Reliability and validity of the German language version of Girls' Disinclination for Physical Activity Scale.

The high prevalence of insufficient physical activity (PA) among adolescents is an important public health issue. Studying reasons for disliking PA might help researchers better understand its underlying mechanisms, yet this psychological construct has been understudied. This study established the psychometric properties of the German language version of the Girls' Disinclination for Physical Activity Scale (G-DAS-Ger). Data were collected on a sample of 257 adolescent girls in Austria (mean age: 13.0 ± 0.7 years) using the G-DAS-Ger and the Physical Activity Enjoyment Scale. One week after the first assessment, the questionnaires were re-administered to 78 girls. Between two administrations, PA of 215 girls was monitored for seven consecutive days using the ActiGraph GT3X+ accelerometers. Confirmatory factor analysis of G-DAS-Ger showed good fit for a three-factor model (χ(2)/df = 2.025; Bollen-Stine (B-S) p = 0.159; root mean square error of approximation = 0.063; standardised root mean square residual = 0.054; comparative fit index = 0.950). Cronbach's alphas for G-DAS-Ger factors/subscales ranged 0.64-0.76. The test-retest reliability assessed by Spearman's rank correlation ranged 0.62-0.75. Only one subscale correlated significantly with vigorous-intensity PA (Spearman's rho = -0.16) and none with moderate-to-vigorous-intensity PA, which indicated poor predictive validity of the G-DAS-Ger. Correlations between G-DAS-Ger subscales and enjoyment of PA ranged from -0.29 to -0.41, indicating satisfactory convergent validity. The G-DAS-Ger may be used in its present form to assess disinclination for PA among adolescent girls in German-speaking countries. However, our results put into question the stability of the originally proposed factor structure of the questionnaire and its predictive validity among German-speaking adolescent girls. Methodological refinements to the G-DAS-Ger may be required to improve its psychometric properties in this population.