The International Physical Activity Questionnaire modified for the elderly: aspects of validity and feasibility

Objective: To modify the self-administered, short version of the International Physical Activity Questionnaire (IPAQ) for adults to be used in the elderly (aged 65 years and above), and to validate this modified IPAQ for the elderly (IPAQ-E). Design: A direct validity study using accelerometer-measured physical activity (PA) as the criterion measure, and an indirect criterion validity study using high-sensitivity C-reactive protein (hs-CRP) as a biological marker of activity. Setting: Organisations for retired persons in Sweden. Subjects: The direct validity study consisted of fifty-four participants and the indirect criterion validity study consisted of 359 participants. All participants were retired persons (66-91 years) living independently. Results: All self-reported activity domains (sitting, walking, moderate and vigorous) were positively correlated with the corresponding variable objectively assessed by an accelerometer (rho = 0.277-0.471), but a systematic error was observed. The specificity of IPAQ-E to identify low-active participants was 85 %, and the sensitivity to identify the more active participants was 81 %. A main effect of IPAQ-E category (Low, Moderate or High) was observed for hs-CRP (P = 0.041). Conclusions: We found this modified version of IPAQ, the IPAQ-E, to be well accepted by our sample of socially active elderly. It provided acceptable estimates of PA, well in line with other questionnaires, even though it had a systematic error. The IPAQ-E was able to identify an expected response of a biomarker (hs-CRP) to PA. We recommend the use of the IPAQ-E to classify participants aged 65 years and above into PA categories, to rank individuals or to identify individuals meeting certain PA criteria.