Sexual Risk Reduction for Persons Living with HIV: Research Synthesis of Randomized Controlled Trials, 1993–2004

Abstract

Objective

To conduct a meta-analytic review of interventions to reduce HIV+ individuals’ sexual risk.

Design

Studies were included if they examined a deliberate sexual-risk-reduction strategy in a sample that included HIV+ participants; used a randomized controlled trial design; measured condom use or number of sexual partners following the intervention; and provided sufficient information to calculate effect size (ES) estimates.

Method

Reports were gathered from computerized databases, by contacting individual researchers, by searching relevant journals and conference proceedings, and by reviewing reference sections of obtained papers. Data from 15 studies (N=3,234 participants) available as of November 30, 2004 were included. Effect sizes (ES) were standardized mean differences.

Results

Across the studies, intervention participants exhibited lowered sexual risk relative to control participants on condom use (Mean ES, 0.16; 95% CI, 0.08 to 0.25) but not for number of sexual partners (Mean ES, −0.01; 95% CI, −0.16 to 0.14). Interventions were more successful at increasing condom use if the sample included (1) fewer men who have sex with men (MSM) or (2) younger samples, and (3) when interventions included motivational and skills components.

Conclusions

Behavioral interventions reduced sexual risk especially if they included motivational and skills components. Such interventions have been less effective for older samples, suggesting the need for further refinement to enhance their efficacy. Motivation- and skill-based interventions have not yet been tested with HIV+ MSM who, in general, appear to have benefited less from extant risk-reduction interventions.

Persons infected with HIV can now routinely expect to live longer and healthier lives. With extended longevity, however, comes the challenge of adopting safer sexual practices for many years. Evidence suggests that the majority of HIV+ persons do reduce their risk behavior once they learn that they are infected with HIV. For example, Weinhardt et al.’s [1] meta-analysis of HIV counseling and testing (HIV-CT) programs found that, subsequent to HIV-CT, HIV+ participants increased condom use and reduced unprotected intercourse more so than did HIV− and untested participants. A more recent survey of 3,723 HIV+ people yielded similarly encouraging results. In this study, nearly 85% of HIV+ persons reported that they did not engage in risk behavior with uninfected partners [2].

Although many HIV+ persons reduce risk behaviors subsequent to learning that they are infected, a minority of HIV+ persons find this challenge difficult. For example, in Weinhardt et al.’s [2] sample, 13–19% reported unprotected vaginal or anal intercourse with partners whose serostatus was negative or unknown. Moreover, 18% of injection drug users reported that they had shared injection needles with other partners. Other studies have reported that a minority of HIV+ persons continue risky sexual or drug-use practices [3]; other individuals who are not aware of their serostatus may also transmit the disease. The route of sexual transmission is the leading cause of the approximately 40,000 new infections in the US annually [4–5]; sexual intercourse between men and women results in most HIV-1 infections acquired by adults in sub-Saharan Africa [6]. Transmission through blood transfusions, injections with infected needles, and scarification are thought to represent only a few infections [6].

Risk reduction programs for HIV+ persons have been implemented in many settings but an evaluation of these programs provides mixed evidence of their efficacy. For example, Cleary et al. [7] tested an informational and supportive intervention promoting behavior change with 271 HIV+ blood donors, and reported no advantage of the risk-reduction intervention relative to a control condition. In contrast, Rotheram-Borus et al. [8] evaluated a multi-session group-based intervention for HIV+ adolescents, and reported that adolescents reduced the number of HIV− sexual partners by 50% and decreased the number of unprotected sexual acts by 82%.

The current meta-analysis integrates the available evidence to determine the degree to which prevention programs for HIV+ persons are efficacious. We located controlled intervention studies that addressed risk reduction in samples that included HIV+ persons, and obtained effect size estimates of intervention efficacy. Our primary goal was to determine whether sexual risk reduction programs for HIV+ persons help participants to reduce the number of sexual partners and/or increase condom use. Our secondary goals were to identify moderators of intervention efficacy including intervention components that warrant inclusion and sub-groups for whom the interventions need further tailoring. Such information can provide needed guidance for intervention development and prevention research.

Method

Sample of Studies

We searched for randomized controlled trials (RCTs) using three strategies. First, we searched electronic reference databases (MEDLINE, PsycINFO, AIDSLINE, CINAHL, Dissertation Abstracts Online, and ERIC) using search terms related to HIV interventions (e.g., risk reduction, prevention, seropositive) and sexual risk behavior (e.g., condom use). Second, we used the same search terms in Internet search engines such as Yahoo! and Google through May 26, 2004. Third, we checked HIV-related listservs and the NIH database of grant awardees (CRISP), and we sent requests for papers to individual researchers conducting interventions with seropositive individuals. The goal of these supplemental strategies was to ensure the comprehensiveness of the reference database searches. Studies that fulfilled the search criteria and that were available as of November 30, 2004 were included. In some cases, information about study interventions was taken from several publications or unpublished reports. All studies included in our final sample were published reports, although we considered both published and unpublished studies in our search.

Selection Criteria

Studies or portions of studies were included if they (1) examined a deliberate HIV-risk-reduction strategy in a sample that included HIV+ participants; (2) used a RCT design; (3) measured condom use or number of sexual partners; and (4) provided sufficient information to calculate effect size (ES) estimates. Studies were excluded if the intervention(s) focused on perinatal transmission contexts [e.g., 9], or if they utilized time-series-only designs [e.g., 10]. Consistent with these criteria, studies that did not clearly focus on sexual risk reduction were excluded. Several RCTs with HIV+ participants were excluded because (1) they did not provide critical statistics necessary for the meta-analysis [e.g., 11], (2) did not have a sexual risk-reduction component [e.g., 12], or (3) did not report either condom use or number of partners [e.g., 13]. For example, although Coates et al.’s [12] study targeted HIV+ individuals, its intervention focused on coping and made no mention of sexual risk reduction. Studies with samples of both HIV− and HIV+ participants were included if the number of HIV+ participants was ≥30, and if separate effect sizes could be calculated for the HIV+ participants. If the latter were not available in the original reports, we contacted the authors of such studies and requested separate analyses for the HIV+ individuals in their sample; these requests resulted in 4 reports that are not typically known to the literature on prevention with seropositives [14,15,16,17]. Inclusion of these results allowed comparison of whether efforts focused on HIV+ individuals differ from those focused on HIV− or individuals whose HIV serostatus was unknown.

These criteria yielded 15 studies (Figure 1). At the first follow-up, 3,234 HIV+ individuals participated, reflecting a retention rate of 79%. Consistent with meta-analytic convention [1,18], each intervention was treated as an individual study during analysis.

Figure 1.

Selection process of study inclusion in the meta-analysis

Study Information

Two raters independently coded the qualitative content of each study to describe the studies and to determine whether variation in ESs could be attributed to features of the studies. Studies were coded for the following dimensions: (1) sample characteristics (e.g., ethnicity, gender, sexual orientation); (2) risk characteristics (e.g., sex trade, drug use, proportion of entire sample HIV+); (3) design and measurement specifics (e.g., number of follow-ups); and (4) content of control and intervention condition(s) (e.g., number of sessions, training of session leaders). Because leading HIV prevention experts recognize the importance of developing interventions based upon a conceptual model of risk behavior [19], we also coded studies according to whether they provide information, motivational, and/or behavioral skills components, consistent with a leading meta-theoretical model of HIV risk behavior [20].

Across all study- and intervention-level categorical dimensions, coders agreed on 60% to 100% of judgments. Categorical variables that were used only for descriptive purposes and were not included as explanatory variables in the current analyses were coded with 90% agreement and average values of .84. Variables that served as explanatory variables were coded with 93% agreement and average values of .86. Disagreements were resolved through discussion.

Effect Size Derivation

We calculated individual ESs for relevant measures reported in each of the separate interventions. Specifically, we analyzed two self-reported sexual outcomes: (1) condom use (unspecified, vaginal, anal, oral) and (2) number of partners. Because results from the four condom use varieties converged closely, effect sizes were averaged for the primary analyses of condom use. For the purpose of this review, condom use was inferred from any measure that implied it (e.g., unprotected acts). Studies nearly always defined outcomes in continuous rather than dichotomous terms; thus, the ES calculated was the standardized mean difference (d). The pooled standard deviation served as the denominator in the ES calculation; in a small minority of cases, the denominator was instead another form of standard deviation (e.g., the standard deviation of the paired comparisons) because the pooled standard deviation was unavailable and could not be calculated from the report. The sign of each effect size was set so that it was positive when the outcome favored risk reduction, and effect sizes were corrected for sample size bias [21]. One report offered intervention statistics separately by gender [7] and another by ethnicity [14]; these reports were treated as individual studies. Effect sizes were calculated on the measures provided at the first follow-up after the intervention to reduce method variance across studies. We averaged the ESs from multiple measures of the same outcome. When two or more intervals were assessed (e.g., condom use in previous week vs. previous 30 days), we used the the interval that most closely matched the time since the intervention ended.

When a study offered a statistic controlling for baseline differences as well as statistics that were not adjusted, we used the former. If a statistic did not control for baseline, but baseline results were reported, Becker’s [22] strategy was employed wherein the post-intervention effect size is corrected for any differences between the groups at baseline. When studies reported odds ratios, we transformed them to d using the Cox transformation according to published guidelines [23]. Analyses were performed with both fixed- and random-effects assumptions; analyses to examine whether features of the studies explained variability in the effect sizes followed fixed-effects assumptions [24,25]. Because at least one of the fixed-effects models of study features fully explained the variability in condom use effects, there was no need to incorporate random-effects assumptions in analyses.

RESULTS

Description of Studies

Table 1 lists the studies and their main descriptive features. The studies in the sample appeared between 1993 and 2004. Eleven studies included only HIV+ individuals, whereas the remaining four studies focused on HIV− individuals but also included some participants who were HIV+ (M = 14% HIV+ participants in these 4 samples). The samples in the studies were primarily male (64%), of African-American background (49%), and averaged 35 years of age. Fourteen (93%) studies were conducted in the U.S., with the majority (73%) of these conducted in medium to large cities. Only two studies sampled those who were known to engage in sex trading or commercial sex work (13%), and only one sampled HIV+ persons who were in drug treatment (7%); no study included incarcerated samples. More frequently, studies sampled populations of men who have sex with men (MSM; 7 [47%]) and those who use recreational drugs (12 [80%]).

Table 1.

Descriptive Features of Studies in Sample.

Study	Sample	Setting & Location	Intervention(s), Focus, Duration	Time to Follow-up	Outcomes Measured
Cleary et al. [7]	271 Blood donors	Blood center, New York, NY	Structured Intervention Program† (6 weeks)	46 weeks	Proportion sexually active
	100% HIV+		HIV/AIDS information		Condom use for vaginal sex, vaginal sex during menses, anal receptive and active sex, and oral sex
	78% Men		Focus on sexual risk reduction		Oral-anal sex
	5% MSM
	45% White
	31% Black
	23% Hispanic
Dushay et al. [14]	1300 Drug users*	Community outreach centers; Hartford, CT	African-American Culturally Competent	20 weeks	Number of sexual partners and IDU sex partners
	17% HIV+		Enhanced Intervention (3 weeks)
	73% Men		HIV/AIDS information
	50% Black		Motivation
	50% Hispanic		Behavioral skills
			Equal focus on sexual and drug risk reduction
			Puerto Rican Culturally Competent Enhanced
			Intervention (3 weeks)
			HIV/AIDS information
			Motivation
			Behavioral skills
			Equal focus on sexual and drug risk reduction
El-bassel et al. [15]; Witte [35]‡	217 Heterosexual couples*	Primary health care setting: New York, NY	Couples Relationship-Based Intervention (6 weeks)	13 weeks	Frequency unprotected sex acts
	21% HIV+		HIV/AIDS information		Proportion protected sex acts
	55% Black		Motivation		Number of sexual partners
	39% Hispanic		Behavioral Skills
			Focus on sexual risk reduction
			Woman-Alone Relationship-Based Intervention (6 weeks)
			HIV/AIDS information
			Motivation
			Behavioral skills
			Focus on sexual risk reduction
Fogarty et al. [36]; Gielen et al. [37]‡	322 Women	Outpatient and pediatric HIV clinics & a primary HIV care facility: Baltimore, MD	Enhanced Intervention (26 weeks)	Immediately	Condom use with main male sex partner
	100% HIV+		HIV/AIDS information
	43% Involved in sex trading		Behavioral skills
	6% White		Focus on sexual risk reduction
	91% Black
	1% Hispanic
Kalichman et al. [38]	328 patients seeking HIV/AIDS care	Study clinic: Atlanta, GA	Transmission Risk-Reduction Intervention (2.5 weeks)	13 weeks	Number of sexual partners
	100% HIV+		HIV/AIDS information		Frequency of intercourse and unprotected sexual acts
	70% Men		Motivation		Condom use
	22% White		Behavioral skills
	74% Black		Focus on sexual risk reduction
Kelly et al. [39]	115 Depressed men	Mental health study clinic: Milwaukee, WI	Cognitive-Behavioral Group Intervention (8 weeks)	13 weeks	Instances and number of participants reporting unprotected insertive & receptive anal intercourse
	100% HIV+		HIV/AIDS information
	94% MSM		Focus on sexual risk reduction
	62% White		Social Support Group Intervention (8 weeks)
	29% Black		HIV/AIDS information
			Focus on sexual risk reduction
MacNeil et al. [40]	154 newly diagnosed HIV+ individuals	Counseling center or homes of participants: Semi-urban Tanzania, Africa	Enhanced Care and Support Intervention (13 weeks)	13 weeks	Disclosed serostatus to sexual partner
	100% HIV+		HIV/AIDS information		Condom use for last sexual intercourse
	66% Women		Focus on sexual risk reduction		Sex with person other than spouse/main partner
	100% Black
Margolin et al. [41]	90 IDU patients in drug treatment	Inner-city methadone maintenance program: New Haven, CT	HIV+ Harm Reduction Program (26)	Immediately	Unprotected penetrative sex
	100% HIV+		HIV/AIDS information
	70% Men		Motivation
	36% White		Behavioral skills
	49% Black		Equal focus on sexual and drug risk reduction
	16% Hispanic
NIMH [16]	3706 STD clinic patients*	Inner city, community based clinics: New York, NY; Northern NJ; Baltimore, MD; Atlanta, GA; Milwaukee, WI; Los Angeles, Orange, San Bernardino counties, CA	Small-Group HIV Risk Reduction Program (3 weeks)	9 weeks	Frequency of unprotected vaginal or anal intercourse
	2.5% HIV+		HIV/AIDS information		Proportion of condom use
	58% Women		Motivation		Consistent condom use or abstinence
	74% Black		Behavioral skills
	25% Hispanic		Focus on sexual risk reduction
Richardson et al. [42]	886 sexually active patients seeking HIV treatment	HIV clinics: CA	Gain-Framed Safer-Sex Intervention (45 weeks)	Less than 30 weeks	Unprotected insertive or receptive anal or vaginal intercourse
	100% HIV+		HIV/AIDS information
	74% MSM		Focus on sexual risk reduction
	86% Men		Loss-Framed Safer-Sex Intervention (45 weeks)
	41% White		HIV/AIDS information
	16% Black		Focus on sexual risk reduction
	37%  Hispanic
	82% HAART
Roffman et al. [17]	548 Gay & Bisexual Men*	Telephone intervention: U.S., Puerto Rico, and Canada	Cognitive-Behavioral Group Counseling Intervention (14 weeks)	Immediately	Unprotected anal and oral intercourse
	14% HIV+				Proportion of all anal and oral events unprotected
	100% MSM		HIV/AIDS information
	84% White		Motivation
	7% Black		Focus on sexual risk reduction
	9% Latino
Rotheram-Borus et al. [8]	310 HIV+ youths, ages12–24	Adolescent clinic care sites:	“Stay healthy” and “Act Safe” Intervention (26 weeks)	13 weeks	Number of sexual partners
	100% HIV+	Los Angeles CA;	HIV/AIDS information		Unprotected sex acts
	72% Men	San Francisco, CA;	Motivation		No sexual risk pattern
	19% White	New York, NY;	Behavioral skills
	27% Black	Miami, FL	Equal focus on sexual and drug risk reduction
	37% Hispanic
Rotheram-Borus et al. [43]	151 HIV+ youths, ages16–29	Community agencies:	Telephone Intervention (18 weeks)	47 weeks	Number of HIV− partners
	100% HIV+	Los Angeles, CA;	HIV/AIDS information		Protected sex acts with all partners, HIV− partners
	69% MSM	San Francisco, CA;	Motivation		100% condom use or abstinence
	78% Men	New York, NY	Behavioral skills
	23% White		Equal focus on sexual and drug risk reduction
	26% Black		In-Person Intervention (18 weeks)
	42% Hispanic		HIV/AIDS information
	50% HAART		Motivation
			Behavioral skills
			Equal focus on sexual and drug risk reduction
Wingood et al. [44]	366 Women	HIV/AIDS clinics and health departments: Anniston, AL; Birmingham, AL ; Montgomery, AL; Atlanta, GA	“Women Involved in Life Learning from Other	22 weeks	Frequency of unprotected vaginal sex
	100% HIV+		Women” (WiLLOW) (4 weeks)		Proportion who have never used condoms
	84% Black		HIV/AIDS information
			Motivation
			Behavioral skills
			Focus on sexual risk reduction
Wolitski et al. [30];	730 HIV+ MSM	Community settings: New York, NY; San Francisco, CA	Seropositive Urban Men’s Intervention Trial (SUMIT) (6 weeks)	13 weeks	Unprotected anal and oral intercourse with HIV− or unknown-status partners
Wolitski et al. [45]	100% HIV+		HIV/AIDS information
	51% White		Motivation
	23% Black		Focus on sexual risk reduction
	17% Latino
	1% Asian

Abbreviations: HAART, highly active antiretroviral therapy; IDU, injection drug user; MSM, Men who have sex with men; STD, sexually transmitted disease.

^*Sample characteristics reported describe a mixed sample of both HIV-seropositive and -seronegative or -unknown participants.

^†Intervention was administered to both men and women, but results were stratified into samples of men only and women only; this single intervention was treated as two separate interventions for our current analyses.

^‡Two reports of one study were available and were used to code the study features or to calculate effect sizes.

All studies used random assignment, with the majority of studies (14 [93%]) assigning individuals (rather than intact groups) to conditions. All studies utilized a pre- and post-test design and included an average of 2.3 (SD=1.0) follow-ups after baseline data collection. The initial follow-up, the focus of this synthesis, occurred at a mean of 19.00 weeks post-intervention (range, 0–47 weeks). Only 3 studies took measures immediately and their interventions averaged 22.00 weeks in length; the other studies interventions lasted an average of 11.71 weeks. All interventions provided participants with HIV/AIDS information. Thirteen (65%) provided motivational components (e.g., social support) and 12 (60%) provided behavioral skills training (e.g., for condom use). Interventions included an average of five participants who met for six sessions that averaged 98 minutes each. Controls were typically either a wait-list (8 [40%]) or an HIV/AIDS education comparison (7 [35%]). The latter were typically matched for time/contact, or provided an abbreviated form of the intervention condition; they averaged five participants who met for three sessions of 77 minutes each.

Efficacy of the Interventions

Fourteen interventions were evaluated using only condom use, two interventions were evaluated using only number of partners, and five used both measures. ESs for studies that reported both measures were highly correlated, r = .73. Across the 19 interventions that assessed condom use, interventions increased condom use relative to controls, d. = 0.16, 95% CI 0.08 to 0.25. (Table 2) Yet, the effect sizes varied widely around this mean value, Q(18) = 55.15, P < .001. (Figure 2) An examination of intervention efficacy within the four types of condom measures (unspecified, vaginal, anal, oral) confirmed this overall result. These results were parallel using either fixed- or random-effects assumptions. Seven of the studies assessed the number of sexual partners; relative to controls, intervention participants did not decrease the numbers of partners they reported, d. = −0.01, 95% CI −0.16 to 0.14. These effects were homogeneous, Q(6) = 4.62, P = .593. (Table 2)

Table 2.

Efficacy of interventions to promote risk reduction at studies’ first follow-up assessments.

		Weighted mean d (and 95% confidence interval)		Homogeneity of effect sizes
Outcome	k of interventions	Fixed effects	Random effects	Q	P
Condom use
Unspecified context	15	0.16 (0.08, 0.25)	0.16 (−0.05, 0.37)	80.76	<.0001
Vaginal	3	0.37 (0.20, 0.54)	0.45 (0.14, 0.77)	5.02	.081
Anal	5	0.21 (0.09, 0.33)	0.24 (0.04, 0.45)	7.97	.158
Oral	5	0.15 (0.03, 0.26)	0.16 (0.01, 0.30)	5.31	.257
Averaged	19	0.16 (0.09, 0.23)	0.19 (0.05, 0.33)	55.15	<.0001
Number of sexual partners	7	−0.01 (−0.16, 0.14)	−0.01 (−0.16, 0.14)	4.62	.593

Figure 2.

Forest plots of effect sizes for interventions that assessed condom use (top, A) or number of partners (bottom, B). The delta symbol for each effect size is sized proportionally to its weight in the analyses. The confidence interval for each effect size is indicated by its line and for the mean by the width of its diamond. Zero values indicate exactly no difference between the two groups. Effect sizes that significantly favor the intervention appear in green (right side); those that favor the control group appear in red (left side).

Intervention Features Associated with Increased Condom Use

Analyses revealed three features of the studies that were associated with smaller or larger efficacy as gauged by condom use. (Table 3) First, interventions were more successful to the extent that they sampled younger rather than older participants. Second, interventions were more successful to the extent that MSM were not included in the sample; interventions with 100% MSM exhibited no significant change. Third, interventions that included both motivational and behavioral-skills components increased condom use compared to interventions that had only one of these components, or neither; unless informational, motivational and behavioral-skills components were included, interventions had no effect on condom use. Model fit was excellent in the case of the MSM model, Q_Residual(10) = 12.16, P = .27, but not as good for each of the age and intervention content models. It is worth noting that no study focused on MSM included all three of the content components.

Table 3.

Features of studies that were linked to the efficacy of interventions to increase condom use.

	Patterns		Test statistics
Study dimension	Level	Mean d (95% CI)	k	Statistic	P
Age of sample	20 years	0.53 (0.22, 0.84)	14	β=−0.35	.018
	40 years	0.11 (0.02, 0.20)
Proportion of sample MSM	All MSM	0.04 (−0.07, 0.15)	12	β=−0.66	.002
	No MSM	0.42 (0.24, 0.60)
Inclusion of intervention elements	Only information	0.05 (−0.07, 0.16)	7	QB(2)=10.98	.004
	Information plus either motivational or behavioral skills	0.12 (−0.02, 0.26)	3
	All three dimensions	0.32 (0.20, 0.43)	9

Note. Analyses are based on fixed-effects assumptions; each effect size (d) was weighted by the inverse of its variance. Analyses were not undertaken on the sexual frequency outcomes. MSM = Men who have sex with men. CI = confidence interval. k = number of studies. P = probability. Q_B = Homogeneity between categories; when statistically significant, implies differences among the means for the observed levels.

We also evaluated whether studies that focused exclusively on HIV+ individuals achieved greater efficacy than those that included individuals with unknown or negative serostatus; a comparison revealed no significant difference. Similarly, none of the patterns reported in the preceding paragraph changed when analyses were restricted to samples of 100% HIV+ individuals. The following features of the studies also did not relate to the magnitude of condom use effect sizes: Gender, racial composition, knowledge of serostatus, year of study, whether or not the intervention was designed to focus on HIV+ individuals, whether or not participants were injection drug users, attrition, and time since intervention ended.

Given the relatively brief follow-up intervals, and because decay of intervention effects is an important consideration, an exploratory analysis included the additional condom use follow-up measurements that five studies provided. This analysis, also, showed no change in intervention efficacy over time, β = 0.01, P = .93. Finally, there was no tendency for the effect sizes to depend on the year in which the interventions were conducted, β = −0.20, P = 0.14.

COMMENT

This quantitative synthesis is the first to evaluate the extent to which interventions evaluated with people who live with HIV work to reduce sexual risk behavior. This review focused on condom use and number of partners because these measures are the most commonly used markers of risk behavior. We synthesized RCTs because such studies provide the strongest evidence regarding the efficacy of HIV risk reduction programs. In total, 15 RCTs and 21 interventions qualified for the review (Table 1). Results showed that, with only some exceptions noted below, interventions led to reduced sexual risk behavior in people living with HIV as gauged by condom use (Table 2), an effect that showed no tendency to decay with time. The magnitude of this risk-reduction effect is equivalent to, or larger than, the effects reported in earlier meta-analyses of HIV prevention trials conducted in HIV− samples [e.g., 1,18,26–29], whose mean ESs range from 0.06 [26] to 0.25 [27].

The tendency for interventions to increase condom use relative to controls depended to some extent on the features of the studies. Compared to controls, intervention group members’ condom use improved to the extent that samples had fewer men who have sex with men (MSM), in younger samples, and, importantly, when interventions included motivational and behavioral skills enhancements. (Table 3) Although the overall magnitude of the effect size on condom use was small, it was larger for interventions that included both motivational and skills enhancements, for those that had younger participants, and for those that did not sample MSM. Indeed, interventions had no significant impact when the sample was 100% MSM or when motivational and behavioral skills enhancements were omitted.

Only seven studies examined number of sexual partners as an outcome; these studies revealed no change for intervention members compared to control–group members. This non-significant effect may reflect a restricted range (i.e., floor effect) on this variable, reliance on condom use as a risk reduction strategy, lack of intervention efficacy on this variable, or other factors not addressed in our analyses. Another possibility is that those who test positive for HIV avoid HIV-negative partners and prefer HIV-positive partners, a strategy known as serosorting [2,30,31,32]. Unfortunately, too few studies did reported partner data in a manner that would permit such an analysis. One of the studies in our sample, which addressed MSM [33] examined just this possibility and found a small but non-significant trend for intervention participants to be less likely to have unprotected intercourse with HIV–negative or HIV–unknown partners. Future research should continue address this important issue.

Previous meta-analyses suggested that individuals who test positive for HIV increase risk-reduction behaviors such as condom use [1], especially with serodiscordant partners. As mentioned, interventions for MSM did not reduce sexual risk behavior compared to control interventions, a pattern that differs from that reached in an earlier meta-analysis of studies with (presumably) HIV− MSM [28]. Yet, because no study in the current meta-analysis provided motivational and behavioral skills to a sample of MSM, it is not presently possible to know whether such enhancements would prove successful with HIV+ MSM. However, a recent review of the literature examining risk reduction for all MSM [45] strongly suggested that notable risk reduction can occur, especially when interventions have a strong skills training component, a conclusion that converges with the current review’s findings. Yet their review did not examine the extent to which serostatus related to success. Future research should test whether more comprehensive risk reduction programs (i.e., those with information, skills, and motivational components) results in improved results with HIV+ MSM.

The age-related results in the current analyses were unexpected. Contrary to earlier reviews, we found that interventions were more efficacious with younger rather than older samples [e.g., 18, 27–29]. We hypothesize that older samples may have had longer duration partnerships than for those in the younger samples, a factor that is known to increase resistance to change [42]. Future studies should investigate this hypothesis.

Perhaps the most surprising finding of this work is that more than two decades into the epidemic, there have been so few intervention RCTs that focus on people living with HIV. We located only 15 RCTs that addressed the needs of this important population. Of this number, only 11 were explicitly designed to address risk behaviors in HIV+ persons. Although there have been literally hundreds of studies conducted with uninfected populations, the relative paucity of controlled studies with infected persons indicates the urgent need for research in this area, as recognized by the Centers for Disease Control and Prevention when they launched “Advancing HIV Prevention: New Strategies for a Changing Epidemic.” This initiative encourages early diagnosis of HIV, increased access for HIV care, and most important to the current context, strengthened HIV prevention services for HIV+ persons.