Reliability and Validity of Common Subjective Instruments in Assessing Physical Activity and Sedentary Behaviour in...

The reliability and validity of common physical activity (PA) questionnaires are not well investigated in college students. This study aims to evaluate the reliability and validity of common subjective instruments in measuring PA and sedentary behaviour (SB) among college students. A total of 142 college students were included through convenience sampling. Each participant was asked to wear Actigraph wGT3X-BT accelerometers and fill physical activity logs (PAL) for 7 consecutive days. The Global Physical Activity Questionnaire (GPAQ), the International Physical Activity Questionnaire long-form (IPAQ-LF), and short-form (IPAQ-SF) were interviewed by face-to-face at both day 0 and day 8. Reliability was evaluated by intraclass correlation coefficient (ICC), while the validity was evaluated by Spearman correlation coefficient and Bland-Altman statistics. The instruments showed moderate reliability in reporting total PA (ICC = 0.50-0.62) and SB (ICC = 0.47-0.52), while moderate validity in reporting moderate and vigorous PA (MVPA) (r = 0.37-0.42), but fair to poor validity in reporting SB (r = 0.09-0.28). Bland-Altman plots showed that all the instruments would underestimate MVPA and overestimate SB. Thus, in Chinese younger adults, the GPAQ, IPAQ-LF, IPAQ-SF, and PAL provide limited but acceptable reliability and validity in measuring MVPA and SB, among which GPAQ might be the most valid instrument.