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

Test-retest reliability of the 360TT was excellent for the dominant and non-dominant sides (ICC = 0.957 and ICC = 0.916, respectively). The SEM95 and MDC95 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.