Convergent Validity of a Physical Activity Questionnaire against Objectively Measured Physical Activity in Adults : The Cardiovascular Risk in Young Finns Study

摘要

Background: Traditionally, a self-reported questionnaire has been acost-effective method of gathering information about physical activity (PA).An objective measurement, such as the use of a pedometer, can be used to validatethe findings of a PA questionnaire in a large population. Objective: Thestudy objective was to determine the convergent validity of a PA questionnaireagainst objectively measured PA in adults obtained with the use of apedometer. Methods: Data from the Cardiovascular Risk in Young FinnsStudy (YFS) were collected from 1853 participants aged 30 - 45 years. Theparticipants completed a self-reported questionnaire that included items onleisure time, commuting and habitual PA. PA was expressed as leisure-timephysical activity index (PAI) and metabolic equivalent hours/week (METh/wk).The participants wore a pedometer for seven consecutive days and used it torecord their total daily and aerobic steps. Results: There was a low to moderateassociation between the self-reported questionnaire and pedometermeasurements regarding both total steps and aerobic steps taken during leisuretime and commuting PA. An association was not observed between pedometer data and habitual PA. Of the individual items in the questionnaire,questions that described the frequency of PA and the duration of vigorous PAcorrelated the most strongly with the pedometer values obtained for total andaerobic steps (r = 0.28 - 0.44, p ≤ 0.010). Conclusions: These findings suggestthat the YFS PA questionnaire showed acceptable convergent validity in assessing,in particular, exercise-type PA in an adult population.