Reliability of the Physical Performance Test in People with Dementia

ABSTRACT

Purpose. Approximately 30% of older adults have dementia. Disease progression has been found to be the largest predictor of function, and dementia has been found to influence fall risk. In order to identify individuals with dementia who may benefit from interventions to increase function and decrease fall risk, assessment tools for these domains that are validated in this population are necessary. The 7-item Physical Performance Test (PPT) is a valid measure of balance and function in older adults; however, its reliability has not been established in those with dementia. The purpose of this study was to establish intra-tester, inter-tester, and test–retest reliability of the 7-item PPT in people with dementia. Methods. Thirty-three subjects with a diagnosis of dementia and a Mini-Mental State Examination (MMSE) score between 10 and 24 were tested with the PPT on two separate days with performance on the second day videotaped. One tester scored the videotaped performance on two separate occasions and intra-tester reliability was determined using an intraclass correlating coefficient (ICC) (3,1). Two testers independently scored the videotaped performances and inter-tester reliability was determined using an ICC (2,1). Scores from the first and second testing days were compared and test–retest reliability was determined using an ICC (3,1). Results. All subjects completed both testing sessions and reliability was established for intra-tester, inter-tester, and test–retest with ICCs of 0.99, 0.96, and 0.90, respectively. Conclusion. The 7-item PPT is reliable for use in people with mild to moderate dementia as defined by MMSE scores between 10 and 24.

KEYWORDS. :

• Dementia
• reliability
• physical performance test
• function
• balance