Translation, adaptation and construct validation of the Clock Test among elderly in Brazil

In Brazil, not many studies have investigated the validation of cognitive tests in the ageing population and none of them has analyzed the psychometric properties of Tuokko's Clock Test. The objective of the study was to translate and adapt the test to the Brazilian context, and to assess its construct validation.

This is a cross-sectional population-based study, involving 353 elderly patients from Juiz de Fora (Southeastern Brazil), from 2004-2005. To assess convergent and divergent validities Pearson's correlation statistics was used. The Clock Test substests were correlated with theses reference instruments: mini-mental state examination, digits, block design to evaluate the convergent validity. the divergent validity was assessed by comparing the substests to the Center for Epidemiologic Studies Depression Scale.

In the sample, 74.1% were women, aged between 63 and 107 years (73.8+/-8.5), average schooling was 7.4 years (SD=4.7). In regard to convergent validity, significant correlations were found between all CT subtests and MMSE, Digits, and Block Design (p<0.01). As for the divergent validity, the only subtest that had significant association with the reference scale was the "clock setting" (p<0.05).

The translated and validated Clock Test into a community sample of aged showed to be a brief screening instrument, with good construct validity when compared to other studies. Future research must investigate other psychometric properties, such as content and criterion validities.