**3.1.1 Study population**

According to data and the results of some seroprevalence studies, levels of HIV prevalence are between 10 and 20% among MSM. As mentioned in section 2, this specific

The SIALON Project: Report on HIV Prevalence

variables, as well as to access and barriers to VCT.

(condom use) and 23 (HIV prevalence) were included.

starting in November 2008 and ending in October 2009.

**3.2 Data collection and analysis** 

**3.2.1 Questionnaire** 

ECDC indicators.

**3.2.2 Enrolment** 

specific piloting was conducted.

**3.2.3 Statistical analysis** 

and Risk Behaviour Among MSM in Six European Cities 211

The SIALON questionnaire was specifically designed according to the international literature and according both to the study design and the data collection procedures. The self-administered pen-and-paper questionnaire was developed to obtain information on a range of different aspects and taking into account both UNGASS and ECDC indicators. The first part refers to background data. The second part lists items on sexual practices, riskreducing strategies, condom use, STI history and self-reported/perceived serostatus.

Moreover, questions regarding number of both steady and casual partners were foreseen, as well as frequency and type of sexual practices in both cases. In construing the different questions, specific attention was paid to the social/cultural/environmental and contextual

From a structural point of view, the questionnaire contained items referring to different time-spans: last 12 months, last 6 months, and last time (last sexual intercourse). This structure allowed to include all items needed for the construction of the UNGASS and

In terms of the UNGASS and ECDC indicators themselves, according to the WHO-UNAIDS documents, questions referring to UNGASS 8 (testing), 9 (prevention campaigns), 19

Finally, specific attention was paid to the time span required to fulfill the questionnaire: a maximum of 20 minutes was required for completing the questionnaire. For this purpose,

With regard to the enrolment of subjects, a specific easy-to-use and practical manual was provided to all data collectors, in order to standardise all procedures and to guarantee the safety and reliability of data collected. Following the data collection calendar created through the TLS method, trained field workers from gay associations attended the different gay venues in specific time-location units. The self-administered pen-and-paper questionnaires were distributed, as well as the Oracol devices for oral fluid collection (Malvern Medical Developments, Worcester, UK). Both self-completed questionnaires (behavioural data) and oral fluid samples (biological data) were collected for each subject. A unique barcode for each subject was used to link behavioural and biological information.

Finally, regarding the enrolment period, this varied between the different participating cities, according to the different situations and calendars (from 2 months to 9 months),

Mean, median, standard deviation, quartiles and inter-quartiles were calculated and proportions with 95% confidence intervals (CI) were adopted for all variables and indicators. With regard to the UNGASS indicators calculation, specific reference to the UNGASS-WHO

publications was made. Finally, STATA 11 survey commands suite was used.

sub-population continues to be at high risk of HIV infection, especially in Europe, and according to the available data a hidden HIV epidemic seems currently underway (ECDC, 2010; Likatavi ius et al., 2008). Because of a high level of risk sexual practices, MSM become a key population for HIV surveillance. In addition, especially because of stigma, a low level of VCT is reported, particularly among hard-to-reach MSM who do not attend health services regularly. Moreover, since the introduction of HAART, AIDS has become less indicative of the underlying trends in HIV infection, for this population in particular. For these reasons, field research and surveillance activities targeting this specific population seem to be essential in monitoring the HIV epidemic and in developing preventive action in Europe.
