Criterion validity of the Saltin-Grimby Physical Activity Level Scale in adolescents. The Fit Futures Study
Background The Saltin-Grimby Physical Activity Level Scale (SGPALS) is commonly used to measure physical activity (PA) in population studies, but its validity in adolescents is unknown. This study aimed to assess the criterion validity of the SGPALS against accelerometry in a large sample of adolescents. A secondary aim was to examine the validity across strata of sex, body mass index (BMI), parental educational level, study program and self-reported health. Methods The study is based on data from 572 adolescents aged 15–17 years who participated in the Fit Futures Study 2010–11 in Northern Norway. The participants were invited to wear an accelerometer (GT3X) attached to their hip for seve…