Rasch Model Analysis: Validity and Reliability of Body Image Instrumen for Adolescent Prisoners

Body image can be seen as a multifaceted concept that includes an individual's conscious understanding of their physical appearance, involving thoughts and emotions that arise from that perception. The distress that arises in adolescents is triggered by physical changes that cause dissatisfaction with themselves. Feelings of dissatisfaction indicate that adolescents reject their bodies. It seems very important to understand adolescents' perceptions and feelings towards their bodies by measuring body image variables. This study aims to analyze the validity and reliability of the body image instrument using the Rasch Model analysis. This study used a survey method with a cross-sectional study design that was analyzed through the Rasch Model using the Winstep Application version 3.73. The participants in this study were 135 juvenile inmates. The result of Pearson Reliability is 0.57 and Item Reliability is 0.84. This shows that the consistency of respondents' answers is still weak, but the quality of the items is included in the excellent category. Based on the criteria for the level of fit of the items, all items on the body image instrument are proven to be fit, because they have met at least one of the three criteria with the Rasch model. This indicates that there are no unfit items on the body image instrument. This shows that the instrument used is included in the excellent category.