We examined the discriminant validity of the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE) in detecting multiple-domain mild cognitive impairment (md-MCI) in a Chinese sub-sample drawn from elderly population-based study.

This study included Chinese participants from the Epidemiology of Dementia in Singapore (EDIS) study aged ≥ 60 years who underwent cognitive screening with the Abbreviated Mental Test and Progressive Forgetfulness Questionnaire. Screen-positive participants subsequently underwent MoCA, MMSE, and a comprehensive formal neuropsychological battery. MCI was defined by Petersen's criteria and further classified into single-domain MCI (sd-MCI) and md-MCI. Area under the receiver operating characteristic curve (AUC) with 95% confidence intervals (CIs) was computed for the MoCA and the MMSE in detecting md-MCI.

A total of 300 participants were recruited: 128 (42.7%) were diagnosed with no cognitive impairment (NCI), 47 (15.7%) with sd-MCI, and 83 (28.0%) with md-MCI. Forty-one participants were excluded, 7 (2.3%) had dementia, and 34 (11.3%) had only objective cognitive impairment without subjective complaints. Although the MoCA had a significantly larger AUC than the MMSE (0.94 (95% CI = 0.91–0.97) vs. 0.91 (95% CI = 0.86–0.95), p= 0.04), at optimal cut-off points, the MoCA (19/20) was equivalent to the MMSE (25/26) in detecting md-MCI (sensitivity: 0.80 vs. 0.87, specificity: 0.92 vs. 0.80).

Both screening tests had good discriminant validity and can be used in detecting md-MCI in a sub-sample of Chinese drawn from a population-based study.