Development and psychometric validation of a scoring questionnaire to assess healthy lifestyles among adolescents in Catalonia.

BACKGROUND Lifestyle is intimately related to health. A questionnaire that specifically scores the healthiness of lifestyle of Catalan adolescents is needed. The objective of this study was to develop and validate a scoring questionnaire called VISA-TEEN to assess the healthy lifestyle of young Catalans that can be answered quickly and user-friendly. METHODS A lifestyle questionnaire was developed based on the analysis of contributions from two focus groups, one with adolescents and the other with people who work with them (teachers and doctors). A panel of experts validated the content of items that were ultimately selected for the VISA-TEEN questionnaire. Three hundred ninety-six adolescents (215 boys and 181 girls, age = 13-19 years) completed the VISA-TEEN. Internal consistency was assessed using Cronbach's alpha (α) reliability coefficient. Test-retest reliability, using an intraclass correlation coefficient (ICC), was calculated based on scores attained two weeks apart. Construct validity was assessed by the extraction of components with an exploratory factor analysis. The relationship between the scores was measured using the health-related quality of life (HRQoL) KIDSCREEN-10 Index (the relationship was assessed by calculating Pearson's r correlation coefficient). The association of scores in the VISA-TEEN for self-rated health (SRH) was also examined by executing an analysis of variance (ANOVA) between the different categories of this variable. We also calculated the index of fit for factor scales (IFFS) for each component, as well as the discriminatory power of the instrument using Ferguson's δ (delta) coefficient. RESULTS The VISA-TEEN questionnaire showed acceptable reliability (α = 0.66, αest = 0.77) and a very good test-retest agreement (ICC = 0.860). It could be broken down into the following five components, all with an acceptable or very good IFFS (0.7-0.96): diet, substance abuse, physical activity, Rational Use of Technological Leisure (RUTL), and hygiene. Scores on the VISA-TEEN showed significant correlation with the KIDSCREEN index (r = 0.21, p < 0.001) and were associated with SRH (p < 0.001). The discriminatory power was found to be δ = 0.97. CONCLUSIONS The VISA-TEEN questionnaire developed to study the lifestyle of Catalan adolescents is a valid instrument to apply in this population as it is shown in the present psychometric tests to understand the role of lifestyle in the health of teenagers or to test the efficacy of health campaigns intended to improve teenagers' lifestyle.