Development of a clinical measure of dual-task performance in walking: reliability and preliminary validity of the Walking and Remembering Test.

OBJECTIVES: (1) To examine the reliability of a new clinical measure of simultaneous walking with performance of a working memory task, the Walking and Remembering Test (WART). (2) To compare older adult to younger adult WART performance to illustrate preliminary validity.

SUBJECTS: Convenience sample of 25 young adults (ages 22-35) and 25 older adults (ages 65-86) performed the WART twice.

METHODS: Subjects walked 6.1 meters at their fastest safe speed along a path requiring a narrowed base of support in both single and dual-task (with simultaneous digit span task) conditions. Reductions in walking and cognitive performance were examined in the dual-task condition for older adults as compared to younger adults.

MAIN OUTCOME MEASURES: Walking time, step accuracy, digit span memory accuracy, and dual-task costs for walking and cognitive tasks.

RESULTS: Inter-rater reliability ICC (2,1) values were > or = .97 for walking time and digit span accuracy. Rater agreement of steps off the path was excellent (93%) for young adults and good (76%) for older adults. Test-retest reliability ICC (2,1) values for walking time were > or = .79. Older adults were slower and remembered shorter digit spans, and demonstrated greater dual-task costs for digit span accuracy and steps off the path than younger adults, but relative dual-task costs for walking time were not significantly different between groups.

CONCLUSIONS: The WART is a reliable clinical measure of dual-task memory and walking that can be administered safely with community-dwelling older adults. Expected greater dual-task costs for older adults were observed, but not as strongly as anticipated in this group of very active subjects. The WART provides information that may be useful in targeting patients for intervention to reduce risk of falls in dual-task conditions, but needs validation with older adults across a greater range of walking ability.