Item response modeling: a psychometric assessment of the children’s fruit vegetable water and physical activity self-efficacy scales among Chinese children

摘要

BackgroundThis study aimed to evaluate the psychometric properties of four self-efficacy scales (i.e., self-efficacy for fruit (FSE), vegetable (VSE), and water (WSE) intakes, and physical activity (PASE)) and to investigate their differences in item functioning across sex, age, and body weight status groups using item response modeling (IRM) and differential item functioning (DIF).