Poor Agreement between Responses to the International Physical Activity Questionnaire and Objective ActiGraph ® Data among Persons with Major Depressive or Bipolar Disorders.

The purpose of this research was to investigate the degree of agreement between data from the International Physical Activity Questionnaire-Short Form (IPAQ) and accelerometer (ActiGraph ® ) readings for physical activity (PA), classified as moderate, vigorous, and moderate-vigorous PA, and sedentary behavior (SB) in participants with major depressive or bipolar disorder. Following a cross-sectional observational design ( n = 30), participants used an accelerometer for 4 to 7 days (minimum of 10 h per day) and answered the IPAQ (for the same period as accelerometer use). Our results suggest significant differences ( p < 0.05) when comparing the ActiGraph ® and IPAQ data: for moderate PA, 155 min vs. 25 min per week; for moderate-vigorous PA, 157 min vs. 50 min per week; and for SB, 8 h vs. 3 h per day. Spearman's correlation coefficients (ActiGraph ® and IPAQ) were low for moderate PA, vigorous PA, and moderate-vigorous PA (rho = 0.03 to 0.13). The Bland-Altman plot showed a bias of -75 min for moderate PA, 9 min for vigorous PA, -66 min for moderate-vigorous PA, and -5 h for SB. Considering the differences observed and the objectivity of the ActiGraph ® measurements, whenever possible, we recommend ActiGraph ® measurements of PA and SB for these clinical groups.