Test-retest reliability and internal structure of the Brazilian version of the impact on participation and autonomy (IPA-Br4) for individuals with physical disabilities

Background: Participation is considered a central outcome of rehabilitation and needs to be appropriately assessed from a perspective that values individual values and preferences. The Brazilian version of the Impact on Participation and Autonomy (IPA-Br4) is the only adequate instrument to assess participation from a subjective perspective in Brazil.

Objective: To investigate the test-retest reliability and internal structure (structural validity and internal consistency) of the digital version of IPA-Br4 for individuals with physical disabilities.

Methods: Test-retest reliability was assessed with Intraclass Correlation Coefficients (ICC), structural validity with Confirmatory Factor Analysis (CFA), and internal consistency with Cronbach α.

Results: Thirty (43.25 ± 10.6 years old, 63.3% female) and 130 (47.51 ± 15.73 years old, 58.5% male) individuals participated in the test-retest reliability and structural validity assessments, respectively. ICCs for each domain were: Autonomy indoors = 0.84; Family role = 0.87; Social life and relationships = 0.87; Autonomy outdoors = 0.84. The CFA model for four factors showed appropriate fit with factor loadings indicating that all items loaded onto their respective factors, with magnitudes > 0.30 (p < 0.05). All Cronbach α values (internal consistency) were above 0.82.

Conclusion: The digital version of IPA-Br4 has adequate test-retest reliability and internal structure to be used with adults with physical disabilities.