Validity and Reliability of a Single Question for Leisure-Time Physical Activity Assessment in Middle-Aged Women.

Purpose: To investigate the validity and test-retest reliability of a single seven-level scale physical activity assessment question (SR-PA L7) and its three-level categorization (SR-PA C3).

Methods: The associations of SR-PA L7 and C3 with accelerometer-measured leisure-time physical activity (ACC-LTPA) and with the results of four different physical performance tests (6-min walk [n = 733], knee extension [n = 695], vertical jump [n = 731], and grip force [n = 780]) were investigated among women aged 47-55 years participating in the Estrogenic Regulation of Muscle Apoptosis study (n = 795). The reliability was studied using Spearman correlations with 4-month test-retest period (n = 152).

Results: SR-PA L7 and C3 had low correlations with ACC-LTPA (rs = .105-.337). SR-PA L7, SR-PA C3, and ACC-LTPA explained comparable but small amount of variance of the physical performance test results. The reliability analysis provided moderate agreement (rs = .707 and .622 for SR-PA L7 and C3, respectively).

Conclusions: SR-PA L7 and C3 demonstrated limited validity and reasonable repeatability.