Translation of the short version of the Smartphone Addiction Scale into Brazilian Portuguese: cross-cultural adaptation and testing of measurement properties

Background: Smartphone use has been constantly increasing. Smartphone addiction can lead to changes in the emotional state and musculoskeletal system of users. To identify smartphone addicts, the Smartphone Addiction Scale-Short Version was developed; however, this scale has not been translated into Brazilian Portuguese and tested for its measurement properties. Objective: To translate and cross-culturally adapt the Smartphone Addiction Scale-Short Version into Brazilian Portuguese; to assess the internal consistency, reliability and construct validity of the scale among university students. Methods: The cross-cultural adaptation was performed following the guidelines for cross-cultural adaptation of self-report measures, and data were collected via online surveys administered to 59 university students over 18 years of age for test-retest. To test the measurement properties of the final version of the Smartphone Addiction Scale-Short Version, a convenience sample including 130 university students was used. Results: The Smartphone Addiction Scale-Short Version showed good reliability for test-retest scores (ICC3,1 = 0.82; 95% CI = 0.70-0.89) and good internal consistency considering all 10 items (Cronbach's alpha = 0.95). The construct validity was calculated comparing the Smartphone Addiction Scale-Short Version score to data from a questionnaire prepared by the authors of this study, including frequency per day (r = 0.35; p < 0.001), leisure time on the smartphone (r = 0.33; p < 0.001), and time working on the smartphone (r = 0.18; p = 0.04) that were significantly positively associated with higher Smartphone Addiction Scale-Short Version scores. The results show a high prevalence of smartphone addiction among university students (33.1%). Conclusion: It can be concluded that the Brazilian Portuguese version of the Smartphone Addiction Scale-Short Version is a reliable and valid tool for screening smartphone addiction in university students. (C) 2018 Associacao Brasileira de Pesquisa e Pos-Graduacao em Fisioterapia. Published by Elsevier Editora Ltda. All rights reserved.