Validation of a Self-Discipline Questionnaire for Athletes

This study aims to modify and validate a self-discipline questionnaire for application among athletes in Indonesia. The questionnaire was adapted from the self-discipline scale originally developed by Sal (2022) for university students. This study employed a quantitative research design using a factor analysis approach. The population consisted of coaches and athletes from Central Java Province, representing three types of sports: individual, team, and combat sports. The sample included 30 coaches for the validity test and 265 athletes selected through purposive sampling, based on the criteria of being active athletes and having achieved at least a regional championship. These athletes were then subjected to Exploratory Factor Analysis (EFA). The findings identified two self-discipline dimensions for athletes in Indonesia: Training in a Plan (TIP) and Attention (ATTN). The results of the validity test using Aiken’s V indicated that each item scored above 0.8. The EFA results showed a KMO-MSA value of 0.691 (>0.50) and a significant Bartlett’s Test of Sphericity (p < 0.001). Additionally, the anti-image correlation, communalities, and rotated component matrix revealed factor loadings above 0.50 for all 18 indicator items. Therefore, the modified self-discipline questionnaire for Indonesian athletes demonstrates validity and high factor loadings for each indicator. Future studies are encouraged to expand the sample and include athletes from various provinces across Indonesia, as well as to incorporate more complex analytical methods, which could enhance the questionnaire’s reliability and credibility.