Reliability of 4-m and 6-m walking speed tests in elderly people with cognitive impairment.

The purpose of this study was to evaluate the interrater and test-retest reliability of 4-m and 6-m walking speed tests in elderly people with cognitive impairment. 50 subjects aged 65 and over with cognitive impairment were selected from an adult day-care centre and a nursing home. To examine interrater reliability, 21 people were evaluated independently by two researchers who administered the 4-m and 6-m walking tests in each evaluation. For test-retest reliability, two observers administered the tests to the same 29 subjects, with a time interval of one week. Intraclass correlation coefficients (ICCs) were calculated to examine interrater and test-retest reliability. The ICCs for interrater reliability reached values of 0.96 and 0.88 for the 4-m and 6-m walking tests, respectively. In the test-retest study, the time interval was 7.4±1.17 days. The ICCs were 0.91 for the 4-m test and 0.86 for the 6-m test. The results support the use of walking tests in elderly people with cognitive impairment.