Clinical measures that Quantify falling risk factors are needed for the accurate evaluation of patients and to plan an intervention strategy. The purpose of this study was to examine the test-retest and interrater reliability of the dynamic gait index (DGI) for persons with Parkinson's disease (PD). A total of 22 idiopathic PD patients were recruited from rehabilitation hospital, Korea in this study. The DGI was assessed in two sessions that were, three days apart. We also measured Berg balance test (BBT) and geriatric depression scale (GDS) for concurrent validity with DGI. Intrarater and interrater reliability (.96 and .98 respectively) for DGI were high. indicating good agreement. The DGI was showed a good positive correlation with the BBS (r=.852). but not GDS (r=-.462). Intrarater and interrater reliability of DGI were high in people with PD. The DGI could be a reliable measure to evaluate functional postural control during gait activities in the PD population, and the ability of DGI to detect real change is acceptable in research and clinical settings.

The Dynamic Gait Index (DGI) was developed and widely used as a clinical tool to assess balance performance during gait. The purpose of this study was to validate the Korean translated DGI using Rasch analysis. A total of 105 community-dwelling elderly was participated in this study (age range = 65~95 years; mean = 78.0 years). The translated DGI showed sound item psychometric properties, and the 8 items were arranged in order of difficulty for the total participants. The most difficult item was 'Steps' and the easiest item was 'Level surface'. Also, each of the original 4 rating scale categories satisfied the Linacre's essential criteria suggestions for optimal rating scale category effectiveness. Although, thirty eight person (36.2%) showed the maximal high score, but the most of them was no history of fall in the preceding year. For subjects who has falling history, all of the person's ability was arranged within the item's difficulty. The 8-item Korean translated DGI can be used to measure gain in elderly person with balance disorders without compromising important clinical measurement characteristics in Korea.