Comparison of Self-Report Versus Sensor-Based Methods for Measuring the Amount of Upper Limb Activity Outside the Clinic

Objective: To compare self-reported with sensor-measured upper limb (UL) performance in daily life for individuals with chronic (≥6mo) UL paresis poststroke. Design: Secondary analysis of participants enrolled in a phase II randomized, parallel, dose-response UL movement trial. This analysis compared the accuracy and consistency between self-reported UL performance and sensor-measured UL performance at baseline and immediately post an 8-week intensive UL task-specific intervention. Setting: Outpatient rehabilitation. Participants: Community-dwelling individuals with chronic (≥6mo) UL paresis poststroke (N=64). Interventions: Not applicable. Main Outcome Measures: Motor Activity Log amount of use scale and the sensor-derived use ratio from wrist-worn accelerometers. Results: There was a high degree of variability between self-reported UL performance and the sensor-derived use ratio. Using sensor-based values as a reference, 3 distinct categories were identified: accurate reporters (reporting difference ±0.1), overreporters (difference >0.1), and underreporters (difference <−0.1). Five of 64 participants accurately self-reported UL performance at baseline and postintervention. Over half of participants (52%) switched categories from pre-to postintervention (eg, moved from underreporting preintervention to overreporting postintervention). For the consistent reporters, no participant characteristics were found to influence whether someone over- or underreported performance compared with sensor-based assessment. Conclusions: Participants did not consistently or accurately self-report UL performance when compared with the sensor-derived use ratio. Although self-report and sensor-based assessments are moderately associated and appear similar conceptually, these results suggest self-reported UL performance is often not consistent with sensor-measured performance and the measures cannot be used interchangeably.