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.
MethodThe 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.
ResultsThe 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.
ConclusionsThe Fototest is free from educational influence and shows appropriate testretest 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.
El Fototest es un test cognitivo breve aplicable a analfabetos, válido y útil para la detección de deterioro cognitivo y demencia. Nuestro objetivo es completar el proceso de desarrollo del instrumento llevando a cabo un estudio normativo y de fiabilidad.
MétodosEl estudio normativo se realizó en una muestra de conveniencia de 223 sujetos voluntarios sanos entre 20 y 85 años. La fiabilidad test-retest (Ftr) se evaluó mediante un diseño transversal de medidas repetidas en una muestra de 50 sujetos sin deterioro cognitivo; la fiabilidad interobservador (Fio) se determinó mediante la evaluación a ciegas de 10 aplicaciones del test por 30 observadores independientes; en ambos casos se utilizó el coeficiente de correlación intraclase. La evaluación de la consistencia interna (CI) se llevó a cabo mediante el coeficiente alfa de Cronbach.
ResultadosLos resultados del Fototest se distribuyen normalmente y no están influenciados por el sexo ni el nivel educativo, pero sí por la edad. La Ftr del Fototest es 0,89 (IC 95%: 0.81–0.93), la Fio es de 0,98 (IC 95%: 0.96–0.99) y 0,94 la CI.
ConclusionesEl Fototest está libre de influencias educativas y tiene una adecuada fiabilidad, tanto Ftr como Fio, y una alta consistencia interna, por tanto, es un instrumento adecuado para ser usado en el seguimiento de pacientes con deterioro cognitivo y demencia sobre todo en entornos en que cambien los evaluadores, en especial en poblaciones con bajo nivel educativo.
This paper is dedicated to the memory of María del Sagrario Barquero Jiménez who collaborated throughout and in the development of the Fototest. Part of this work was presented as an oral communication at the 49th Annual Meeting of the Spanish Neurological Society.