title: Young Mania Rating Scale: how to interpret the numbers? Determination of a severity threshold and of the minimal clinically significant difference in the EMBLEM cohort.
abstract: The aim of this analysis was to identify Young Mania Rating Scale (YMRS) meaningful benchmarks for clinicians (severity threshold, minimal clinically significant difference [MCSD]) using the Clinical Global Impressions Bipolar (CGI-BP) mania scale, to provide a clinical perspective to randomized clinical trials (RCTs) results. We used the cohort of patients with acute manic/mixed state of bipolar disorders (N = 3459) included in the European Mania in Bipolar Longitudinal Evaluation of Medication (EMBLEM) study. A receiver-operating characteristic analysis was performed on randomly selected patients to determine the YMRS optimal severity threshold with CGI-BP mania score ≥ "Markedly ill" defining severity. The MCSD (clinically meaningful change in score relative to one point difference in CGI-BP mania for outcome measures) of YMRS, was assessed with a linear regression on baseline data. At baseline, YMRS mean score was 26.4 (±9.9), CGI-BP mania mean score was 4.8 (±1.0) and 61.7% of patients had a score ≥ 5. The optimal YMRS severity threshold of 25 (positive predictive value [PPV] = 83.0%; negative predictive value [NPV] = 66.0%) was determined. In this cohort, a YMRS score of 20 (typical cutoff for RCTs inclusion criteria) corresponds to a PPV of 74.6% and to a NPV of 77.6%, meaning that the majority of patients included would be classified as severely ill. The YMRS minimal clinically significant difference was 6.6 points.
authors.affiliation: AP-HP, Paul-Brousse Hospital, Department of Psychiatry and Addictology, Villejuif, France.
authors.forename: Michael
authors.initials: M
authors.lastname: Lukasiewicz
authors.forename: Stephanie
authors.initials: S
authors.lastname: Gerard
authors.forename: Adeline
authors.initials: A
authors.lastname: Besnard
authors.forename: Bruno
authors.initials: B
authors.lastname: Falissard
authors.forename: Elena
authors.initials: E
authors.lastname: Perrin
authors.forename: Helene
authors.initials: H
authors.lastname: Sapin
authors.forename: Mauricio
authors.initials: M
authors.lastname: Tohen
authors.forename: Catherine
authors.initials: C
authors.lastname: Reed
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Azorin
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000175:diagnosis*; D015331:Cohort Studies; D005060:Europe; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D019370:Observation; D011569:Psychiatric Status Rating Scales; D012372:ROC Curve; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013997:Time Factors