Cognitive Tests to Detect Dementia: A Systematic Review and Meta-analysis

Dementia is a global public health problem. The Mini-Mental State Examination (MMSE) is a proprietary instrument for detecting dementia, but many other tests are also available.

To evaluate the diagnostic performance of all cognitive tests for the detection of dementia.

Literature searches were performed on the list of dementia screening tests in MEDLINE, EMBASE, and PsychoINFO from the earliest available dates stated in the individual databases until September 1, 2014. Because Google Scholar searches literature with a combined ranking algorithm on citation counts and keywords in each article, our literature search was extended to Google Scholar with individual test names and dementia screening as a supplementary search.

Studies were eligible if participants were interviewed face to face with respective screening tests, and findings were compared with criterion standard diagnostic criteria for dementia. Bivariate random-effects models were used, and the area under the summary receiver-operating characteristic curve was used to present the overall performance.

Sensitivity, specificity, and positive and negative likelihood ratios were the main outcomes.

Eleven screening tests were identified among 149 studies with more than 49,000 participants. Most studies used the MMSE (n = 102) and included 10,263 patients with dementia. The combined sensitivity and specificity for detection of dementia were 0.81 (95% CI, 0.78-0.84) and 0.89 (95% CI, 0.87-0.91), respectively. Among the other 10 tests, the Mini-Cog test and Addenbrooke's Cognitive Examination-Revised (ACE-R) had the best diagnostic performances, which were comparable to that of the MMSE (Mini-Cog, 0.91 sensitivity and 0.86 specificity; ACE-R, 0.92 sensitivity and 0.89 specificity). Subgroup analysis revealed that only the Montreal Cognitive Assessment had comparable performance to the MMSE on detection of mild cognitive impairment with 0.89 sensitivity and 0.75 specificity.

Besides the MMSE, there are many other tests with comparable diagnostic performance for detecting dementia. The Mini-Cog test and the ACE-R are the best alternative screening tests for dementia, and the Montreal Cognitive Assessment is the best alternative for mild cognitive impairment.