Moderate reliability of the lateral step down test amongst experienced and novice physical therapists

BACKGROUND/INTRODUCTION: The lateral step-down test is used to appraise movement quality in patients with patellofemoral pain (PFP), however, it is unclear if reliability of the test is affected by physical therapist experience. OBJECTIVE: Determine if there is a difference in reliability between ‘experienced’ and ‘novice’ physical therapists appraising movement quality of patients with PFP during the lateral step-down test. METHODS: Three ‘experienced’ and 3 ‘novice’ physical therapists analyzed movement quality of 22 participants [mean age (SD) 28.25 (6.5) years] with PFP. Physical therapists viewed two-dimensional videos of participants performing the lateral step-down test and appraised the quality with a score (0–1 = ‘good’; 2–3 = ‘fair’, and 4–5 = ‘poor’) at baseline and 1 week. Inter- and intra-rater reliability were calculated with kappa and percent agreement. Differences between the groups were assessed with the chi-square test with an a priori alpha level of < 0.05. RESULTS: Inter- and intra-rater reliability ranged from fair to moderate (κ = 0.40–0.65). There was no difference in reliability between ‘experienced’ and ‘novice’ physical therapists at baseline (p = .13) or 1 week post testing (p = .94). CONCLUSIONS: There was no difference in reliability between ‘experienced’ and ‘novice’ physical therapists using categories to appraise movement quality during the lateral step-down test for patients with chronic PFP.