Abstract: | OBJECTIVETo evaluate the level of HIV/AIDS knowledge among men who have sex with men
in Brazil using the latent trait model estimated by Item Response
Theory.METHODSMulticenter, cross-sectional study, carried out in ten Brazilian cities
between 2008 and 2009. Adult men who have sex with men were recruited (n =
3,746) through Respondent Driven Sampling. HIV/AIDS knowledge was
ascertained through ten statements by face-to-face interview and latent
scores were obtained through two-parameter logistic modeling (difficulty and
discrimination) using Item Response Theory. Differential item functioning
was used to examine each item characteristic curve by age and schooling.RESULTSOverall, the HIV/AIDS knowledge scores using Item Response Theory did not
exceed 6.0 (scale 0-10), with mean and median values of 5.0 (SD = 0.9) and
5.3, respectively, with 40.7% of the sample with knowledge levels below the
average. Some beliefs still exist in this population regarding the
transmission of the virus by insect bites, by using public restrooms, and by
sharing utensils during meals. With regard to the difficulty and
discrimination parameters, eight items were located below the mean of the
scale and were considered very easy, and four items presented very low
discrimination parameter (< 0.34). The absence of difficult items
contributed to the inaccuracy of the measurement of knowledge among those
with median level and above.CONCLUSIONSItem Response Theory analysis, which focuses on the individual properties of
each item, allows measures to be obtained that do not vary or depend on the
questionnaire, which provides better ascertainment and accuracy of knowledge
scores. Valid and reliable scales are essential for monitoring HIV/AIDS
knowledge among the men who have sex with men population over time and in
different geographic regions, and this psychometric model brings this
advantage. |