Abstract
Background: Mental workload has emerged as one of the most important occupational risk factors present in most psychological and physical diseases caused by work. In view of the lack of specific tools to assess mental workload, the objective of this research was to assess the construct validity and reliability of a new questionnaire for mental workload assessment (CarMen-Q). Method: The sample was composed of 884 workers from several professional sectors, between 18 and 65 years old, 53.4% men and 46.6% women. To evaluate the validity based on relationships with other measures, the NASA-TLX scale was also administered. Results: Confirmatory factor analysis showed an internal structure made up of four dimensions: cognitive, temporal and emotional demands and performance requirement. The results show satisfactory evidence of validity based on relationships with NASA-TLX and good reliability. Conclusions: The questionnaire has good psychometric properties and can be an easy, brief, useful tool for mental workload diagnosis and prevention.