Sampling design and recruitment

Written by Suzi on . Posted in russianbrides

Sampling design and recruitment

Each round associated with IBBSS utilized respondent driven sampling provided towards the concealed nature of MSM and therefore enables contrast between and across rounds. Respondent driven sampling (RDS) happens to be described in more detail in past studies 22, 23. Fleetingly, RDS is really a modified chain referral sampling that is non-random of recruitment that adjusts for the non-randomness employing a mathematical model that loads each sample recruited 23. Inclusion criteria had been male aged 16 years and above with a brief history of oral and/or anal contact that is sexual another guy within the a few months before the study. Known MSM, designated as “seeds” began the chain associated with the recommendation community and make use of vouchers to recruit their peers in to the research. Ten seeds had been chosen for every circular and seeds had been diversified by age, academic status and status that is socioeconomic. To prevent an over-representation of MSM with comparable attributes, vouchers restricted to three per recruit was utilized 23, 24. In addition, to prevent perform enrollment, only 1 screener had been utilized, just one individual had been authorized to reimburse MSM that has effectively recruited their peers and just one location ended up being utilized. Each voucher had been redeemable and yielded N500 approx. $3 USD being a motivation for participating, with one more N500 provided to a recruit for every effective participant that is additional. Total payment ended up being restricted to a maximum settlement of n2000 approximately $12 USD. Test size for the 2007 IBBSS had been predicted centered on an assumed HIV prevalence of 15%, a design aftereffect of 2.0 and amount of accuracy of 0.05. For the 2010 and 2014 IBBSS, test size had been projected to identify a 10% differ from the round that is subsequent.

Data collection

Structured close-ended interviewer administered questionnaires elicited information on socio-demographic traits, form of intercourse lovers and sexual danger habits. Interviews had been carried out in MSM organizations that are friendly in all the study states. Transactional sex ended up being examined both with female and male lovers. Variety of rectal intercourse practiced had been classified as “insertive penile intercourse” or “receptive penile intercourse” in past times a few months. HIV danger perception had been examined by asking MSM “do you are feeling you may be susceptible to disease with HIV? ” with reaction choices being “yes or no”. Consistent condom use with intimate lovers during transactional and sex that is non-transactional evaluated by asking the concerns “how often did you or your male partner make use of condom each time you had intercourse within the last few 6 months? ” while condom usage at final intercourse had been examined because of the concern “the last time you’d anal intercourse did you or your partner make use of a condom? ”. Transactional sex had been examined by asking “have you received cash or present in return for intercourse within the last six months? ” Written consent had been acquired from all individuals both for behavioural and biological the different parts of the study.

Laboratory testing

Detection of HIV during most of the studies ended up being regularly carried out by fast test utilizing blood that is whole obtained from a finger prick. In line with the nationwide HIV assessment guideline, a synchronous algorithm of Determine (Alere health, United States Of America) and Unigold (Trinity Biotech, Plc, Bray, Ireland) had been utilized to determine HIV sero-positivity while status of discordant tests had been verified by using Stat Pak (Chembio Diagnostic techniques, ny, United States Of America).

Data administration and analysis

Data from each research state had been entered centrally making use of CS professional variation 3.2 and 25% of questionnaires underwent double-data entry to make sure information quality. Behavioural and biological data had been linked by research identification that is unique for every participant. Information from each round had been merged and analyzed utilizing STATA 14.0 (STATA Corporation). Descriptive statistics of demographic, behavioural, and variables that are biological carried out. The Cochran-Armitage Chi Square trend test had been utilized to compare differences when considering categorical factors across various rounds of IBBSS, even though the Kruskal-Wallis test had been utilized to compare variations in constant factors across various rounds of IBBSS. To determine associations between HIV and predictor factors (Tables), bivariate regression that is logistic had been carried out with p value ?0•2 designated as the cutoff for addition in multivariate logistic regression models. Variables were retained when they attained a p value ?0•05 within the multivariate analysis. The predictor factors had been considering information from literary works that revealed a link involving the factors and HIV.


Table 1 highlights the sociodemographic data of MSM throughout the three rounds associated with the IBBSS. A complete of 897, 1545 and 3611 MSM had been surveyed in 2007, 2010 and 2014 correspondingly. Lots of the participants had been aged 20–24 years in 2007 (61%) and 2014 (46%), whilst in 2010, almost half (47%) associated with respondents had been 25 years or older. Over 85% associated with respondents had never ever hitched in each round associated with study. Almost all the participants had finished at the least level that is secondary, and this ended up being greatest among participants in 2007 with 63per cent followed closely by participants in 2014 (55%).

Intimate danger Behaviours

The median quantity of insertive anal lovers ended up being constant between 2007 and 2010 with about 50% of this participants reporting insertive anal sex (IAS) with at the least two lovers interquartile range (IQR 1–4) within the last a few months. For receptive anal sex (RAS), a median of two partners that are sexual reported in 2007 whilst it ended up being one partner both in 2010 and 2014. Overall, about a third had engaged in transactional intercourse in 2007 (95% self- self- confidence interval (CI): 30–36%) and 2014 (32–35%), although it had been about two-fifths this year (36–41%). Consistent condom use, whenever intercourse ended up being sold increased steadily from 35% (27–44%) to 79% (74–83%) between 2007 and 2014. Likewise, constant condom used in days gone by six months ahead of the study during compensated intimate encounters increased from 35% (30–41%) in 2007 to 61per cent (58–64%) in 2014. For non-commercial lovers, constant condom usage increased from 32per cent (29–36%) in 2007 to 51percent (49–53%) in 2014. For self-reported experiences of sexually transmitted illness (STI), there was clearly a rise from 7% (5–9%) in 2007 to 15per cent (13–17%) this year and 19per cent (17–20%) in 2014.