Translation, Cultural Adaptation, and Evaluation of the Psychometric Properties of the Greek Version of the Rapid Weight Loss Questionnaire for Combat Sports Athletes

Abstract

Rapid weight loss (RWL) is commonly practiced among combat sports athletes to reduce body mass before competition. The Rapid Weight Loss Questionnaire (RWLQ) is a self-report instrument designed to assess weight loss behaviors and practices. This study aimed to translate and culturally adapt the RWLQ into Greek (RWLQ-GR), evaluate its psychometric properties, and examine the prevalence, magnitude, and methods of RWL among Greek-speaking combat sports athletes. The translation and cultural adaptation process followed established international guidelines. Measurement properties were examined in terms of test–retest reliability, known-groups and convergent validity. A total of 209 Greek-speaking combat sports athletes were included in the final analysis, of whom 34 completed the questionnaire twice for the test–retest reliability assessment. Overall, 92% of participants reported engaging in weight loss before competition, with a median body mass reduction of 4.5%. The RWLQ-GR demonstrated high test–retest reliability for numerical items and total score. Categorical items showed fair to excellent reliability. No systematic differences were observed between repeated administrations of the questionnaire. The questionnaire differentiated athletes according to their usual weight loss, providing supportive evidence for known-group validity. Evidence of convergent validity was limited: the RWLQ-GR total score was not associated with the EAT-26 total score and correlated weakly with the Bulimia and Food Preoccupation subscale only. Overall, these findings support the use of the RWLQ-GR for the assessment and surveillance of self-reported RWL behaviors in Greek-speaking combat sports athletes.