Construction and validation of the 4-item dynamic gait index

Abstract

Background and purpose: People with balance disorders often have difficulty walking. The purpose of this study was to develop and test the psychometric properties of a short form of the Dynamic Gait Index (DGI) for the clinical measurement of walking function in people with balance and vestibular disorders.

Subjects: A total of 123 subjects with such disorders (test subjects) and 103 control subjects were included in this study.

Methods: Rasch and factor analyses were used to create a short form of the DGI. Internal consistency and discriminative validity for test subjects versus control subjects and for falling versus nonfalling test subjects were evaluated.

Results: Four items were selected for the shorter version of the test: gait on level surfaces, changes in gait speed, and horizontal and vertical head turns.

Discussion and conclusion: The clinical psychometric properties of the 4-item DGI were equivalent or superior to those of the 8-item test. The 4-item DGI can be used by clinicians to measure gait in people with balance and vestibular disorders without compromising important clinical measurement characteristics.