Ninety-three publications reporting data from 74 RCTs that evaluated 75 STI prevention interventions (numbers of participants not reported) were included in the review. The authors reported that study quality was high overall. Follow-up rates ranged from 30% to 100%.
Behavioural interventions: Seventeen (reported as 18 in a table) out of 27 interventions found positive effects on STI risk. One intervention showed negative effects and nine showed no effect. Positive effects ranged from 9% to 83%. Subgroup analyses included individual versus group therapy, skills building interventions versus interventions without skills building and risk reduction counseling control groups versus general health promotion control groups. Where reported, adherence rates ranged from 47% to 100%.
Physical barrier methods: Four studies found no effects on STI risk when compared with standard male condoms with or without risk reduction information and education. Where reported, adherence rates ranged from 7% to 97%.
Vaginal microbicides: Three out of 12 studies found a positive effect on STI risk. Two studies found an adverse effect and seven studies found no effect. Where reported, adherence rates ranged from 47% to 90%.
Male circumcision: Three out of four studies found a positive effect on STI risk and one study found no effect.
Partner services: Four out of seven studies found a positive effect on STI risk and three studies found no effect. Where reported, adherence ranged from 25% to 88%.
Treatment: Seven of eight studies found a positive effect on STI risk and one study found no effect. Positive effects ranged from 30% to 60% reduction in risk. Where reported, adherence ranged from 70% to 100%.
Vaccines and passive immunization: Ten out of 12 studies found a positive effect on STI risk and two studies found no effect. Where reported, adherence ranged from 76% to 100%.
Multicomponent interventions: One study found an adverse effect on STI risk as a result of a multicomponent intervention. Adherence rates were not reported.
Where possible, the authors reported outcomes for different STI infections.