Swedish version of mood spectrum self-report questionnaire: Psychometric properties of lifetime and last-week version

Background: Mood Spectrum Self Report (MOODS-SR) is an instrument that assesses mood spectrum symptomatology including subthreshold manifestations and temperamental features. There are different versions of the MOODS-SR for different time frames of symptom assessment: lifetime (MOODS-LT), last-month and last-week (MOODS-LW) versions. Objective: To evaluate the psychometric properties of the MOODS-LT the MOODS-LW. Methods: The reliability of the MOODS-LT and MOODS-LW was evaluated in terms of internal consistency and partial correlations among domains and subdomains. The known-group validity was tested by comparing out-patients with bipolar disorder (n=27), unipolar depression (n=8) healthy controls (n=68). The convergent and divergent validity of MOODS-LW were evaluated using the Montgomery Asberg Depression Rating Scale (MADRS), the Young-Ziegler Mania Rating Scale (YMRS) in outpatients as well the General Health Questionnaire (GHQ-12) in healthy controls. Results: Both MOODS-LT and MOOODS-LW showed high internal consistency with the Kuder-Richardson coefficient ranging from 0.823 to 0.985 as well as consistent correlations for all domains and subdomains. The last-week version correlated significantly with MADRS (r= 0.79) and YMRS (r=0.46) in outpatients and with GHQ-12 (r= 0.50 for depression domain, r= 0.29 for rhythmicity) in healthy controls. Conclusion: The Swedish version of the MOODS-LT showed similar psychometric properties to other translated versions. Regarding MOODSLW, this first published psychometric evaluation of the scale showed promising psychometric properties including good correlation to established symptom assessment scales. In healthy controls, the depression and rhythmicity domain scores of the last-week version correlated significantly with the occurrence of mild psychological distress.