Timed 360° turn test in people with Alzheimer′s disease: a reliability and validity study

BACKGROUND: Turning is an essential and challenging activity in daily life but is not specifically assessed for people with Alzheimer's disease (PwAD). The timed 360º turn test (360TT) is a specific tool assessing turning ability; however, its reliability and validity have not been established in Alzheimer's disease (AD). AIMS: To investigate: (1) the test-retest reliability of the 360TT in PwAD; (2) the standard error of measurement (SEM) and minimum detectable change (MDC) in the 360TT times; (3) the concurrent and known-groups validity of the 360TT times. METHODS: This cross-sectional study included 33 PwAD and 32 healthy people. The 360TT was administered along with the Berg Balance Scale, Timed Up and Go Test, and Mini-Mental State Examination. The test-retest reliability of the 360TT was examined by performing it twice at a 7-10 day interval for PwAD. RESULTS: values were 0.33 s and 0.91 s for the dominant side, while these values were 0.31 s and 0.85 s for the non-dominant side. The 360TT was correlated with the BBS, TUG, and MMSE in both sides (p < 0.05). PwAD took longer to complete the 360TT on both sides compared to healthy people (p < 0.001). CONCLUSIONS: The 360TT is a reliable and valid method in the evaluation of turning ability for PwAD. Clinicians and researchers can also use the 360TT to quantify changes in turning ability in AD.