Feasibility, Reliability, and Validity of the Vietnamese Version of the Clinical Dementia Rating.

ABSTRACT

INTRODUCTION: In Vietnam, Alzheimer's disease (AD) and other dementias have become an increasingly important public health problem among the elderly. Achieving a diagnosis tool with high reliability and validity is essential. The Clinical Dementia Rating (CDR) is a global clinical scale with established diagnostic and severity-ranking utility that has been widely employed in epidemiological studies in an international context. OBJECTIVE: The aims of this study were to establish the Vietnamese version of the CDR (V-CDR) and evaluate the feasibility, reliability, and validity of this version for diagnosing and classifying cognitive functions in the elderly. METHOD: One hundred and fifty-three elderly outpatients at a clinic of Cho Ray Hospital, Vietnam, were screened with the Mini Mental State Examination (MMSE) for potential cognitive impairment. All those who scored ≤26 points were included in the study and were subsequently remitted to the V-CDR and clinical assessment for diagnosis. Reliability was assessed through internal consistency (Cronbach α), intra- and interrater reliability (weighted κ). Concurrent and discriminative validity of the V-CDR were assessed. RESULTS: The V-CDR had an excellent internal consistency for each of the 2 raters (Cronbach α 0.90 and 0.96) and excellent agreement in both intra- and interrater reliability (weighted κ 0.84 [95% CI 0.74-0.94] and 0.82 [95% CI 0.72-0.93], respectively). The sensitivity and specificity for detecting dementia were 93.6 and 100%, respectively. The positive and negative predictive value were 100 and 96.4%, respectively. The agreement of V-CDR and clinical assessment was excellent (weighted κ 0.94 [95% CI 0.88-0.99]). V-CDR was substantially better than MMSE at distinguishing between mild cognitive impairment and normal cognitive function (AUC = 0.957, 95% CI 0.893-1.000 vs. AUC 0.594, 95% CI 0.441-0.746). CONCLUSIONS: The V-CDR is a feasible, reliable, and valid instrument which should be used in clinical practice for diagnosing and classifying the different dementia stages in the elderly.