Inter-rater reliability and construct validity of a cross-diagnostic movement quality score for rehabilitation assessment.

OBJECTIVE: To examine the inter-rater reliability and construct validity of a Movement Quality Score (MQS) within the Standard Physical Therapy Assessment (SPTA) across diagnostic groups. DESIGN: Cross-sectional study. SUBJECTS AND METHODS: Eighty-four hospitalized patients undergoing rehabilitation for neurological, musculoskeletal, or internal medical conditions were included. Inter-rater reliability was assessed in 68 participants independently evaluated by 2 physiotherapists. The MQS was scored using the SPTA component. Inter-rater reliability of the summed score was analysed using the intraclass correlation coefficient (ICC [2,1]). Construct validity was examined using Spearman's rank correlations between the MQS and the Functional Independence Measure (FIM) motor total score and its subdomains (self-care, sphincter control, transfers, and locomotion), as well as other SPTA components. RESULTS: The MQS demonstrated excellent inter-rater reliability (ICC [2,1] = 0.93). It showed a very strong correlation with the FIM motor total score (ρ = 0.91, p < 0.001), with strong associations for transfers and locomotion (ρ = 0.92) and self-care (ρ = 0.86). The correlation with sphincter control was lower (ρ = 0.68). CONCLUSION: The MQS demonstrates excellent reliability and strong construct validity, supporting its use as a movement-focused complement to activities of daily living-based assessments in heterogeneous rehabilitation populations.