Developing a brief older adults' physical activity questionnaire.

Aim: This study aimed to develop and evaluate the Brief Older Adults' Physical Activity Questionnaire (BOPAQ), which was designed to quickly assess moderate-to-vigorous physical activity (MVPA) in community-dwelling older adults.

Methods: We used a cross-sectional study design involving 165 older participants. The BOPAQ calculated weekly MVPA duration based on two questions regarding the number of days per week engaged in MVPA and the daily duration of activity. Validity was assessed by correlating the MVPA durations derived from the BOPAQ with those obtained from the ActiGraph and International Physical Activity Questionnaire short form. Reliability was evaluated using the intraclass correlation coefficient, and measurement errors were analyzed using Bland-Altman plots.

Results: The BOPAQ reasonably correlated with accelerometer-based MVPA (rho = 0.297) and showed good test-retest reliability (intraclass correlation coefficient of 0.78, 95% CI 0.64-0.87). In contrast, the correlation between the International Physical Activity Questionnaire short form and accelerometer-based MVPA was poor (rho = 0.139). The cut-off value for the BOPAQ was set to identify participants engaging in <150 min of objectively measured physical activity per week, corresponding to the 150-min threshold. However, the area under the curve in the receiver operating characteristic analyses was not significantly high (0.601, 95% CI 0.514-0.688). The Bland-Altman plots showed an underestimation bias of 51.72 min/week (95% CI 1.61-101.84) and showed heteroscedasticity.

Conclusion: Despite some measurement errors, the BOPAQ is an available tool for assessing MVPA in community-dwelling older adults. Geriatr Gerontol Int 2024; ••: ••-••.