Normative and reliability study of Fototest.

INTRODUCTION

The Fototest is a brief cognitive test suitable for illiterate persons, and valid and accurate for detecting cognitive impairment or dementia. Our aim was to conclude the development of this instrument carrying out a normative and reliability study.

METHOD

The normative study was performed on a convenience sample of 223 healthy volunteers aged between 20 and 85 years. The test-retest reliability was assessed through a repeated-measures cross-sectional design on a sample of 50 subjects with no cognitive impairment; the inter-rater reliability was determined by the blind assessment of 10 test applications performed by 30 independent observers; in both instances, reliability was expressed as intra-class correlation coefficient. Internal consistency was analysed by Cronbach's alpha coefficient.

RESULTS

The results on the Fototest are normally distributed and are not influenced by gender or educational level but they do vary with age. The test-retest reliability of the Fototest was 0.89 (95% CI: 0.81-0.93); the inter-rater reliability, 0.98 (95% CI: 0.96-0.99); and the internal consistency, 0.94.

CONCLUSIONS

The Fototest is free from educational influence and shows appropriate test-retest and inter-rater reliabilities, as well as a high internal consistency. Therefore, it is a suitable psychometric instrument to be used in the follow-up of patients with cognitive impairment or dementia, especially in contexts where evaluators are not the same on different occasions, or with patients of low educational level.