[Clock drawing test: qualitative and quantitative evaluation methods]

Abstract

Introduction: The interest about the Clock Drawing Test (CDT) is justified because the importance of praxic disorders and especially the constructive apraxias in demented patients. Generally, this kind of deficits or intellectual losses has been less studied than aphasisas and agnosias. Nevertheless, praxias are usually affected in demential processes, even in initial stages.

Objective: We try to determine if the CDT can be useful as an assessment tool for dementia. We have used two assessment systems of the clock drawing in order to select an useful and reliable method of correction.

Patients and methods: The sample is made up of 35 subjects older than 60 years, they were administered the Mini Cognitive Examination (MCE) and the CDT. Patients with previous diagnosis of dementia, others with physical pathology without neurological affectation and, finally, subjects without any kind of pathology were included in order to get a wide rank of punctuations. We carried out a reliability analysis between two raters and the discriminant validity of the CDT compared to the Spanish adaptation of the Mini Mental Examination.

Results: We achieve a high reliability inter examiner rates. Quantitative criteria of both scales are more objective than qualitative ones, therefore, these last should be more operativized.

Conclusions: The results obtained in this work suggest that the clock drawing allow a rapid evaluation of cognitive function as the presence of cognitive impairment.