV infection conducted in the United States.
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From page 386... ...
After signing a written informed consent document, sample persons were interviewed at home using a standardized questionnaire; they were then asked for a blood sample (obtained by venipuncture) and examined for signs of HIV infection.
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From page 387... ...
The Allegheny County pilot study indicates that relatively high response rates can be obtained in seroprevalence surveys that involve public (e.g., TV news) appeals to participate, that make limited demands on participants' time and that offer substantial monetary incentives.
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From page 388... ...
The committee's review likewise indicates that the response rates achieved in contemporary sex and seroprevalence surveys leave ample opportunity for selective participation to affect the validity of survey estimates of sexual behavior and HIV seroprevalence. (The reader should note Hat response bias that is, misleading or inaccurate survey responses—can have similar effects.
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From page 389... ...
If the marital status of male nonrespondents is known (from, for example, a household enumeration interview) and if there were a good basisl7 for the belief that, for any particular marital status, the sexual behaviors of respondents and nonrespondents were similar, sample estimates of the distribution of sexual behavior might be adjusted, using imputation or maximum likelihood procedures, to adjust for this nonresponse bias.
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From page 390... ...
In any case, a good match between census and sample survey distributions, although encouraging in some respects, does not guarantee that estimates of prevalence rates for sexual behavior or HIV infection are unbiased. The other major source of information about nonresponse bias comes from analyzing the characteristics associated with nonresponse at different stages of a survey interview.
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From page 391... ...
NONSAMPLING ISSUES IN AIDS SURVEYS This section focuses on the survey measurement procedures that yield data for basic and applied studies of the behaviors that transmit HIV. The emphasis here is on nonsampling factors that affect the quality of these data.
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From page 392... ...
(This type of nonresponse is discussed in the preceding section.) Nonsampling factors that affect measurements include misunderstanding of questions, respondent unwillingness to reveal sensitive information, interviewer mistakes in reading questions, clerical and other errors made during coding and processing of data, and so forth.
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From page 393... ...
that respondents do provide reasonably consistent responses to survey questions on sexual behaviors. When it comes to validation of responses, however, the problems are much more numerous, and they introduce considerable uncertainty into the interpretation of almost all survey data derived from self-reports of sexual behavior and drug use.
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From page 394... ...
That is to say, questions such as, "Have you had sexual contact to orgasm with another man in the last week? " may be more prone to bias induced by the sensitivity of Be topic than by He respondents' inability to understand the question or remember the event.
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From page 395... ...
and the reporting of 24 In 1986, the Supreme Court ruled that states could enforce criminal sanctions against consensual homosexual behaviors, even when practiced by adults in the privacy of their own home (Bowers v. Hardwick, No.
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From page 396... ...
are, after all, of considerable interest. Indeed, these estimates figure centrally in two of the most important research challenges of the epidemic's second decade: determining whether there are declines over time in the incidence of sexual behaviors that risk transmitting HIV, and assessing the effectiveness of AIDS education and prevention programs by comparing the behaviors of persons who participate in those programs with the behaviors of those who do not.
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From page 397... ...
As discussed below, however, there may be indirect approaches that could be used for such assessments. 251~here is also evidence, however, that in some interventions directed toward IV drug users, increased rapport between clients and program staff over time results in more honest reporting of risky behaviors.
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From page 398... ...
It recommended a careful review of these data systems and, if necessary, an increase in resources to improve them (Turner, Miller, and Moses, 1989:1671. Furthermore, for any group, the trends in STD rates over time will reflect phenomena such as the changes, if any, in the behaviors of group members that expose them to infection, trends in the rates of STDs among the population from which the group selects its new sexual contacts, and changes in reporting practices.
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From page 399... ...
AIDS SURVEYS ~ 399 and, more important, alternative ways of viewing the error structure of measurements for variables, like intelligence, that are never subject to direct observation. The psychometric literature is vast, and it would be impossible to summarize it here.
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From page 400... ...
While these three psychometric notions of validity can be helpful in approaching the problems involved in validating survey measures of sexual behaviors, their past use has sometimes been less than optimal. One of the most important failings results from overreliance on correlation coefficients in reporting on the validity of measurements.
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From page 401... ...
EMPIRICAL STUDIES OF SEXUAL BEHAVIORS Validation 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. In the past, three broad types of research evidence have been collected: · partner reports, in which regular sexual partners respond to the same questions as the study respondent; · "invalidation evidence," which is derived from longitudinal studies in which it is possible to obtain some measure of reporting accuracy by examining the temporal patterns for impossible temporal sequences (e.g., persons who report having engaged in sexual intercourse when interviewed at age 15 but who report at a later age that they have never had intercourse)
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From page 402... ...
402 ~ AIDS: THE SECOND DECADE TABLE 6-2 Findings of Kinsey et al.'s (1948) validation study of sexual behaviors reported by spouses.
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From page 403... ...
With some exceptions, these studies do not cover as comprehensive a range of sexual behaviors as Kinsey explored. They are, nonetheless, perhaps of more relevance for understanding the qualities of the behavioral data that are routinely used in AIDS research.
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From page 404... ...
1 At co ~ 5 [L X V: o o C)
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From page 405... ...
1 4os eC · ~ 2— S — 9 — '— — o ;> ~ — C.)
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From page 406... ...
, for example, requested that the gay men in their study report the total number of sexual encounters they had with a particular partner and the total number of times (or percentage of encounters) during which they engaged in specific sexual behaviors.
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From page 407... ...
(It should be emphasized that the criterion measure was not the polygraph judgment but rather the subjects' behavior in "correcting" their answers to the questionnaire when confronted with the polygraph.~35 Table 6-4 presents selected results from this study. It will be seen that for every measurement a substantial fraction of the sexual behaviors that were finally reported were reported only after the possibility of lie detection was introduced.
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From page 408... ...
who: (a) report selected sexual behaviors when confronted with lie detector, (b)
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From page 409... ...
Because of the dearth of basic research on sexual behavior in particular and the lack of investment in methodological research in general, there is no ample stock of material from which to make such comparisons. There are, however, two examples that demonstrate the important point that survey measurements of sexual behaviors can produce reliable measures of behavior in well-defined populations.
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From page 410... ...
. Westat for the National Center for Health Statistics (NSFG in Figure 6-3~; and · the 1983 wave of the National Longitudinal Survey of Youth conducted by the National Opinion Research Center (NORC, University of Chicago)
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From page 411... ...
Respondents in the National Longitudinal Survey were asked: At what age did you first have sexual intercourse? (Source: Kahn, Kalsbeek, and Hofferth' 1988:193, Table 3)
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From page 412... ...
As for the discrepant results of the longitudinal survey, surveys that perform repeated measurements of the same respondent may have many characteristics that can affect typical survey measurements. At a minimum, the design of the longitudinal survey must not only accommodate nonresponse at the initial interview stage but is also subject to attrition of respondents from the sample over time.
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From page 413... ...
In this five-way tabulation, once the demographic marginals of the two surveys were made comparabie,43 it was virtually impossible to (liscHminate statistically among the results obtained in the two surveys with regarfl to the number of sexual partners in the last year or in the patterns of association found between this variable an] maOta} status, gender, or age.44 Replication of Measurements Using Same Respondents A parallel approach to the replication of entire surveys on new samples from a population is the repeated measurement of a (stable)
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From page 414... ...
, for example, report test-retest reliabilities for two administrations of a questionnaire asking about sexual orientation, sexual behaviors, and change in sexual behaviors. Respondents were 116 gay men participating in an HIV study being conducted at the Fenway Community Health Center in Boston.4s Compared with the test-retest reliabilities of .94 obtained for questions about smoking behavior and .79 for dietary habits, the reliabilities for reports on sexual behaviors were in the range of .40 to .99.
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From page 415... ...
Although the reliability analyses reported in Table 6-5 encourage the belief that respondents can report consistently on their sexual behaviors, they do not, in themselves, tell anything directly about the systematic distortions that may occur in reporting. In an enlightening analysis of similar test-retest data, Rodgers, Billy, and U6ry (1982)
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From page 420... ...
Changes in the illicit drugs in most common use can have important implications for HIV transmission. Studies presented in 1988 and 1989, for example, indicated that the injection of cocaine was associated with elevated rates of HIV infection (Chaisson et al., 198S, 1989; Des lariats end Fnedman, l98Sb; Fnedman et al., 1989; Novick et al., 1989~.
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From page 421... ...
, for example, report that some drug users disinfect their syringes by using bleach before and after sessions of sharing them with others but not between use by different persons.) Clarifying some of the ambiguities in survey measurements of these behaviors may eventually explain why longitudinal studies have failed to demonstrate a relationship between needle cleaning and rates of seroconversion among injection drug users (see, for example, Moss et al., 19891.
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From page 422... ...
Response bias, however, is a serious problem in such research. Because of such potential biases, there has been ongoing concern among drug use researchers about the accuracy of injection drug users' self-reports.
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From page 423... ...
found small biases in the opposite direction (i.e., more respondents reported drug use than were 5iCoefficient reported Is kappa (see Bishop et aL, 1975:395)
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From page 424... ...
It is quite possible that surveys of such general populations may be subject to a rather different pattern of bias and errors than that afflicting the surveys included in Table 6-6.54 The populations sampled in Table 6-6 were all drawn from groups who were publicly identified as drug users. Because these respondents were already labeled as users of illicit Mugs, not only by researchers but by treatment personnel and the criminal justice system, they may have been less motivated to conceal drug use.
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From page 427... ...
1 427 (I-, <~ ~ — d — oo O _ _ ,~ ,~ _ ~ An, Cal ~ ~ ~ ~ .
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From page 428... ...
Worth and colleagues (1989) , for example, found that women drug users tried to be "good survey takers." After participating in an AIDS prevention group they tended to give responses indicating more frequent risk taking.
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From page 429... ...
This similanty was achieved despite vanations in survey methodology. These results, if repeated across a wider range of measurements, provide salutary evidence that surveys of AIDS risk behaviors can, indeed, provide replicable measurements that is, different investigators using roughly similar methods to survey the same population can obtain equivalent results.
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From page 430... ...
In designing surveys, researchers should be sure that their survey questionnaires (as well as their consent forms, information sheets, etc.) are readable and, in particular that the difficulty of the materials does not exceed the reading level of their subjects.
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From page 431... ...
For example, Bardoux and colleagues (1989) interpreted a declining incidence of hepatitis B among injection drug users in Amsterdam as a resection of decreases in needle-sharing and related risk behaviors among that population.
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From page 432... ...
For surveys of behaviors that risk HIV transmission, this lack of exploratory work is particularly troubling, given the underdeveloped state of research in this field. In this regard, the committee notes that some of the questionnaires it reviewed made impossible demands on the cognitive capacities of respondents, an unfortunate error that would have been detected if the questionnaires had received more thorough pilot testing.
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From page 433... ...
, there is little doubt that researchers' appreciation of the problems that attend key measurements can be sharpened by greater use of exploratory studies prior to the launching of major surveys. Among the techniques that can be profitably employed are ethnographic studies and focus groups whose aim is to explore the frames of reference and language that respondents use in approaching a given topic area; pretests and pilot studies that explore the respondents' understanding of preliminary versions of questionnaires; and cognitive research strategies that detail the limits of recall and the strategies respondents use in answering questions that demand recall of events that are not directly accessible (e.g., how many sexual encounters have you had with John in Me past two years?
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From page 434... ...
Pilot Studies Survey researchers typically distinguish between two types of exploratory studies. Pilot studies are commonly semistructured inquiries conducted prior to the design of the final (or penultimate)
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From page 435... ...
on the willingness of respondents to discuss their sexual behaviors. These British investigators learned several valuable lessons from their pilot work, which used semistructured interviews with 40 respondents.
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From page 436... ...
· There was a strong preference among respondents for use of formal rather than street language in discussing sexual behaviors. Furthermore, although terms such as penis and vagina were well understood, some of the terminology that has become standard in the epidemiological literature was quite foreign to respondents (e.g., vaginal sex)
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From page 437... ...
In beef, three types of supplemental data were collected during the pretests: · Coding of behaviors of interviewer and respondent: survey interviews were recorded, and relevant aspects of the survey interview were coded to indicate whether the interviewer asked the question as written, whether the respondent asked for clarification, and so forth. Systematic coding of the pretest interviews provides useful data for identifying questions that pose special difficulties for the interviewer or the respondent, or both, and that may need to be redesigned.
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From page 438... ...
In that regard the committee notes that two examples used previously may be atypical of the types of information in which AIDS researchers are most interested. Questions regarding chronological age and sexual activity during the past day (or week)
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From page 439... ...
The last year in particular has witnessed publication of several studies that used such techniques to evaluate and improve survey measurements of health-related and other events (Brewer, Dull, and lobe, 1989; Lessler, Tourangeau, and Salter, 1989; Means et al., 1989; Tucker et al., 19891. Yet, although these techniques offer researchers new possibilities to "take account" of the effect of the recall strategy and belief factors in assessing responses, such a task is difficult and may present problems for which there are no easy solutions.
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From page 440... ...
Not only can these techniques be helpful in preliminary investigations to develop better questionnaires and research designs, but they also provide an important research strategy in their own right for studying questions and populations that may be inaccessible using other research techniques. This chapter concludes with a brief overview of current AIDS research using these techniques.
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From page 441... ...
Examples of Studies Related to HIV Transmission Male-Male Sexual Contacts Anthropological research among Mexicans and Mexican Americans in southern Californian provides a telling example of the benefits of an ethnographic approach to data gathering. Studies of sexual behavior in Mexico indicate that Mexican men who engage in same-gender sex have a strong preference for anal intercourse over fellatio.
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From page 442... ...
Variation in Drug Use Patterns A second example of how ethnographic research may broaden and enhance the knowledge base on hard-to-reach populations concerns stereotypical views of IV drug users. Anthropological descriptions of the diversity of behaviors, social networks, and self-distinctions that exist in different drug-using communities discount the widely held image of the "dope fiend" as a person who devotes his life to acquiring and using drugs.
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From page 443... ...
Rather, observation, recording, and measurement are directed by concepts and theories, and these concepts and ideas are subject to modification and change. Unless ethnographers take what they suppose to be a purely empirical approach to the world, they often have a "double sense" of the way they go about their work: they assume that their ideas are suitable for interpreting other peoples' beliefs but that these ideas, like the beliefs they are intended to interpret, are also the products of particular histoncal and social circumstances.69 The methods used to gather ethnographic data fall into five main categories: · direct observation of daily life on mundane and ceremonial occasions, description of the observed environment (sometimes with detailed accounts of commerce or household economies)
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From page 444... ...
AIDS research presents a special methodological challenge as anthropologists investigate the worlds of men and women who have bisexual and same-gender sexual relations or who may be IV drug users and their sex partners, prostitutes and their clients, male hustlers, prison inmates, and undocumented laborers. Some ethnographic studies have looked at health care workers, insurance companies, or students and staff in schools, but most research concerns populations that are seen as "marginalized"— outside the mainstream, often impoverished, and involved in activities that are illegal or that are seen as deviant.
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From page 445... ...
The protocol of an AIDS intervention project for the sex partners of IV drug users in the predominantly black south side of Chicago, for example, began with a preliminary questionnaire (to gather sociodemographic and epidemiological data) , followed by a longer, open-ended conversation that reconstructed the routines of everyday life and some aspects of the respondent's life history.
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From page 446... ...
For an epidemiologist, however, the chart provides an index of the number of people at risk for HIV infection because it records the frequency of sexual intercourse, the categories of sexual partners (those who live together, those who are lovers or more casual partners, and those involved in prostitution) , and whether contraceptives are used.7i Regional compansons, which are commonly used in ethnographic research, have been rare in the anthropology of HIV infection.
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From page 447... ...
Findings of Ethnographic Research on AIDS Ethnographic research on the spread of HIV infection is still in the preliminary phases of data gathering. Nevertheless, some suggestive patterns appear to be emerging.
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From page 448... ...
and the way in which laws that make carrying a syringe a crime increase the probability that drug users will adopt risky behaviors (Koester, 1989a,b)
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From page 449... ...
The ability of impovenshed women to practice "safer" sexual behaviors, for example, may be particularly circumscribed. Furthermore, very little is known about the interaction between private worlds of erotic behavior and the public domain of shared meanings recently explored by Parker (19891.
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From page 450... ...
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. 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.
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From page 451... ...
(1989) Declining incidence of acute hepatitis B among drug users in Amsterdam may indicate a change in risk behavior.
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From page 452... ...
International Journal of the Addictions 11:719-724. Borgatta, E
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From page 453... ...
(1989) Demographic and behavioral features of HIV infection in intravenous drug users in New York City drug treatment programs: 1985-1988.
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From page 454... ...
(1989) Perception of risk and HIV infection among intravenous drug users (IVDUs)
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From page 455... ...
(1982) On the Definition of Response Rates.
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From page 456... ...
(1989a) Intravenous drug users and maintenance of behavior change.
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From page 457... ...
(1988) The ethnography of needle sharing among intravenous drug users and implications for public policies and intervention strategies.
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From page 458... ...
(1988) Psychosocial predictors of AIDS high risk behavior among intravenous drug users and their sexual partners.
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From page 459... ...
(1989) Endocarditis, subcutaneous abscesses, and other bactenal infections in intravenous drug users and their association with skin-cleaning at drug injection sites.
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From page 460... ...
(1988) Psychological assessment and AIDS research with intravenous drug users: Challenges in measurement.
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From page 461... ...
(1988) A method for assessing needle-sharing behavior in intravenous drug users.
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From page 462... ...
(1989a) The risk of HIV transmission from sharing water, drug-mixing containers and cotton filters among intravenous drug users.
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From page 463... ...
(1988) AIDS prevention among black IV drug users and their sexual partners in a Baltimore public housing project.
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From page 464... ...
(1988) Risk factors for HIV and HBV infections in intravenous drug users.
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From page 465... ...
Development of a strategy to combat HIV contagion among San Francisco intravenous drug users.
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From page 466... ...
K (1988) HIV infection in intravenous drug users: A follow-up study indicating changes in risk-taking behaviour.
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From page 467... ...
(1989) Developing strategies for AIDS prevention research with black and Hispanic drug users.
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From page 468... ...
(1989) Use of a fingersiick paper-absorbed blood sample for HIV serosurveys in intravenous drug users.
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From page 469... ...
(1989) Observations on the importance of social context in HIV transmission among intravenous drug users.
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From page 470... ...
(1989) Women don't wear condoms: Coping with AIDS risk among women partners of intravenous drug users.
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From page 471... ...
85-1402. National Institute on Drug Abuse Research Monograph No.
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