Measuring Physical Activity in Children with Pedometers: Reliability, Reactivity, and Replacement of Missing Data

Abstract

The study was undertaken to evaluate (a) the reliability of pedometer data and reactivity of children to wearing a pedometer, (b) the effectiveness of a missing data replacement procedure, and (c) the validity of the Leisure Time Exercise Questionnaire (LTEQ). Six days of pedometer data were collected from 299 middle-school children, followed by administration of the LTEQ. Six days of pedometer data were found to be adequately reliable for research into habitual physical activity ( R xx = .79) and no reactivity occurred. Inclusion of weekday and weekend scores is recommended where possible. The individual-centered data-replacement procedure did not adversely affect reliability, so this data-replacement method offers great promise to physical activity researchers who wish to maintain statistical power in their studies. The LTEQ does not appear to measure physical activity similarly to pedometers ( r = .05), and researchers should use the LTEQ with caution in children until further research explains this discrepancy.