Inter-rater Reliability, Test-retest Reliability, and Internal Consistency of the Persian Version of Dynamic Gait Index in Patients With Multiple Sclerosis

Abstract

Introduction: Dynamic Gait Index (DGI) has been used as a valid and reliable tool to assess balance performance in various populations. However, it has been translated into the Persian language and has shown perfect psychometric properties in the elderly population. The Persian version in Multiple Sclerosis (MS) population was validated, but its reliability has not been examined. The aim of the current study was to investigate the inter-rater reliability, test-retest reliability, and internal consistency of the Persian version of DGI in MS patients. Materials and Methods: A total of 62 participants took part in the reliability process. The sample included 51 females and 11 males. Inter-rater reliability was assessed by the agreement of the results obtained by two occupational therapists. We considered a 3-day interval for the first and second data collection. Test-retest and inter-rater reliability were measured with the Intraclass Correlation Coefficient (ICC2, 1) and internal consistency was evaluated with the Cronbach alpha. Results: The Persian version of DGI showed excellent inter-rater reliability (ICC for total score was 0.98 and ICC for the items ranged from 0.83 to 0.96) and test-retest reliability (ICC for the overall score was 0.97 and ICC for the items ranged from 0.82 to 0.96). The Cronbach alpha of the Persian version of DGI was 0.87. Conclusion: The Persian version of DGI can be used as a reliable tool for dynamic balance measurement of MS patients in clinical settings and research studies.

Keywords

• Multiple sclerosis
• Gait
• Postural balance
• Psychometrics