TY - JOUR T1 - Validity and reproducibility of a physical activity questionnaire for elderly JF - European Respiratory Journal JO - Eur Respir J VL - 38 IS - Suppl 55 SP - p4617 AU - Lara Siebeling AU - Sarah Wiebers AU - Leo Beem AU - Milo Puhan AU - Gerben ter Riet Y1 - 2011/09/01 UR - http://erj.ersjournals.com/content/38/Suppl_55/p4617.abstract N2 - Background: Physical activity is important for elderly to maintain their health and functional ability. It helps predict the course of chronic diseases. Many existing questionnaires have not been compared to activity monitors. We examined validity and reproducibility of the LASA Physical Activity Questionnaire (Lapaq) against an accelerometer in Dutch elderly (65+).Methods: Participants wore the accelerometer for two weeks and filled in Lapaq twice. We examined validity using correlation coefficients, histograms and modified Bland-Altman plots. We used logistic regression to assess how well Lapaq discriminates between persons whose activity level is or is not in accordance with recommendations from the American College of Sports Medicine and the American Heart Association. Intraclass correlation coefficients (ICC) were used to examine reproducibility.Results: 89 persons were included, 48% men, median age 73 and median BMI 25. 36%, 43%, and 22% had no, one, or 2+ chronic diseases. As a reference, two full weeks contain 20160 minutes (336h). The total duration of activity in two weeks was 2439 (Lapaq T1), 1994 (Lapaq T2) and 2788 minutes (accelerometer). The difference between Lapaq T1 and accelerometer was 510 minutes (8.5 hours). The Pearson correlation coefficient was 0.34 (95% CI 0.13-0.51). The I.C.C. was 0.68 (95% CI 0.56-0.79). The area under the curve is 0.73 (95% CI 0.59 - 0.86).Conclusions: Due to moderate reproducibility and low validity, Lapaq seems unsuitable for exact measurement of physical activity in elderly. If the more modest aim is to determine if a person's activity level is above the recommendation level, Lapaq classifies around 73% correctly. ER -