Reliability of a questionnaire on substance use among adolescent students, Brazil

• Autor(a) principal: Machado Neto,Adelmo de Souza
• Data de Publicação: 2010
• Outros Autores: Andrade,Tarcisio Matos, Fernandes,Gilênio Borges, Zacharias,Helder Paulo, Carvalho,Fernando Martins, Machado,Ana Paula Souza, Dias,Ana Carmen Costa, Garcia,Ana Carolina Rocha, Santana,Lauro Reis, Rolin,Carlos Eduardo, Sampaio,Cyntia, Ghiraldi,Gisele, Bastos,Francisco Inácio
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Revista de Saúde Pública
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0034-89102010000500008
• topic: Questionnaires; Adolescent; Adolescent Behavior; Illicit drugs; Reproducibility of Results

OBJECTIVE: To analyze reliability of a self-applied questionnaire on substance use and misuse among adolescent students. METHODS: Two cross-sectional studies were carried out for the instrument test-retest. The sample comprised male and female students aged 1119 years from public and private schools (elementary, middle, and high school students) in the city of Salvador, Northeastern Brazil, in 2006. A total of 591 questionnaires were applied in the test and 467 in the retest. Descriptive statistics, the Kappa index, Cronbach's alpha and intraclass correlation were estimated. RESULTS: The prevalence of substance use/misuse was similar in both test and retest. Sociodemographic variables showed a "moderate" to "almost perfect" agreement for the Kappa index, and a "satisfactory" (>0.75) consistency for Cronbach's alpha and intraclass correlation. The age which psychoactive substances (tobacco, alcohol, and cannabis) were first used and chronological age were similar in both studies. Test-retest reliability was found to be a good indicator of students' age of initiation and their patterns of substance use. CONCLUSIONS: The questionnaire reliability was found to be satisfactory in the population studied.