Related Experiment Video
Updated: Jun 11, 2026
A Machine Learning Approach to Design an Efficient Selective Screening of Mild Cognitive Impairment
Published on: January 11, 2020
Diagnostic performance of an Executive Clock Drawing Task (CLOX) as a screening test for mild cognitive impairment in
Paola Forti1, Valentina Olivelli, Elisa Rietti
1Department of Internal Medicine, Ageing, and Nephrology, University Hospital St. Orsola-Malpighi, University of Bologna, Bologna, Italy. paola.forti@unibo.it
Background:
CLOX, a clock drawing test protocol uniquely sensitive to impairment of executive functions, has been proposed as a screening tool for mild cognitive impairment (MCI), but data about its diagnostic efficiency are lacking.
Methods:
There are data for 196 subjects, age >or=60 years, referred to a memory clinic for cognitive complaints. After extensive neuropsychological testing, 64 were diagnosed as cognitively normal and 132 with MCI.
Results:
At standard cutoffs, both CLOX subtests had a fair specificity (CLOX1 72%, CLOX2 92%) but unacceptably low values of sensitivity (CLOX1 54%, CLOX2 28%) and likelihood ratio (CLOX1 1.91, CLOX2 3.59) for MCI. The use of different cutoffs or the combination of CLOX with the Mini-Mental State Examination (MMSE) did not statistically increase diagnostic efficiency.
Conclusion:
CLOX, either alone or in combination with MMSE, is not a useful screening test for MCI in a clinical setting.
