Performance of the Rowland Universal Dementia Assessment Scale in Screening Mild Cognitive Impairment at an Outpatient Setting.

Introduction: Mild cognitive impairment (MCI) is defined as the symptomatic pre-dementia phase on the continuum of cognitive decline. Early recognition and application of potential interventions could prevent or delay the progression to dementia. The Rowland Universal Dementia Assessment Scale (RUDAS) shows good performance in the screening of dementia but has limited data regarding its diagnostic properties in the screening of MCI. The objectives of this study were to assess the psychometric properties of the Thai version of the RUDAS (RUDAS-Thai) in the screening of MCI, identify associated factors for the RUDAS performance, and determine the optimal cutoff point in detecting MCI.

Methods: This was a cross-sectional study conducted from January 2020 to March 2021. Older patients at the outpatient clinic of an internal medicine department at a tertiary care hospital in Thailand were examined. Baseline data were collected, and the RUDAS-Thai was administered to each patient. Afterward, a geriatrician assessed each patient for MCI.

Results: A total of 150 patients were included, of whom 42 cases (28%) had MCI. The overall performance of the test using an area under the receiver operating characteristic curve (AUC) was 0.82 (95% confidence interval 0.75-0.89). At the optimal cutoff point of 25/30, the AUC was 0.76 with sensitivity and specificity of 76.2 and 75%, respectively. The educational level affected the test performance according to regression analysis. For patients with years of education ≤6 and >6, the optimal cutoff points were 25/30 and 26/30, respectively.

Conclusion: The RUDAS-Thai performed well in differentiating patients with MCI from normal cognition; however, it was affected by educational level. A score of 25/30 or lower for persons with ≤6 years of education or 26/30 or lower for persons with higher than 6 years of education is the optimal cutoff point for indication of developing MCI.