Dysexecutive Questionnaire (DEX): Unrestricted structural analysis in large clinical and non-clinical samples

Abstract

Objective: The factorial structure of the Dysexecutive Questionnaire (DEX) is an unresolved issue in scientific literature. One-to-five-factor solutions have been found in several studies by applying different research methods. Only a few of these studies used appropriate analysis procedures to suit a Likert scale type of answer or investigated large enough samples to ensure the stability of factorial solutions. Method: The present study examines a sample of 2151 subjects, out of which 1482 formed part of the general population and 669 were taken out of a clinical population. An unrestricted factorial analysis was carried out on both samples. Results: the results unequivocally point to a single-factor solution in both samples. This means that only one latent variable is displayed in the DEX, which accounts for symptoms of oversight malfunction in activities of daily living. Conclusions: The diversity of results previously obtained in other studies may be due to using research methods that depict Likert–type scales on a continuum when they are actually ordinal categorical measures. In conclusion, the DEX should be considered a screening test that reports symptoms of prefrontal malfunction, although it is unable to specify what areas or functions have been affected, as previous studies have claimed.