Development of the Persian Version of Gross Motor Function Measure-88 (GMFM-88): A Study of Reliability

The aims of this study were to cross-culturally translate and equivalence of the Gross Motor Function Measure 88 (GMFM-88) in to Persian and to evaluate its reliability in 50 children with Cerebral Palsy (CP). Our investigation was a none-experimental and methodological study which developed a Persian translation of the GMFM-88 based on International Quality of Life Assessment (IQLA) guidelines. Inter-rater reliability was performed by comparison of scores recorded by two expert physiotherapists in a blind pattern while inter-rater reliability was assessed by comparison of scores recorded by an expert physiotherapist in two continuous weeks. Intra-class Correlation Coefficient (ICC) was used to evaluate both reliabilities. Additionally internal consistency was calculated using Cronbach's alpha coefficient. The ICC was 0.99 for both inter-rater reliability and intra-rater reliability with 95% Confidence Interval (CI) = 0.99-1. Cronbach’s alpha coefficients for all dimensions of the GMFM-88 were ranged 0.78-0.94, which showed an acceptable internal consistency. The Persian version of the GMFM-88 which indicated high internal consistency is a reliable instrument to quantify gross motor function in children with CP and to follow efficacy of various rehabilitation and medical treatments in these patients.