Comparing Diagnostic Accuracy of Cognitive Screening Instruments: A Weighted Comparison Approach

Abstract

Background/Aims: There are many cognitive screening instruments available to clinicians when assessing patients' cognitive function, but the best way to compare the diagnostic utility of these tests is uncertain. One method is to undertake a weighted comparison which takes into account the difference in sensitivity and specificity of two tests, the relative clinical misclassification costs of true- and false-positive diagnosis, and also disease prevalence. Methods: Data were examined from four pragmatic diagnostic accuracy studies from one clinic which compared the Mini-Mental State Examination (MMSE) with the Addenbrooke's Cognitive Examination-Revised (ACE-R), the Montreal Cognitive Assessment (MoCA), the Test Your Memory (TYM) test, and the Mini-Mental Parkinson (MMP), respectively. Results: Weighted comparison calculations suggested a net benefit for ACE-R, MoCA, and MMP compared to MMSE, but a net loss for TYM test compared to MMSE. Conclusion: Routine incorporation of weighted comparison or other similar net benefit measures into diagnostic accuracy studies merits consideration to better inform clinicians of the relative value of cognitive screening instruments.