Conhecimento de HIV/Aids entre homens que fazem sexo com homens: teoria de resposta ao item

OBJECTIVE To 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. METHODS Multicenter, 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. RESULTS Overall, 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. CONCLUSIONS Item 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.OBJETIVO Avaliar o nível de conhecimento de HIV/Aids entre homens que fazem sexo com homens no Brasil, utilizando o modelo de traço latente da Teoria de Resposta ao Item. MÉTODOS Estudo multicêntrico, transversal, que ocorreu entre 2008 e 2009 em 10 cidades brasileiras. Foram recrutados 3.746 homens que fazem sexo com homens pela técnica amostral Respondent Driven Sampling. O conhecimento em HIV/Aids foi apurado a partir de dez afirmativas da entrevista realizada face a face e os escores foram obtidos utilizando o modelo logístico de dois parâmetros (discriminação e dificuldade) da Teoria de Resposta ao Item. O funcionamento diferencial dos itens foi verificado, analisando as curvas características dos itens pela idade e escolaridade. RESULTADOS Os escores de conhecimento estimados pela Teoria de Resposta ao Item não ultrapassaram o valor 6,0 (escala de 0-10), com média e mediana de 5,0 (DP = 0,9) e 5,3, respectivamente, e com 40,7% da amostra com níveis de conhecimento abaixo da média. Algumas crenças ainda existem nessa população sobre a transmissão do vírus por picadas de insetos, pelo uso de banheiros públicos e pelo compartilhamento de utensílios durante as refeições. Com relação aos parâmetros dificuldade e discriminação, oito itens ficaram abaixo da média da escala de conhecimento e considerados muito fáceis, e quatro itens apresentaram parâmetros de discriminação muito baixos (< 0,34). A ausência de itens difíceis contribuiu para a imprecisão da medida do conhecimento entre aqueles com nível médio e superior. CONCLUSÕES A análise da Teoria de Resposta ao Item, centrada nas propriedades individuais de cada item, permite a obtenção de medidas que não variam ou dependem do questionário utilizado, o que proporciona uma melhor apuração e precisão dos escores de conhecimento. Escalas válidas e confiáveis são fundamentais para monitorar o conhecimento em HIV/Aids nessa população ao longo do tempo e em diferentes regiões geográficas, vantagem que esse modelo psicométrico traz

Mortalidade infantil e condições sociodemográficas no Ceará, em 1991 e 2000

OBJECTIVE: To assess ecological models to describe infant mortality rate in Ceara (Northeastern Brazil) in two different periods of time. METHODS: This was a cross-sectional ecologic study of two years, 1991 and 2000, using non-matching information per municipalities. Estimates on the infant mortality rate of the Instituto de Pesquisas Econômicas Aplicadas (Institute of Applied Economic Research) have been used. For the remaining indicators different sources of the System of Health Information were used. The main risk factors were assessed using multiple linear regression. RESULTS: In 1991, the variables that predicted infant mortality rate (R2=0.3575) were: small houses (beta=0.0043; rho=0.010), proportion of inhabitants with tap water in the household (beta=-0.0029; rho=0.024), urbanization rate (beta=0.0032; rho=0.004), fecundity rate (beta=0.0351; rho=0.024), the proportion of children working at 10-14 years (beta=0.0049; rho=0.017), proportion of families with income < &frac12; minimum wage (beta=0.0056; rho=0.000), that can read and write (beta=-0.0062; rho=0.031). In the year 2000, the following possible determinants were identified (R2=0.3236): the proportion of childrenOBJETIVO: Analisar os modelos explicativos ecológicos para a taxa de mortalidade infantil no Ceará, em dois períodos distintos. MÉTODOS: Estudo ecológico transversal de dois anos censitários, 1991 e 2000, a partir de informações desagregadas por municípios do Ceará. Foram utilizadas as estimativas da taxa de mortalidade infantil do Instituto de Pesquisas Econômicas Aplicadas. Para os demais indicadores foram utilizadas diferentes fontes do Sistema de Informação de Saúde. Os principais fatores de risco foram encontrados empregando-se regressão linear múltipla. RESULTADOS: Para 1991, as variáveis preditoras da mortalidade infantil (R2=0,3575) nos municípios foram: proporção de residências pequenas (beta=0,0043; ro=0,010), de pessoas que vivem em domicílios com água encanada (beta=-0,0029; ro=0,024), de crianças de dez a 14 anos que trabalham (beta=0,0049; ro=0,017), de alfabetizados (beta=-0,0062; ro=0,031), taxa de urbanização (beta=0,0032; ro=0,004), taxa de fecundidade total (beta=0,0351; ro=0,024), chefes de família com renda mensal menor que meio salário mínimo (beta=0,0056; ro=0,000). Em 2000, os possíveis determinantes (R2=0,3236) foram: proporção de crianças menores de dois anos desnutridas (beta=0,0064; ro=0,024), de imóveis com esgotamento sanitário adequado (beta=-0,0024; ro=0,010), de despesa com recursos humanos da saúde em relação à despesa total em saúde (beta=-0,0024; ro=0,027), de valor da produção vegetal em relação ao total do estado (beta=-0,1090; ro=0,001), de mulheres alfabetizadas (beta=-0,0068; ro=0,044), intensidade da pobreza (beta=0,0065; ro=0,002) e índice de envelhecimento (beta=-0,0100; ro=0,006). CONCLUSÕES: Embora as variáveis não tenham sido exatamente as mesmas para os anos, percebeu-se tendência de mudança dos determinantes da mortalidade infantil, excetuando-se os indicadores de educação, renda e saneamento. A queda generalizada da fecundidade resultou na perda de seu poder descriminante, sendo substituída pelo índice de envelhecimento. Outra tendência observada foi a substituição de variáveis demográficas por indicadores de assistência à saúde

Viral hepatitis in female sex workers using the Respondent-Driven Sampling

OBJECTIVE To estimate the prevalence of hepatitis B virus and C virus infections and their genotypes and analyze the risk factors for the markers of exposure to hepatitis B virus in female sex workers in a region of intense sex trade. METHODS This is a cross-sectional study performed with four hundred and two female sex workers in Goiânia, Brazil. Data have been collected using the Respondent-Driven Sampling. The women have been interviewed and tested for markers of hepatitis B and C viruses. Positive samples have been genotyped. The data have been analyzed using the Respondent-Driven Sampling Analysis Tool, version 5.3, and Stata 11.0. RESULTS The adjusted prevalence for hepatitis B virus and C virus were 17.1% (95%CI 11.6–23.4) and 0.7% (95%CI 0.1–1.5), respectively. Only 28% (95%CI 21.1–36.4) of the participants had serological evidence of vaccination against hepatitis B virus. Being older (>; 40 years), being single, having a history of blood transfusion and use of cocaine, and ignoring the symptoms of sexually transmitted infections were associated with positivity for hepatitis B virus (p < 0.05). We have detected the subgenotype A1 of hepatitis B virus (n = 3) and the subtypes of hepatitis C virus 1a (n = 3) and 1b (n = 1). CONCLUSIONS We can observe a low prevalence of infection of hepatitis B and C viruses in the studied population. However, the findings of the analysis of the risk factors show the need for more investment in prevention programs for sexual and drug-related behavior, as well as more efforts to vaccinate this population against hepatitis B. The genotypes of the hepatitis B virus and C virus identified are consistent with those circulating in Brazil

Risk behavior score: a practical approach for assessing risk among men who have sex with men in Brazil

HIV/AIDS epidemic is not well controlled, and multiple sexual behavior factors help explain high rates of HIV infection among men who have sex with men (MSM). This article proposes to exam the use of a potential risk behavior score for HIV infection, based on the type and number of sexual partners, and condom use, and their associated factors in a sample of MSM in Brazil. A cross sectional RDS (Respondent Driven Sampling) study was performed among 3738 MSM aged 18+ years old from ten Brazilian cities. The risk behavior score was composed by the number of male partners and anal condom use in the last year with steady, casual, and commercial partners. Most participants were 25+ years old (58.1%), non-white (83.1%), and single (84.9%). Final weighted ordinal logistic model showed that age ≤ 25 years old (p = 0.037), homosexual or bisexual identity (p < 0.001), sexual initiation before 15-year-old (p < 0.001), having sex with men only in the last 12 months (p < 0.001), frequent alcohol and illicit drug use (p < 0.001), and use of local sites to meet sexual partners in the last month were independently associated with higher scores of risky behavior. Specific strategies should be developed aimed at the MSM population. Additionally, pre-exposed prophylaxis (Prep) should be considered for those at higher score as a strategy for reducing risk for HIV infection in this population. Keywords: Homosexuals, High-risk sex, Unsafe sex, HIV, AID

Fatores associados ao baixo conhecimento sobre HIV/AIDS entre homens que fazem sexo com homens no Brasil

Este estudo transversal analisou os fatores de vulnerabilidade social, individual e programática associados ao baixo conhecimento em HIV/AIDS entre homens que fazem sexo com homens (HSH). A técnica amostral Respondent Driven Sampling (RDS) foi utilizada em dez cidades brasileiras. Os escores de conhecimento em HIV/AIDS foram estimados pela Teoria de Resposta ao Item e categorizados em três níveis: alto, médio e baixo conhecimento. O modelo de regressão logística ordinal foi utilizado para a análise. Dentre os 3.746 HSH, encontrou-se 36,6%, 37,4% e 26% com alto, médio e baixo conhecimento, respectivamente. No modelo final, apresentaram associação com o baixo conhecimento: escolaridade ≤ 8 anos, cor da pele não branca, critério de classe econômica C e D-E, idade < 25 anos, ter somente um parceiro sexual e nunca ter feito o teste anti-HIV. É fundamental melhorar o nível de conhecimento sobre HIV/AIDS entre os jovens HSH, com condições socioeconômicas desfavoráveis. Intervenções focadas nos fatores de vulnerabilidade programática podem contribuir para a redução dos fatores individual e social

HIV/AIDS knowledge among men who have sex with men: applying the item response theory

OBJECTIVE To 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. METHODS Multicenter, 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. RESULTS Overall, 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. CONCLUSIONS Item 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