Descriptive information about included trials is reported in Tables 1, 2, and 3. The 37 included studies enrolled n = 12 629 participants at baseline. Participants were primarily from the United States (k = 34; n = 12 047), with additional trials taking place in Australia,⁵⁰ China,⁵⁵ and Iran.⁴⁴ Two trials did not report participant ages, but across the remaining trials, mean participant ages ranged from 25 to 41 years, with a median of 34.5 years. Trials often enrolled single-gender samples: there were 9 trials among men, 12 among women, and 16 among mixed samples (median = 72% male). Across the 32 US trials reporting ethnicity, participant samples were primarily White (≥ 67%) in 6 trials, primarily of non-White race/ethnicity (≤ 33% White) in 14 trials, and mixed in the remaining 12 trials. Trials enrolled participants with a range of criminal justice involvement; at the time the intervention began, participants were incarcerated in residential correctional facilities (k = 19; n = 6329); staying in court-ordered inpatient drug treatment facilities (k = 2; n = 217); in a jail diversion program (k = 1; n = 15); on probation, parole, or work-release (k = 8; n = 3336); or in the community with a mix of supervisory arrangements ranging from parole to no supervision (k = 7; n = 2732). Nine studies provided information about the types of crimes leading to participants’ criminal justice involvement: these typically included arrests because of drug crimes, property crimes, and prostitution.

TABLE 1— Participants, Intervention Characteristics, and Retention of Included Studies Evaluating Psychosocial Interventions in a Systematic Review of HIV Risk-Reduction Interventions in Incarceration and Community Settings

TABLE 2— Participants, Intervention Characteristics, and Retention of Included Studies Evaluating Opioid Substitution Therapy Interventions in a Systematic Review of HIV Risk-Reduction Interventions in Incarceration and Community Settings

TABLE 3— Participants, Intervention Characteristics, and Retention of Included Studies Evaluating HIV Testing Interventions in a Systematic Review of HIV Risk-Reduction Interventions in Incarceration and Community Settings

Where reported, the median percentage of participants across studies with a high-school diploma or general equivalency diploma was 54% (k = 20); when studies reported average number of years of education, the median across studies was 11.2 (k = 12). Same-sex sexual orientation or behavior was discussed in only 2 studies,^72,73 which reported small percentages of participants disclosing same-sex sexual behavior or a same-gender primary partner; another study limited enrollment to individuals reporting heterosexual intercourse,⁴⁸ and 34 studies did not discuss sexual orientation. Inclusion criteria for enrollment in 23 of the 37 studies required recent substance use or a measure of drug or alcohol dependence (n = 7355). Twenty studies compensated participants for completing assessments or study activities, typically around $10 to $20 for baseline assessments and $25 to $50 for follow-up assessments. Typical recruitment procedures in incarceration facilities included mailings and in-person outreach to incarcerated individuals at the time of intake or a preset time before release; recruitment in community settings included mailings and in-person outreach at times of arrest, release from incarceration, probation visits, or drug court visits.

Interventions varied widely across trials. Seven studies assessed OST for drug treatment (n = 967),^{44,46,49,50,58,62,67} sometimes paired with psychosocial intervention, with the dual goals of reducing both substance use and associated HIV risk behaviors. These trials included 4 studies of methadone maintenance treatment (MMT), 1 study of buprenorphine maintenance, 1 comparing MMT to buprenorphine maintenance, and 1 comparing MMT to buprenorphine and naloxone (Suboxone) maintenance.

Twenty-seven studies assessed psychosocial strategies for preventing HIV (n = 10 344),^{33,42,43,44,47,48,51–55,59–61,63–66,68–73} of which 18 also aimed to reduce drug or alcohol use along with HIV risk. Fifteen of the 27 psychosocial intervention studies declared a theoretical basis for the intervention, which most frequently included motivational interviewing, the health belief model, social cognitive theory, and the transtheoretical model. The psychosocial strategies used a group format (k = 5), an individual format (k = 16), or both group and individual activities (k = 3); 2 trials compared group interventions against individual modalities, and 1 did not state a format. Seven interventions included at least 1 peer-led component, and 4 trials included an active treatment arm that was primarily media-based (computer or video intervention); 6 trials evaluated a form of case management. Dosage of psychosocial interventions ranged from a single 20-minute session to 6 full months of a therapeutic community environment; across trials, the median intervention length was 9 hours.

Finally, 3 trials tested the effect of varying the time or place of offering participants an HIV test, with the goal of optimizing HIV testing behavior.^8,56,57

Twenty-two of the 37 trials reported at least 1 method for assessing or increasing fidelity of intervention implementation, such as facilitator training and supervision, standardized intervention materials or manuals, attendance logs, fidelity checklists, or review of taped sessions.

Control groups also varied across studies and included no treatment (k = 3), usual care (which could include a range of services varying by local conditions; k = 7), basic information about HIV (k = 6), a diluted or less-intense (“nonenhanced”) version of the active treatment (k = 8), an attention-matched control (i.e., identical in dosage and format to the intervention, but focusing on another topic instead of HIV; k = 1), a placebo for 1 OST trial (k = 1), and another active intervention intended to prevent HIV (k = 11).

Information about methodological quality was underreported (Tables 4, 5, and 6). Thirty-one studies were randomized controlled trials, of which 11 reported the method of randomization (usually a computer-generated randomized sequence). The 6 quasi-randomized controlled trials “randomized” participants by alternation, assignment by month, or coin flip. Nine studies reported strategies for concealing the allocation sequence from staff responsible for recruitment and enrollment. Analyses were generally conducted on a complete case basis, in which participants are analyzed in original assignment groups but without imputing missing data for dropouts (k = 28).¹⁰⁷ Four studies conducted per-protocol analyses that excluded or reassigned participants who deviated from the intended interventions, and 4 studies employed full intention-to-treat analyses that accounted for dropouts (or had no attrition).¹⁰⁷ The unit of randomization was almost always the individual; in the 3 trials that randomized clusters of participants (by time block or facility), analytic methods for controlling for clustering were not described. Of the 32 studies that commented on baseline equivalence, 13 found group differences at baseline, and 6 of these explicitly described controlling for baseline differences in analyses. With the exception of 1 placebo-controlled trial, no study described methods for blinding participants or personnel to condition. Twenty-eight studies did not describe (or did not use) methods for blinding outcome assessors to reduce risk of detection bias. The longest follow-up ranged from immediate to 14.5 months after baseline, with a median longest follow-up time of 6 months across studies. Median retention across studies was 77% at longest follow-up; 23 studies commented on sources or effects of attrition. Only 5 studies presented a power calculation justifying sample size.

TABLE 4— Methodological Characteristics of Included Studies Evaluating Psychosocial Interventions in a Systematic Review of HIV Risk-Reduction Interventions in Incarceration and Community Settings

TABLE 5— Methodological Characteristics of Included Studies Evaluating Opioid Substitution Therapy Interventions in a Systematic Review of HIV Risk-Reduction Interventions in Incarceration and Community Settings

TABLE 6— Methodological Characteristics of Included Studies Evaluating HIV Testing Interventions in a Systematic Review of HIV Risk-Reduction Interventions in Incarceration and Community Settings

Twenty-two of the 37 studies reported using a biological measure at baseline or any follow-up, most commonly urine testing for drug use (k = 12), hair testing for drug use (n = 2), unspecified testing for morphine (k = 1), a cervical swab for STIs (k = 1), oral testing for HIV (k = 1), and blood testing for HIV, hepatitis C, and other STIs (k = 5). Despite the fact that at least 6 studies conducted STI testing, however, only 4 studies reported HIV or STI incidence outcomes. Thirty-two studies assessed sexual or IDU behaviors; of those reporting methods of assessment, 2 studies used audio computer-assisted self-interviewing (ACASI), 5 used written questionnaires, and 23 used interviewer-administered questionnaires. Four studies did not report a sexual or IDU behavior, but assessed the proportion of participants who accepted HIV testing according to direct observation or medical records. Self-report measures of sexual behavior, IDU behavior, drug use, and recidivism varied and often appeared to be developed for individual studies, although several used assessments such as the Texas Christian University HIV/AIDS Risk Assessment, the HIV Risk-Taking Behavior Scale, the Criminal Justice Drug Abuse Treatment Studies intake form, the Timeline Followback approach for assessing substance use, and the National Institute on Drug Abuse Risk Behavior Assessment questionnaire; look-back periods for behavioral outcomes ranged from 14 days to 12 months, but typically were 1 to 3 months.

Three studies reported HIV infection outcomes, all at short-term follow-up (n = 456).^41,50,55 All findings were nonsignificant with control groups including usual care,⁵⁵ no treatment or waitlist,⁵⁰ and information only.⁴² Two studies reported a measure of STI (n = 285),^48,50 including hepatitis C virus incidence⁵⁰ and time until a positive STI test,⁴⁸ and both used no-treatment or waitlist controls. Group differences in STI measures were nonsignificant in both studies at short-, medium-, and long-term follow-up.

Seventeen studies reported a measure of condomless sexual intercourse at any follow-up (n = 5219).^{42,47,55,58–60,63–65,68–73} Three studies (n = 1161) reported significant group differences favoring a peer-designed DVD intervention over a standard video at short- and medium-term follow-up,⁶⁴ favoring motivational interventions focusing on HIV or HIV plus intimate partner violence over standard counseling and testing at short- and medium-term follow-up,⁷² and favoring a multisession individualized intervention over a single-session control.⁷³ One study identified a significant difference in the opposite direction at long-term follow-up (n = 511),⁶⁸ showing that women released from jail who received case management services after jail-based empowerment groups reported a significantly higher frequency of recent condomless sexual intercourse compared with participants who attended the empowerment groups without case management.

Eleven studies reported a measure of number of sexual partners (n = 3211).^{33,42,43,47,52,58,59,63,68} Only 1 study found a significant group difference (n = 94) at long-term follow-up, favoring the addition of a “well-woman” checkup and peer-led intervention to a testing and counseling intervention for women recruited from drug courts.⁴⁷

Nine studies reported a measure of condom use (n ≤ 1220).^{33,42–44,52,54,55,61} Three studies reported evidence of a significant intervention benefit, all at short-term follow-up (n = 228). These results favored the addition of behavior skills training to a standard educational intervention for women court-ordered to drug treatment,⁵² favored a peer-led intervention over usual care for incarcerated men,⁵⁴ and favored individual and small-group HIV education over an attention-matched control for adult probationers.⁶¹

Eight studies reported results by using a composite index of sexual risk behavior (n = 1185).^{43,45,46,51,52,62,66,70} Of these, 2 found a significant intervention benefit at any follow-up (n = 131). One trial among incarcerated men found that an educational intervention led by an HIV-negative peer was significantly more beneficial than usual care at short-term follow-up.⁴⁵ The other trial was a pilot study enrolling n = 15 individuals from a jail diversion program: participants who received MMT or combination buprenorphine and naloxone at a specialist treatment facility for opioid-dependent individuals reported significantly safer behaviors at medium-term follow-up than participants who received buprenorphine and naloxone in a primary care setting.⁴⁶

Six studies reported a measure of all sexual activity (compared with sexual abstinence; n ≤ 961).^{42,44,50,54,55,58} No study found a significant difference between experimental conditions at any time point, using a range of control groups that included information, usual care, no treatment, or an alternative HIV prevention intervention.

Six studies reported a measure of engagement in transactional sexual intercourse (n = 1637).^{47,55,63,68,70} Of these, only one found a significant benefit,⁷⁰ showing that incarcerated women randomized to take part in a therapeutic community intervention for 6 months were less likely than participants in outpatient treatment to report having sexual intercourse in exchange for money or drugs at medium-term follow-up (n = 314). By contrast, 1 intervention found a significant iatrogenic effect at long-term follow-up (n = 511),⁶⁸ finding that female jail releasees who received case management services and attended jail-based empowerment groups were more likely to report having sexual intercourse in exchange for money or drugs compared with controls who did not receive case management.

Five studies reported any measure of sexual intercourse under the influence of drugs or alcohol (n = 1289).^42,58,60,68 One reported a significant intervention benefit at medium-term follow-up (n = 329),⁶⁰ favoring case management using the Treatment Alternative to Street Crime model over alternative case management for drug-using probationers and parolees who reported a high baseline frequency of recent sexual intercourse under the influence. One trial reported a significant iatrogenic effect at long-term follow-up (n = 511),⁶⁸ finding a higher frequency of recent sexual intercourse under the influence among female jail releasees who attended empowerment groups along with receiving case management, compared with controls who solely attended the empowerment groups.

Seventeen studies reported a measure of self-reported incidence or frequency of IDU at any follow-up (n ≤ 4173).^{33,42–44,49,50,54,55,58,63,65–67,70,71,73} Of these, 3 studies found evidence of significant intervention benefit (n = 835); 2 of these were trials of MMT for incarcerated men. In one trial, men who received MMT reported a lower incidence and frequency of heroin and other drug injection at short-term follow-up compared with waitlist controls⁵⁰; in the other trial, men receiving MMT also reported a lower incidence of IDU at medium-term follow-up compared with controls who received alternatives to MMT.⁴⁴ The third trial found that participants who received 6 months of case management after arrest were less likely to report IDU compared with controls who viewed an educational video, as well as participants who viewed the video and received a single counseling session, but effects were not sustained at medium-term follow-up.³³ Too few events occurred for meaningful analyses in 2 studies.^42,73

Twelve studies reported a measure of self-reported needle sharing or use of sterile injection equipment (n ≤ 2605).^{33,42–44,50,54,55,58,61,62,72} Of these, 4 found a significant group difference at any time point (n = 1005). Three of these also reported significant benefits for incidence and frequency of IDU, described previously.^33,44,50 The 2 trials of MMT for incarcerated men found that MMT recipients were less likely to report sharing IDU equipment at short-term follow-up compared with waitlist controls,⁵⁰ and were less likely to report sharing IDU equipment at medium-term follow-up compared with controls who received other forms of drug treatment.⁴⁴ The trial of case management found that participants who received case management were less likely than educational video recipients to share needles, even when the video viewers also received a single counseling session; also, among those who did share needles, case management recipients were more likely to clean needles before use than those who received the video without counseling.³³ Similar to the results for the frequency of IDU, these effects were not sustained beyond short-term follow-up. The fourth study found that incarcerated participants who received HIV education and risk assessment reported sharing fewer types of drug use equipment than no-treatment controls.⁴³ Too few events occurred for meaningful analysis in 1 study.⁴²

Six studies (n = 1770) assessed interventions aiming to increase HIV testing behavior.^{8,42,53,56,57,61} Four found significant differences at short-term follow-up (n = 1481), favoring a computer-based intervention over written information,⁴² on-site testing at probation offices over off-site referrals,⁸ offering immediate or next-day testing over 1-week postponed testing for men entering jail,⁵⁷ and offering next-day testing over immediate or 1-week postponed testing for women entering jail.⁵⁶

Twenty-four studies reported an assessment of drug use at any follow-up (n ≤ 5874),^{33,44–47,49,50,52,54,55,58,60,62,63,65–71} including all 7 trials that tested OST strategies. Drug use data were derived from biological testing alone in 3 studies^44,49,55 self-report alone in 17 studies,^{33,45–47,52,54,60,62,63,66,67,69–71} and both types of measures in 4 studies.^50,58,65,68 Ten studies found a significantly favorable intervention effect at any time point (n = 1975), including 3 studies with a favorable intervention effect for a biological outcome assessment (n = 249).^44,49,58 Programs showing benefit included 5 OST interventions, demonstrating evidence for MMT compared with waitlist controls at short-term follow-up,⁵⁰ MMT compared with non-MMT treatment alternatives at medium-term follow-up^44,58 and long-term follow-up,⁵⁸ prerelease MMT compared with a postrelease MMT referral at medium- and long-term follow-up,⁵⁸ postrelease MMT referral compared with controls receiving no referral at medium-term follow-up,⁵⁸ buprenorphine compared with placebo at short-term follow-up,⁴⁹ and prerelease MMT compared with postrelease referrals to funded community treatment.⁶⁷

The other 5 trials with significant evidence of treatment benefit tested psychosocial interventions. One trial found significant benefit for an educational intervention led by HIV-positive peers compared with usual care at short-term follow-up.⁴⁵ The results of another trial favored peer education and “well woman” checkups compared with HIV testing alone at long-term follow-up.⁴⁷ Findings of a third trial favored case management using the Treatment Alternatives to Street Crime model compared with other case management services at medium-term follow-up, but only among probationers and parolees who reported using a larger number of drugs at baseline.⁶⁰ A fourth trial found significant benefit for participation in a 6-month prerelease therapeutic community compared with outpatient treatment at medium- and long-term follow-up.⁷⁰ The final trial found a benefit of case management services at short-term follow-up compared with a single-session counseling session with a video, and compared with viewing the video alone.³³ In contrast to these studies, 1 study found a significant iatrogenic effect (n = 90): among participants who agreed to urine testing for drug use, parolees in Assertive Community Treatment case management were more likely to test positive than usual care controls.⁶⁵

Eleven studies measured reincarceration at any follow-up (n = 3687),^{33,50,58,62,65,67,68,70,71,73} of which 6 reported using a data source other than self-report (e.g., state records, study records of whether follow-up interviews took place in correctional facilities).^{33,62,67,70,73} Of the 11 studies, 3 found a significant group difference at any time point (n = 878). One found that participants who received prerelease MMT and counseling were less likely to report reincarceration at short-term but not medium-term follow-up, compared with participants who received postrelease MMT referral and counseling, and compared with participants who received counseling only.⁵⁸ Another study found that participants who received case management were less likely to report reincarceration at short-term but not medium-term follow-up, compared with participants who watched an educational video with or without a single counseling session.³³ Among participants in a third study who had been reincarcerated, those who had participated in a therapeutic community reported a longer time period before reincarceration occurred, compared with participants who received outpatient treatment.⁷⁰ One study reported an iatrogenic effect (n = 414), finding that participants who received multiple pre- and postrelease counseling sessions on HIV and reentry were more likely than participants who received a single HIV risk-reduction session to self-report reincarceration at short-term follow-up; this effect disappeared at medium-term follow-up and may be explained by participant tracking strategies at 1 trial site.⁷³

Ten studies measured recidivism by arrest at any follow-up (n = 3477),^{33,55,60,62,67–71} of which 5 reported using a data source other than self-report (e.g., state records).^33,60,70,71 Of the 10 studies, 2 found significantly protective intervention effects at any follow-up (n = 899). One found that the addition of case management after HIV-related jail empowerment groups led to a reduced likelihood of arrest with serious charges at long-term follow-up, compared with participants who did not receive case management.⁶⁸ The other trial evaluated a therapeutic community, and it found that the therapeutic community participants were less likely than outpatient participants to report overall arrest at medium- but not long-term follow-up, and less likely to report arrest for an offense other than parole violation at medium-term follow-up.⁷⁰ One study found a significant iatrogenic effect (n = 378), suggesting that participants who received case management using the Treatment Alternatives to Street Crime model had more arrests according to probation records at medium-term follow-up, compared with participants who received case management that did not use that model.⁶⁰

Seven studies reported any measure of recidivism by self-reported criminal activity at any follow-up (n = 2649).^{33,58,60,70,71} Of these, 3 found a significant difference between groups at any time point (n = 1157). One found that the addition of prerelease MMT to counseling led to significant reductions in frequency of criminal activity at short- and medium-term follow-up⁵⁸; this study also found a benefit of prerelease MMT compared with a postrelease MMT referral at short-term follow-up. A second study found that participants who received 6 months of case management were less likely to report recent criminal activity at medium- but not short-term follow-up, compared with participants who viewed an educational video or who received both the video and a single counseling session.³³ Finally, a third study found that participants who spent 6 months in a therapeutic community before release from incarceration were less likely to engage in criminal activity and drug-related activity at both medium- and long-term follow-up compared with participants in an intensive outpatient program.⁷⁰

Ten studies reported information about intervention acceptability or participant satisfaction.^{42,44,50,51,52,55,58,59,61,62} Four assessed an OST intervention for drug treatment, and all found a low incidence of adverse events,^50,58 high ratings for participant satisfaction with treatment,^44,50 willingness to recommend the treatment to others,⁴⁴ and a high proportion of participants who intended to remain on treatment in the future (which was higher among participants receiving buprenorphine compared with those receiving MMT).⁶² Among the 6 studies of psychosocial interventions that assessed acceptability, acceptability was also high according to satisfaction outcomes,^53,59,61 and general descriptions of participant and staff reception.^42,51,55

Five trials commented on intervention cost.^{42,54,63,72,73} Two trials noted that staff training and time may be comparatively costly for psychosocial interventions delivered in a one-on-one format,^63,72 and 2 trials noted potential cost savings associated with a peer-led intervention for incarcerated men⁵⁴ and a computer-based intervention for a mixed-gender sample of individuals on probation.⁴² A formal cost assessment was available for only 1 study, which found that a multisession intervention with services in both correctional facilities and the community cost approximately $1830 per participant (2009 dollars), whereas a single-session prerelease intervention cost approximately $690 per person.⁷³ The authors concluded that the multisession intervention would be cost-effective if it prevented 1 HIV transmission per 753 participants released from prison.