RESUMEN
OBJECTIVES: The purpose of this study was to translate and investigate the validity and reliability of the modified Baecke Physical Activity Questionnaire (mBQ) in the Greek adult population. STUDY DESIGN: This is a cross-cultural study. METHODS: The cross-cultural adaptation of the mBQ was performed according to official guidelines. The prefinal Greek translation was tested in 30 healthy participants. The reliability was determined (n = 100) by filling out the mBQ, two times, 1 week apart. For validation (n = 45), the scores between the mBQ and the International Physical Activity Questionnaire (IPAQ) were compared, and the correlation between mBQ and VO2max and between mBQ and interview (METS) were assessed. RESULTS: High statistical significant of test-retest reliability was found (intraclass correlation coefficient = 0.84; standard error of measurement = 0.48; smallest detectable difference = 16.7%; Cronbach's alpha = 0.92). Statistical significant correlation between the mBQ and the IPAQ (r = 0.425, P = 0.005), high correlation between the mBQ and METS (r = 0.691, P = 0.000), and moderate correlation between mBQ and VO2max (r = 0.388, P = 0.08) were found. CONCLUSION: The Greek mBQ was found to be reliable and valid for assessing the level of physical activity in the Greek population. CLINICALTRIALS. GOV IDENTIFIER: NCT04890756.