Swedish translation and reliability of the Morningness-Eveningness Questionnaire

Introduction Chronotherapy is used as an adjuvant treatment for depression in addition to pharmacological and psychological treatments. The Morningness-Eveningness Questionnaire (MEQ) is used to classify a person's sleep and activity pattern. The aim was to translate the MEQ to Swedish and evaluate the reliability. In addition, MEQ scores between a healthy study group and patient group were compared. Lastly, patient MEQ and MADRS scores were checked for correlation. Method The MEQ was translated and back-translated. The MEQ was administered to a healthy study group ( n =285) where a subset of these filled out the MEQ a second time. Cronbach's α was used for internal consistency and Wilcoxon signed rank test and Spearman correlation was used for test-retest reliability. Spearman correlation was used for the patient group ( n =26) MEQ and MADRS scores. Results Internal consistency of the MEQ was 0.903. Wilcoxon signed rank test showed small statistically significant differences between test and retest and Spearman correlation for the total score was 0.97. The MEQ scores of the healthy study group and patient group showed similar mean scores and distribution. There was no statistically significant difference between the means ( P =0.34). There was no correlation between patient MEQ and MADRS score ( r =0.01). Conclusion MEQ is a reliable scale in a Swedish healthy population as well as inpatients with depression.