Validity and Reliability of the Turkish Dynamic Gait Index in Dyslexic Children

Abstract

This study investigated the psychometric properties of the Turkish version of the Dynamic Gait Index (DGI) in dyslexic children. Sixty children aged 8–14 years were included. The original English DGI was translated into Turkish and cross-culturally adapted following standard guidelines. To evaluate its measurement properties, two independent raters assessed all children in a single session, and one of them repeated the evaluation after 7 days. Internal consistency was determined via Cronbach’s alpha, while intra- and inter-rater reliability were assessed using Intraclass Correlation Coefficients (ICC). We found the internal consistency of the DGI to be moderate, with a Cronbach’s alpha of 0.624, and it demonstrated good intra-rater (ICC = 0.85) and inter-rater (ICC = 0.83) reliability. Concurrent validity was examined by correlating DGI scores with the Timed Up and Go Test (TUG) and the Functional Reach Test (FRT) results using Spearman’s correlation analysis. However, no significant correlations were found between DGI scores and TUG or FRT performance (p > 0.05). This pattern may be related to ceiling effects and the limited sensitivity of these tests to subtle gait and dynamic balance impairments in dyslexic children. Notably, dyslexic children scored significantly lower on the DGI and performed worse on the TUG compared with their non-dyslexic peers (DGI: p < 0.001; TUG: p = 0.035), whereas no significant difference was observed for FRT scores (p = 0.43). These findings indicate that the Turkish DGI shows good intra- and inter-rater reliability in dyslexic children, but that evidence for its concurrent validity with clinical balance tests (TUG and FRT) is limited. Further research is needed to identify complementary assessment tools that can provide a more comprehensive evaluation of balance in this population.