Abstract
BACKGROUND: Measurement-based care is an effective clinical strategy underutilized for bipolar disorder partly due to lacking a widely adopted patient-reported manic symptom measure. OBJECTIVE: To report development and psychometric properties of a brief patient-reported manic symptom measure. DESIGN: Secondary analysis of data collected in a randomized effectiveness trial comparing two treatments for 1004 primary care patients screening positive for bipolar disorder and/or PTSD. PARTICIPANTS: Two analytic samples included 114 participants with varied diagnoses and test-retest data, and 179 participants with psychiatrist-diagnosed bipolar disorder who had two or more assessments with the nine-item Patient Mania Questionnaire-9 [PMQ-9]). MAIN MEASURES: Internal and test-retest reliability, concurrent validity, and sensitivity to change were assessed. Minimally important difference (MID) was estimated by standard error of measurement (SEM) and by standard deviation (SD) effect sizes. KEY RESULTS: The PMQ-9 had high internal reliability (Cronbach's alpha = 0.88) and test-retest reliability (0.85). Concurrent validity correlation with manic symptom measures was high for the Internal State Scale-Activation Subscale (0.70; p<0.0001), and lower for the Altman Mania Rating Scale (0.26; p=0.007). Longitudinally, PMQ-9 was completed at 1511 clinical encounters in 179 patients with bipolar disorder. Mean PMQ-9 score at first and last encounters was 14.5 (SD 6.5) and 10.1 (SD 7.0), a 27% decrease in mean score during treatment, suggesting sensitivity to change. A point estimate of the MID was approximately 3 points (range of 2-4). CONCLUSIONS: The PMQ-9 demonstrated excellent test-retest reliability, concurrent validity, internal consistency, and sensitivity to change and was widely used and acceptable to patients and clinicians in a pragmatic clinical trial. Combined with the Patient Health Questionnaire-9 (PHQ-9) measure of depressive symptoms this brief measure could inform measurement-based care for individuals with bipolar disorder in primary care and mental health care settings given its ease of administration and familiar self-report response format.