Repeated single-limb postural stability testing elicits a practice effect

ObjectiveTo document the effects of repeated testing on the single-leg stance balance task.DesignSingle cohort repeated measures.SettingLaboratory in an educational institution.SubjectsThirty-two healthy males and females.Outcome measureThe number of errors (deviations from the required posture) during each 20-s trial summed over the eight conditions recorded on six occasions.ResultsThere was a statistically significant (p=.0013) decrease in the number of errors recorded over the six sessions, from 26.8 (95% CI: 23.1–30.5) to 19.7 (95% CI: 16.3–23.1). Linear regression confirmed a systematic decrease of 1.5 errors per session on average (95% CI: 1.0–1.9; p<.0001).ConclusionThe decreased number of errors (increased performance) with repeated testing alerts clinicians to the need for care when using this test protocol to measure rehabilitation interventions.