Translation, adaptation and validation of the “Measure of older adults sedentary time” questionnaire in Brazilian older adults

Abstract Modern lifestyle is associated with prolonged exposure to sedentary behavior (SB), especially in older adults; however, there is a lack of validated questionnaires to measure SB in Brazilian older adults. The aim of this study was to adapt and validate the Brazilian version of the "Measure of Older Adults Sedentary Time" (MOST) questionnaire in Brazilian older adults. Content validity, clarity and concurrent validity of the adapted MOST were examined. Fifty-seven participants (68.7 ± 3.47 years) answered the adapted version of the MOST questionnaire and wore an ActiGraph wGT3X-BT accelerometer for seven days. After this period, participants answered the adapted MOST again and the accelerometer was collected. MOST answers were summed over for calculating self-reported time spent in SB. A cutoff point of < 100 counts/min was applied to accelerometer data for estimating time spent in SB. The relationship between SB estimates from MOST and accelerometer was verified by Pearson correlation, reproducibility was verified by intra-class correlation coefficient (ICC), internal consistency by Cronbach's alpha (α) and concordance by Bland-Altman. Significance was set at P <0.05. Content validity index and clarity index were 100% and 98%, respectively. ICC was 0.72 (95% CI: 0.56-0.82) for total time in SB assessed with the MOST questionnaire. The correlation between SB estimates from MOST and accelerometer data was 0.37 (95% CI: 0.13-0.58). The adapted MOST systematically underestimated SB compared to accelerometer (measurement bias: -732.8 min/week [2087.6; -3553.2 min/wk]). The adapted MOST questionnaire presents adequate validity for assessing SB in the Brazilian older adults.