Jemmott 2005.

Methods	DESIGN: Single centre RCT. LENGTH OF FOLLOW‐UP: 3, 6 and 12 months after intervention. DATA ANALYSIS: Analysis appears to be based on the numbers completing follow up. Sample sizes not reported for outcome point estimates. ATTRITION RATE: Completed 3 months: Group 1=208/219, 95% ); Group 2=210/228 (92%); Group 3=225/235 (96%) Completed 6 months: Group 1=206/219 (94%); Group 2=206/228 (90%); Group 3=221/235 (94%) Completed 12 months: Group 1=199/219 (91%); Group 2=196/228 (86%); Group 3=209/235 (89%) Reported that there were no significant differences between the groups in the numbers who attended at least one, two or all three follow up assessments. Overall, 87.8% and 82.3% returned, respectively, for 6 and 12 month STI examinations; reported that the return rates did not differ significantly between the groups. UNIT OF DATA ANALYSIS: Individuals (as randomised). SAMPLE SIZE CALCULATION: With α=0.05, 2‐tailed, a total sample size of 506 participants completing the trial was projected to provide a power of 80% to detect a 0.25 SD difference in self‐reported frequency of unprotected sex between each of Groups 1 and 2 and Group 3. EQUIVALENT STUDY GROUPS AT BASELINE: The groups appear balanced and analyses found no statistically significant group differences, for age, proportion African‐American, proportion with children, proportion living with mother, knowledge of STIs and condom use, beliefs or sexual behaviour variables. PROCESS EVALUATION: Participants reported their satisfaction with the intervention and its learning value (data not extracted).
Participants	NUMBER RANDOMISED: 682 AGE, mean (SE) years: Group 1=15.53 (0.10); Group 2=15.49 (0.10); Group 3=15.52 (0.10); overall range 12 to 19. SOCIO‐ECONOMIC STATUS: Not reported other than setting was a low income inner city location. ETHINCITY/RACE: Overall 68% African‐American; 32% Latino (of whom 92.7% were Puerto Rican). Proportion African‐American: Group 1=68.1%; Group 2=68.0%; Group 3=67.6%. LOCATION: USA, Pennsylvania; inner city area of Philadelphia PREVIOUS STI: Tested positive for chlamydia, gonorrhoea or trichomoniasis at baseline: Group 1=22.8%; Group 2=26.0%; Group 3=16.9%. SEXUAL RISK BEHAVIOUR: Participants were all sexually experienced but not pregnant. % sexually active in past 3 months: Group 1=85.6; Group 2=85.8; Group 3=89.8. Mean (SE) number of days unprotected sex in past 3 months: Group 1=2.52 (0.50); Group 2=3.22 (0.45); Group 3=3.02 (0.50). Mean (SE) number of sex partners in past 3 months: Group 1=1.04 (0.05); Group 2=1.14 (0.05); Group 3=1.11 (0.04). % with multiple partners in past 3 months: Group 1=12.3; Group 2=18.9; Group 3=16.4. OTHER: Participants had volunteered for the Women's Health Project and were patients at the adolescent medicine clinic where the interventions took place.
Interventions	GROUP 1: Skills‐based HIV/STI risk reduction intervention (n = 235) YEAR STARTED: Not reported. PROVIDERS: 14 African‐American women of mean age 38.2 years and with at least a degree qualification and experience working with inner‐city adolescents (not reported how the 14 were distributed across the intervention groups). SETTING: Inner city hospital‐based adolescent medicine clinic that provided confidential and free family planning services for low income youth. TYPE: Single session with groups of 2 to 10 (mean 5.3) participants involving videotapes, games and experiential exercises providing information/education about HIV/STI risks & transmission, risk reduction responsibilities & condom use. Also provided practical skills development for condom use (with an anatomical model) and condom negotiation (based on role playing). DURATION: 250 minutes; single session. THEORETICAL BASIS: Based on Cognitive Behavioural Theory (references provided) and formative elicitation research. STIs COVERED: HIV and STIs in general. GROUP 2: Information‐based HIV/STI risk reduction intervention (n = 228) TYPE: As Group 1 in structure, information content and timing, but omitted practical skills development (condom practice and condom negotiation role play) components. All other details as Group 1. GROUP 3: Health promotion control intervention (n = 219) TYPE: Participants received a health promotion control intervention designed to be as valuable and enjoyable as the Group 1 and Group 2 interventions. It covered information/education, beliefs and practical skills development in relation to reducing the risks of cardiovascular disease, cancer and stroke. The focus was on food selection and preparation, physical activity, breast self examination, smoking and alcohol use. There was no HIV/STI content. STIs covered: None. All other details as Group 1.
Outcomes	PRIMARY: Self‐reported number of days of unprotected sexual intercourse in the previous 3 months. SECONDARY: Number of days of sexual intercourse whilst intoxicated (drugs and alcohol) in the previous 3 months; Number of days of unprotected sex whilst intoxicated (drugs and alcohol) in the previous 3 months; Number of sexual partners in the previous 3 months; Incidence of biologically confirmed chlamydia, gonorrhoea and/or trichomoniasis in the previous 3 months; Intentions to use condoms; Knowledge about STIs and condom use; Beliefs about using condoms.
Notes	COST DATA: Reported that participants were reimbursed up to $120 for participation ($40 for completing pre‐ and post‐intervention questionnaires; $25, $25 and $30 for attending 3, 6 and 12 months follow up respectively).
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Low risk	Stated that participants were stratified by age and randomly allocated to the intervention groups based on computer‐generated random number sequences (no other details provided).
Allocation concealment?	Unclear risk	No information provided.
Blinding? All outcomes	Low risk	Stated that proctors blind to the participants' intervention assignment collected questionnaire data and that STI screening was done by clinicians blind to participants' intervention assignment. However, it is unclear whether the proctors were involved in outcome assessment or just data collection.
Incomplete outcome data addressed? All outcomes	Unclear risk	Analysis appears to be based only on those who completed follow up, but sample sizes were not reported for outcomes. Stated that there were no significant differences between groups in the numbers who attended follow up assessments or who returned for STI examinations. However, statistically significant differences were observed between completers and drop outs for: frequency of sex while intoxicated, frequency of unprotected sex while intoxicated, proportion not living with mother (all were higher among drop outs); and ethnicity (Latinos were more likely to drop out than African‐Americans).
Free of selective reporting?	Low risk	Data for all the outcomes reported in the methods section were provided in the results section.
Free of other bias?	Unclear risk	Unclear