***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Abstract Objective : To determine the effectiveness of a brief cognitive behavioural intervention in reducing the incidence of sexually transmitted infections among gay men . Design : R and omised controlled trial with 12 months ' follow up . Setting : Sexual health clinic in London . Participants : 343 gay men with an acute sexually transmitted infection or who reported having had unprotected anal intercourse in the past year . Main outcome measures : Number of new sexually transmitted infections diagnosed during follow up and self reported incidence of unprotected anal intercourse . Results : 72 % ( 361/499 ) of men invited to enter the study did so . 90 % ( 308/343 ) of participants returned at least one follow up question naire or re-attended the clinic and requested a check up for sexually transmitted infections during follow up . At baseline , 37 % ( 63/172 ) of the intervention group and 30 % ( 50/166 ) of the control group reported having had unprotected anal intercourse in the past month . At 12 months , the proportions were 27 % ( 31/114 ) and 32 % ( 39/124 ) respectively ( P=0.56 ) . However , 31 % ( 38/123 ) of the intervention group and 21 % ( 35/168 ) of controls had had at least one new infection diagnosed at the clinic ( adjusted odds ratio 1.66 , 95 % confidence interval 1.00 to 2.74 ) . Considering only men who requested a check up for sexually transmitted infections , the proportion diagnosed with a new infection was 58 % ( 53/91 ) for men in the intervention group and 43 % ( 35/81 ) for men in the control group ( adjusted odds ratio 1.84 , 0.99 to 3.40 ) . Using a regional data base that includes information from 23 sexual health clinics in London , we determined that few participants had attended other sexual health clinics . Conclusions : This behavioural intervention was acceptable and feasible to deliver , but it did not reduce the risk of acquiring a new sexually transmitted infection among these gay men at high risk . Even carefully design ed interventions should not be assumed to bring benefit . It is important to evaluate their effects in r and omised trials with objective clinical end points . What is already known on this topic The need for effective HIV prevention strategies based on reducing sexual risk behaviour remains important Few interventions to reduce sexual risk behaviour have been rigorously evaluated using r and omised controlled trials What this study adds This is the first r and omised controlled trial of an intervention addressing sexual behaviour in homosexual men that uses sexually transmitted infections and self reported behaviour as end points The intervention was brief and feasible to use in a busy clinic , but it did not reduce the risk of participants acquiring new infections The potential for behavioural interventions to do more harm than good needs to be taken BACKGROUND Effective interventions are needed to prevent acquisition of HIV infection in men who have sex with men . To date , no behavioural interventions specifically for this risk group have been tested with HIV infection as the primary outcome . METHODS This multisite two-group r and omised controlled phase IIb trial tested the efficacy of a behavioural intervention in preventing HIV infection among 4295 men who have sex with men . The experimental intervention consisted of ten one-on-one counselling sessions followed by maintenance sessions every 3 months . The st and ard condition was twice-yearly Project RESPECT individual counselling . Twice-yearly follow-up visits included testing for HIV antibody and assessment of behavioural outcomes . FINDINGS The rate of acquisition of HIV infection was 18.2 % ( 95 % CI -4.7 to 36.0 ) lower in the intervention group than the st and ard group . Adjustment for baseline covariates attenuated the intervention effect to 15.7 % ( -8.4 to 34.4 ) . The effect was more favourable in the first 12 - 18 months of follow-up . The occurrence of unprotected receptive anal intercourse with HIV-positive and unknown-status partners was 20.5 % ( 10.9 to 29.0 ) lower in the intervention than in the st and ard group . INTERPRETATION The results from the primary analyses allow us to rule out that the experimental intervention is associated with a 35 % lower rate of HIV acquisition than in the st and ard group . The overall estimate of a difference of 18.2 % , more favourable estimates of effect in the first 12 - 18 months , and similar effects on risk behaviours suggest that prevention of HIV infection among men who have sex with men by a behavioural intervention is feasible . Further work should be done to develop more effective interventions At the time of this writing , no r and omized controlled trial ( RCT ) of an intervention to reduce unsafe sex among Latino gay and bisexual men ( LGBM ) had been published . We report the results of an RCT conducted in New York City in which 180 LGBM were assigned either to an intervention developed specifically for this population or to a wait-list control group . The intervention was based on empowerment theory and used factors identified in prior research as determinants of unsafe sex . By eligibility criteria , all men had engaged in unprotected anal intercourse ( UAI )  within two months of the baseline assessment . At first ( two months ) and second ( six months later ) follow-up assessment s , approximately half of the men in the experimental group reported no UAI . Yet , a similar proportion of the control group also reported no UAI . Baseline data indicate that although the men had been the subject of social oppression and sexual prejudice ( homophobia ) , they did not feel disempowered , externally controlled or fatalistic , and they reported self-efficacy and intentionality to enact safer sex . Lessons learned are discussed , as well as notes of caution for future research employing a similar conceptual framework Objectives : To evaluate the effects of an enhanced peer-led intervention on transmission risk behavior and serostatus disclosure of HIV-seropositive gay and bisexual men . Design : A r and omized intervention trial . Methods : HIV-seropositive gay and bisexual men were recruited from New York City and San Francisco and were r and omly assigned to either a st and ard or an enhanced intervention . The st and ard intervention consisted of one session that provided safer sex information . The enhanced intervention consisted of six sessions and included safer sex information , interactive learning activities , and discussion groups that were facilitated by HIV-seropositive peers . Participants completed audio computer-assisted self interview ( A-CASI ) assessment s at baseline and 3 and 6-month follow-ups . Optional testing for sexually transmitted infections was offered at baseline and the 6-month follow-up . Results : A total of 811 participants met the inclusion criteria for outcome analyses . Of these , 85 and 90 % were retained for the 3 and 6-month follow-ups , respectively . Compared with the st and ard intervention , fewer men assigned to the enhanced intervention reported unprotected receptive anal intercourse with a negative or unknown-serostatus partner at 3 months ( 21 versus 26 % , P < 0.05 ) . However , there were no other significant differences in transmission risk or serostatus disclosure at 3 or 6 months . Conclusion : The enhanced intervention was associated with only a limited reduction in transmission risk at 3 months relative to the st and ard intervention . The characteristics of the intervention that may have reduced its efficacy are identified and directions for future research are suggested Behavior change can curtail the spread of acquired immune deficiency syndrome ( AIDS ) . In this study , 104 gay men with a history of frequent AIDS high-risk behavior completed self-report , self-monitoring , and behavioral measures related to AIDS risk . The sample was r and omly divided into experimental and waiting-list control groups . The experimental intervention provided AIDS risk education , cognitive-behavioral self-management training , sexual assertion training , and attention to the development of steady and self-affirming social supports . Experimental group participants greatly reduced their frequency of high-risk sexual practice s and increased behavioral skills for refusing sexual coercions , AIDS risk knowledge , and adoption of " safer sex " practice s. Change was maintained at the 8-month follow-up Objectives The incidence of AIDS is increasing at a higher rate among homosexual Asian and Pacific Isl and ers ( API ) than white homosexual men in the United States . The number of homosexual API men engaging in unsafe sex is increasing at an alarming rate . HIV risk reduction is urgently needed in this population . Subjects and methods We developed and evaluated culturally appropriate brief group counseling with 329 self-identified homosexual API recruited in San Francisco between 1992 and 1994 . Participants were r and omized into a single , 3-h skills training group or a wait-list control group . The intervention consisted of four components : ( 1 ) development of positive self-identity and social support , ( 2 ) safer sex education , ( 3 ) eroticizing safer sex , and ( 4 ) negotiating safer sex . Data were collected at baseline and 3 months after the intervention . Results Significant reductions in number of sexual partners were observed among all treatment subjects , regardless of ethnicity ( P= 0.003 ) . Treatment decreased the number of partners reported at 3-month follow-up by 46 % [ 95 % confidence interval ( CI ) , 28–77 ] . Chinese and Filipino men further benefited from the intervention : treatment subjects from these two ethnic groups reduced unprotected anal intercourse at follow-up by more than half when compared to their counterparts ( odds ratio = 0.41 ; 95 % CI , 0.19–0.89 ; P= 0.024 ) . Conclusions We demonstrated the efficacy of brief group counseling in reducing HIV risk among homosexual API . Cities with significant API population s should adopt culturally tailored skills training as part of HIV prevention strategies for this group of homosexual men This controlled prospect i ve study assessed the effectiveness of a sexual health approach to HIV prevention  for men who have sex with men ( MSM ) . Participants ( N = 422 Midwestern MSM ) were r and omly assigned to the intervention group , who participated in a 2-day comprehensive human sexuality seminar design ed to context ually address long-term risk factors and cofactors , or to the control group , who watched 3 hours of HIV prevention videos .  Risk behavior during the preceding 3 months was measured at baseline , 3-month follow-up , and 12-month follow-up . Any unprotected anal intercourse outside a long-term seroconcordant relationship was the dependent variable . Of the total , 14%-24 % of the participants were considered at risk of acquiring or transmitting HIV . At the 12-month follow-up , the control reported a 29 % decrease in the use of condoms during anal intercourse ; the intervention group reported an 8 % increase ( t = 2.546 ; p = .015 ) . The sexual health seminars appear a promising new intervention at significantly reducing unprotected anal intercourse between men HIV prevention , by intervening within social networks , is potentially important but highly understudied . Approaches that systematic ally identify , train , and enlist known social influence leaders to advise members of their own networks in risk reduction constitute ways to reach hidden population segments , persons who are distrustful of authorities but trust their peers , and those who can not be reached through traditional professionally delivered counseling . This article illustrates and provides evaluation data on a program that recruited 14 intact social networks of young men who have sex with men ( YMSM ) in St. Petersburg , Russia , and Sofia , Bulgaria . Sociometric measures were used to identify the social leader of each network , and baseline  risk assessment measures were administered to all members of each social network . The sociometrically determined leaders then attended a six-session group program that provided training and guidance in how to carry out theory-based and tailored HIV prevention conversations with members of their own social networks . Four months after leaders completed the program , all network members were readministered risk assessment measures . Pre- to postintervention data revealed that the program produced : ( 1 ) increases in the level and comfort with which network members talked about AIDS prevention topics in their daily conversations ; ( 2 ) increased network-level AIDS risk reduction knowledge and improved risk reduction norm perceptions , attitudes , behavioral intentions , and self-efficacy ; and ( 3 ) increased condom use levels among network members . Although not a controlled , r and omized trial , these program evaluation findings strongly support the feasibility of social network-level HIV prevention approaches CONTEXT High-risk sexual behavior is increasingly prevalent among men who have sex with men ( MSM ) and among men with a history of repeat testing for HIV . OBJECTIVES The study assessed whether one counseling intervention session focusing on self-justifications ( thoughts , attitudes , or beliefs that allow the participant to engage in high-risk sexual behaviors ) at most recent unprotected anal intercourse ( UAI ) is effective in reducing future high-risk behaviors among HIV-negative men . DESIGN , SETTING , AND PARTICIPANTS A r and omized , controlled , counseling intervention trial was conducted at an anonymous testing site in San Francisco , California , between May 1997 and January 2000 . Participants were 248 MSM with a history of at least one previous negative HIV test result and self-reported UAI ( receptive or insertive ) in the previous 12 months with partners of unknown or discordant HIV status . Two intervention groups received st and ard HIV test counseling plus a cognitive-behavioral intervention , and two control groups received only st and ard HIV test counseling . Follow-up evaluation was at 6 and 12 months . MAIN OUTCOME MEASURE Number of episodes of UAI with non primary partners ( of unknown or discordant HIV status ) in the 90 days preceding the interview was measured via self-report during face-to-face interview . RESULTS A novel counseling intervention focusing on self-justifications significantly 
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The Task Force concluded that the findings are applicable to MSM aged 20 years or older , across a range of setting s and population s , assuming that interventions are appropriately adapted to the needs and characteristics of the MSM population of interest .
Based on findings from economic evaluation studies , the Task Force also concluded that group- and community-level HIV behavioral interventions for adult MSM are not only cost effective but also result in actual cost savings .