Adaptación y validación psicométrica del Cuestionario de Consecuencias Funcionales del Dormir (Functional Outcomes Sleep Questionnaire [FOSQ]) en habitantes de la Ciudad de México

SUMMARY Excessive daytime sleepiness (EDS) is a highly disabling sleep disor- der related to alterations in behavioral performance, work injuries and vehicle accidents. A high prevalence of EDS (from 16% to 32%) in the general population has been reported. The Functional Outcomes Sleep Questionnaire (FOSQ) is an instrument that measures the im- pact of EDS in a patients functional state in different sleep disorders. This questionnaire has been validated in different countries (Norway, Turkey, Spain). Therefore, the objective of this study was to obtain the cultural validation, the internal consistency, construct validity and factor congruence of the adapted questionnaire for the inhabitants of Mexico City (FOSQ-Mexico). In the first part of the study we trans- lated the questionnaire using the standard methodological process. The FOSQ cultural adaptation was made by the Natural Modified Semantic Networks technique in a sample of 78 participants. In the second part, the adapted FOSQ was applied to 152 participants to test items discrimination, internal consistency, factor analysis by prin- cipal-components and factorial congruence with the original version. The principal-components analysis of the FOSQ yielded six meaning- ful factors that explained 67.2% of the total variance, an average  coefficient between 0.85 to 0.94 for the six factors. The factorial congruence coefficients ranged from 0.360 to 0.969 between the original and the FOSQ-Mexico version. This study demonstrated that the FOSQ version for inhabitants of Mexico City is reliable, valid and conceptually equivalent to the American version.