Validation and reliability of the Persian version of Gillette functional assessment questionnaire in patients with cerebral palsy.

Purpose: This research aimed to evaluate the content, concurrent validity and test-retest reliability of The Gillette Functional Assessment Questionnaire (FAQ) for assessing functional mobility in children and adolescents with cerebral palsy (CP).

Materials and methods: The Persian FAQ were translated and verified according to international standards. To assess concurrent validity, Spearman's coefficient was used to correlate the FAQ scores with the Gross Motor Function Classification System (GMFCS) levels and Functional Mobility Scale (FMS) ratings of 148 participants. In addition, test-retest reliability was evaluated among 30 participants by calculating weighted kappa coefficients.

Results: The study demonstrated almost perfect test-retest reliability (κw = 0.836, p < 0.001) and strong concurrent validity. Spearman correlation coefficients between the FAQ and GMFCS were -0.913, while correlations between the FAQ and FMS were calculated separately for each of the three FMS distances, ranging from 0.880 to 0.914 (p < 0.001).

Conclusions: These findings confirm the validity and reliability of the Persian FAQ in assessing functional mobility across diverse settings for children with CP. The Persian FAQ proves to be a valuable tool for clinicians and researchers in understanding and addressing functional mobility challenges in children with CP.