Purcell 2007.

Methods	Randomized controlled trial
Participants	The study location was community venues in Baltimore, Miami, New York, and San Francisco, USA 486 participants were randomized to the intervention group and 480 participants were randomized to the control group The inclusion criteria were confirmed HIV‐positive patients over 18 years old, who used injected drugs in the past year, had at least 1 opposite‐sex sexual partner in the past 3 months, who agreed to a blood draw, had not been enrolled in the cross‐site pilot study or an intervention study conducted by a principal investigator, lived within the study area and were willing to provide contact information, were English speaking, and were available for the first intervention session
Interventions	Intervention: PEER MENTORING INTERVENTION The peer mentoring intervention sessions were delivered twice a week for 5 weeks and included 7 group sessions, 2 individual sessions, and 1 ''peer volunteer activity'' (PVA), during which participants went to a local service organization for 2 to 4 hours to observe, participate, and practice peer mentoring skills. The first session focused on setting group rules and the power of peer mentoring, 2 group sessions and 1 individual session focused on utilization of HIV primary care and adherence, and 3 group sessions and 1 individual session focused on sex and drug risk behaviors. Risk messages were communicated using posters and handouts with risk hierarchies that helped to form individualized risk plans discussed during the individual session focusing on sex and injection behaviors. The final group session focused on review and reinforcement of motivation and skills for behavior change and ended with a graduation ceremony. For both treatment groups, a resource table that provided information about local services available for medical care, support groups, drug treatment, and prevention resources such as pamphlets and male and female condoms was available during and after every session Control: VIDEO DISCUSSION INTERVENTION Control participants had similar access to general information resources and risk reduction information and resources as intervention participants, and received equal attention during the study regarding groups sessions, but not the 2 individual sessions as did the intervention participants. Participants in the control group took part in 8 group sessions over 5 weeks. For all but session 1, the control sessions were led by the same 2 facilitators who led the intervention sessions. Participants in the control group watched documentary or self help videos focused on issues relevant to HIV‐positive intravenous drug users, followed by facilitated discussion. Topics directly related to the intervention outcomes were avoided or minimized. Community resources and risk reduction information and tools were available at every control session
Outcomes	The adherence measure was participant self report, measured at baseline, 3, 6, and 12 months. Good adherence was defined as having taken 90% of antiretroviral medications in the prior 7 days The patient outcomes were sexual behavior, injection behavior, and utilization of HIV care (2 times or more in the past 6 months) assessed at baseline, 3 months (not care utilization), 6 months, and 12 months by means of audio computer‐assisted self interviewing (A‐CASI)
Notes	―
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer randomization was used. "One staff member at each site who was not an intervention facilitator used a computer program to assign participants to 1 of the 2 intervention conditions." (pg s36)
Allocation concealment (selection bias)	Unclear risk	No information was provided about how allocation was handled
Selective reporting (reporting bias)	Unclear risk	MEMS results are not reported, only self reported adherence, but since all results are negative it is assumed that it is unlikely MEMS was positive and thus low risk of bias
Other bias	Low risk	The study seems to be free of other types of bias
Blinding of outcome assessment (detection bias) Adherence measure	Low risk	(PRIMARY) SELF REPORT ‐ QUESTIONNAIRE ‐ No mentioning of (not) blinding data collection personnel to the group allocation. But A‐CASI is used to administer the interviews ‐ objective measure
Blinding of outcome assessment (detection bias) Patient outcome	Low risk	(PRIMARY) SEXUAL BEHAVIOR ‐ A‐CASI used to administer the interviews. This is an objective measure of outcome
Blinding of participants (performance bias) Adherence measure	High risk	(PRIMARY) SELF REPORT ‐ QUESTIONNAIRE ‐ Patients likely not blind due to the nature of the intervention
Blinding of participants (performance bias) Patient outcome	High risk	(PRIMARY) SEXUAL BEHAVIOR ‐ Patients likely not blind due to the nature of the intervention
Blinding of personnel (performance bias) Adherence measure	Low risk	(PRIMARY) SELF REPORT ‐ QUESTIONNAIRE ‐ No mentioning of blinding of key personnel noted. However, A‐CASI is used to administer the interviews ‐ objective measure
Blinding of personnel (performance bias) Patient outcome	Low risk	(PRIMARY) SEXUAL BEHAVIOR ‐ A‐CASI used to administer the interviews. This is an objective measure of outcome
Incomplete outcome data (attrition bias) Adherence measure	Unclear risk	(PRIMARY) SELF REPORT ‐ QUESTIONNAIRE ‐ Attrition for measuring adherence was higher in the intervention group. Although the authors state that they repeated the models with imputation of missing data, which showed no differences, no details are provided
Incomplete outcome data (attrition bias) Patient outcome	Low risk	(PRIMARY) SEXUAL BEHAVIOR ‐ Missing data are balanced between groups, but on the border of significant (20%). However, percentage of missing data is somewhat lower at the other visits