A comparison of the diagnostic accuracy of the Mini-Cog and AD8 in identifying cognitive impairment in a geriatric health screening population in China

The present study aimed to evaluate and compare the discriminative abilities of the Mini-Cog and AD8 tests in detecting cognitive impairment in a Chinese health screening population. 160 geriatric participants were enrolled at an academic medical center . The Mini-Cog, AD8, and Mini-Mental State Examination (MMSE) were used to assess the possibility of cognitive impairment. Logistic regression and receiver operator characteristic curve analyses were performed to evaluate the discriminative abilities of the tests. The prevalence of cognitive impairment was 41.25%. Logistic regression modeling showed that the Mini-Cog (odds ratio (OR) = 0.34, 95% confidence interval (CI): 0.25-0.46) and MMSE (OR = 0.58, 95%CI: 0.49-0.69) predicted cognitive impairment with 79.4% and 80.6% correct classification, respectively. While the AD8 (OR = 1.56, 95% CI: 1.32-1.85) predicted cognitive impairment with 72.5% correct classification. The areas under the receiver operating characteristic curves of the Mini-Cog, AD8 and MMSE for detecting cognitive impairment were 0.79 (95% CI: 0.72-0.85), 0.66 (95% CI: 0.58-0.73) and 0.80 (95% CI: 0.73-0.86). Both sensitivity and specificity of the Mini-Cog were superior to those of the AD8 (sensitivity 78.79% vs. 56.06%; specificity 79.79% vs. 75.53%). Cognitive screening is crucial to maintain the quality of life of older adults. Compared with the AD8, the Mini-Cog test is a more effective tool for screening cognitive impairment in older adults.