Normative and reliability study of Fototest

Abstract

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.