Cognitive failure can be understood as mental lapses that occur during the execution of a simple task. These failures can occur in different contexts, such as, for example, in occupational activities, in university students, in everyday life or in any other non-occupational context. The Occupational Cognitive Failures Questionnaire (OCFQ) is a measurement instrument that helps to understand cognitive failures in workers. However, the OCFQ was originally developed in English, requiring cross-cultural adaptation and testing of measurement properties to assess whether the adapted questionnaire can be used with the same confidence as the original questionnaire.

This study aims to test the measurement properties of the Occupational Cognitive Failures Questionnaire, translated, and adapted into Brazilian Portuguese. This is an observational, cross-sectional study.

The study population consisted of workers of both sexes, aged between 18 and 60 years.; and minimum working time on the task of three months. Workers with self-reported cognitive impairment (due to neurological diseases, mental disorders, dependence on alcohol and other drugs, depression) were excluded from the study. Participants were recruited by sharing the questionnaire through the UFSB e-mail, and digital media platforms such as Facebook and Instagram. For data collection, the following questionnaires were used: Sociodemographic Questionnaire; Prospective and Retrospective Memory Questionnaire – PRMQ; Occupational Cognitive Failures Questionnaire - OCFQ, were made available online through the Google Forms platform. The measurement properties were sociodemographic data; reproducibility; internal consistency; and ceiling and floor effect.

The sample consisted of 113 workers, of whom 13 were excluded for not meeting the requested criteria, mostly female workers with an average age of 29.4 years who perform office activities. Internal consistency was calculated using Cronbach's alpha index, with an adequate value of 0.84. The construct validity of the OCFQ and PRMQ instruments obtained Pearson's Correlation Coefficient value r = 0.5. The reproducibility evaluates the reliability tested with an intraclass correlation coefficient (ICC), consistency coefficient (ICCConcistency) with a value of 0.84, and agreement coefficient (ICCAgreement) of 0.1, showing a substantial reliability, and the agreement analyzed through the standard error of measurement (EPM) by the measurement (S.E. mean), with a value of 1.3%. No ceiling and floor effect was found.

We concluded that when testing the measurement properties of the Occupational Cognitive Failures Questionnaire instrument, in the translated and adapted version for Brazilian-Portuguese, it showed good results in terms of content validity, internal consistency, reproducibility, and construct validity.

Testing the measurement properties of the OCFQ questionnaire and its results makes it possible for professionals who work in occupational environments to use it, with the aim of detecting cognitive deficits in the workplace, to enable preventive actions for the worker, as well as greater safety in the work environment.