The Correlation between the Montreal Cognitive Assessment (MoCA) and the Rowland Universal Dementia Assessment Scale (RUDAS) for the Detection of Mild Neurocognitive Disorder among Older Patients in an Outpatient Setting

Abstract

Objective: To demonstrate the correlation and develop conversion scores between the Montreal Cognitive Assessment (MoCA) and Rowland Universal Dementia Assessment Scale (RUDAS) in patients with mild neurocognitive disorder (NCD). Materials and Methods: A cross-sectional study of outpatients aged >60 years of the general geriatric clinic of Ramathibodi Hospital, Thailand between February 2020 and March 2021 was conducted. Baseline information was collected, and the MoCA and RUDAS were administered to each patient by a clinical psychologist. Subsequently, geriatricians assessed each patient for mild NCD according to the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders-5. Results: A total of 156 patients were recruited and mild NCD was identified in 117 patients (75%). The Pearson correlation coefficient between the tests was 0.4 (p<0.00). The RUDAS-MoCA conversion score was developed where age and educational level were the independent factors associated with those tests. A conversion formulation was MoCA=5.91-1.61(age)-1.51(years of education)+0.61(RUDAS score); where age <70 years scores 0 and age 70 years or over scores 1, and 6 years of education or lower scores 0 and more than 6 years of education scores 1. Conclusion: The RUDAS and MOCA had a positive correlation, and the conversion table was developed to simplify the smooth transition of the scores in patients with mild NCD.