Diagnostic accuracy of neuropsychological tests for classification of dementia

Although numerous studies have shown that each neuropsychological test is effective for diagnosing mild cognitive impairment (MCI) or Alzheimer’s disease (AD), studies comparing diagnostic accuracies of various neuropsychological tests are relatively rare and practical cutoff values are not available. The present study aimed to investigate the validity of neuropsychological tests and develop cutoff values for each in differentiating healthy control (HC), MCI and AD groups. A total of 84 HC, 187 with MCI and 195 with AD were evaluated by the selected seven neuropsychological tests using receiver operating characteristic (ROC) curve analysis. Logical Memory (LM) delayed recall (cutoff, 7) and Rey Auditory Verbal Learning Test (RAVLT) delayed recall (cutoff, 6) were effective for differentiating HC from MCI. To distinguish MCI and AD, Rey Osterrieth Complex Figure Test (ROCFT) 3 mindelayed recall (cutoff, 6) and LM immediate recall (cutoff, 4) were excellent. Delayed recall of verbal materials, as indexed by LM and RAVLT was sensitive for discriminating MCI from HC. Handling visual memory traces, as indexed by ROCFT and immediate verbal information by LM were sensitive for differentiating MCI and AD.