Portuguese version of the Quality of Life Enjoyment and Satisfaction Questionnaire: a validation study

Abstract

The aim of this study was to demonstrate the validity and reliability of the Portuguese version of the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q) among substance users in southern Brazil. The original English version of the Q-LES-Q was translated into Portuguese taking into account semantic and conceptual equivalence. The Portuguese versions of the Q-LES-Q and the World Health Organization Quality of Life Instrument (WHOQOL-BREF) were used to assess quality of life among crack cocaine and inhalant users. Factorial and reliability analyses as well as correlation studies were conducted to establish the psychometric properties of the Portuguese version of the Q-LES-Q. All areas of the Q-LES-Q achieved significant Cronbach's coefficients. Significant Pearson correlation coefficients were obtained between various subscales of the Q-LES-Q and the four dimensions of the WHOQOL-BREF. Correlations were significant when crack and inhalant users were analyzed separately or conjointly. Inhalant users presented significantly higher scores than crack users in the social (p=0.035) and general (p=0.005) subscales of the Q-LES-Q. The Portuguese version of the Q-LES-Q possesses sound internal validity. The English version of the Q-LES-Q was adequately adapted to Portuguese. Inhalant users may present lower levels of satisfaction with social life and overall quality of life than crack users. The Portuguese version of the Q-LES-Q is a reliable questionnaire for future research and clinical use with substance users in Brazil.