Physical activity measurement in people with spinal cord injury: comparison of accelerometry and self-report (the Physical Activity Recall Assessment for People with Spinal Cord Injury).

Purpose: To (1) evaluate the level of agreement between individually calibrated accelerometers and the self-reported Physical Activity Recall Assessment for People with Spinal Cord Injury when assessing moderate-vigorous physical activity; and (2) qualitatively examine the different components of physical activity each measure assesses.Materials/methods: Nineteen manual wheelchair users with chronic spinal cord injury (19.0 ± 12.9 years post injury, C5-L2 injury level) wore a wrist and spoke accelerometer for one week then returned to the lab and completed the Physical Activity Recall Assessment for People with Spinal Cord Injury for their last 3 days of accelerometer wear.Results: Bland-Altman plots revealed low levels of agreement between the two measures when measuring total (bias = -5.6 ± 70.41 min/d, 95% agreement limits = -143.6-132.4 min/d), wheeled (bias = -9.7 ± 30.2 min/d, 95% agreement limits = -69.0-49.5 min/d), and non-wheeled (bias =12.3 ± 53.8 min/d, 95% agreement limits = -93.1-117.6 min/d) moderate-vigorous physical activity. The accelerometer was beneficial for detecting intermittent or brief activities while the self-report measure was useful for measuring lifting activities (e.g., resistance training) and wheeling on inclined surfaces.Conclusion: Total and wheeled moderate-vigorous physical activity measured by an accelerometer and a self-report measure showed low agreement at the individual level. Additional research is needed to examine whether physical activity may be best measured using accelerometers and a self-report measure concurrently.Implications for RehabilitationAccurate physical activity measurement has important implications for understanding the relationship between physical activity and health outcomes.Many limitations exist to accurately measuring physical activity in people with spinal cord injury.The most commonly used measures of physical activity in spinal cord injury are accelerometers and the self-reported Physical Activity Recall Assessment for People with Spinal Cord Injury.Accelerometers and the Physical Activity Recall Assessment for People with Spinal Cord Injury show low levels of agreement, highlighting that there are differences in the specific physical activity patterns that each measure is able to capture.