title: Patient-Centered Research to Support the Development of the Symptoms of Major Depressive Disorder Scale (SMDDS): Initial Qualitative Research.
abstract: BACKGROUND
  Content valid, patient-reported outcome (PRO) measures of major depressive disorder (MDD) symptoms are needed to assess MDD treatment benefit. While a range of questionnaires are currently available to evaluate aspects of depression from the patient's perspective, their comprehensiveness and qualitative development histories are unclear.
  
  
  OBJECTIVE
  The objective of this study was to describe the process and results of the preliminary qualitative development of a new symptom-based PRO measure intended to assess treatment benefit in MDD clinical trials.
  
  
  METHODS
  Qualitative interviews were conducted with adult MDD patients in the USA who recently experienced a major depressive episode. Experienced interviewers conducted concept elicitation (CE) and cognitive interviews using semi-structured interview guides. The CE interview guide was used to elicit spontaneous reports of symptom experiences along with probing to further explore and confirm concepts. The cognitive interview guide was developed to evaluate concept relevance, understandability, and structure of the draft items, and to facilitate further instrument refinement.
  
  
  RESULTS
  Forty patients participated in the CE interviews. A total of 3022 symptom codes, representing 84 different concepts were derived from the transcripts. Data from the CE interviews were considered alongside existing literature and clinical expert opinion during an item-generation process, leading to development of a preliminary version of the Symptoms of Major Depressive Disorder Scale (SMDDS). Fifteen patients participated in three waves of cognitive interviews, during which the SMDDS was further refined.
  
  
  CONCLUSIONS
  The SMDDS is a 35-item PRO measure intended for use as an endpoint in MDD clinical trials to support medical product labeling. The SMDDS uses a 7-day recall period and verbal rating scales. It was developed in accordance with the US Food and Drug Administration (FDA)'s PRO Guidance and best practices. Qualitative interviews have provided evidence for content validity. Future quantitative studies will confirm the SMDDS's measurement properties and support FDA qualification.
authors.affiliation: Health Research Associates, Inc., 6505 216th St. SW - Suite 105, Mountlake Terrace, WA, 98043, USA. mccarrier@hrainc.net.
authors.forename: Kelly P
authors.initials: KP
authors.lastname: McCarrier
authors.affiliation: Clinical Outcomes Assessment, Shire, Wayne, PA, USA.
authors.forename: Linda S
authors.initials: LS
authors.lastname: Deal
authors.affiliation: Outcomes and Evidence, Pfizer Ltd, Tadworth, Surrey, UK.
authors.forename: Lucy
authors.initials: L
authors.lastname: Abraham
authors.affiliation: Patient Reported Outcomes, GlaxoSmithKline, King of Prussia, PA, USA.
authors.forename: Steven I
authors.initials: SI
authors.lastname: Blum
authors.affiliation: PRO Center of Expertise, Eli Lilly and Company, Indianapolis, IN, USA.
authors.forename: Elizabeth Nicole
authors.initials: EN
authors.lastname: Bush
authors.affiliation: Health Research Associates, Inc., 6505 216th St. SW - Suite 105, Mountlake Terrace, WA, 98043, USA.
authors.forename: Mona L
authors.initials: ML
authors.lastname: Martin
authors.affiliation: Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, USA.|Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Thase
authors.affiliation: Patient-Reported Outcome Consortium, Critical Path Institute, Tucson, AZ, USA.
authors.forename: Stephen Joel
authors.initials: SJ
authors.lastname: Coons
mesh_terms: D000328:Adult; D002986:Clinical Trials as Topic / Q000379:methods / Q000592:standards*; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000523:psychology* / Q000628:therapy; D005260:Female; D006302:Health Services Research / Q000379:methods / Q000592:standards*; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods / Q000592:standards*; D010358:Patient Participation / Q000379:methods; D018802:Patient-Centered Care / Q000379:methods / Q000592:standards*; D011594:Psychometrics / Q000379:methods / Q000592:standards*; D055818:Public-Private Sector Partnerships; D036301:Qualitative Research; D012720:Severity of Illness Index; D014481:United States; D014486:United States Food and Drug Administration; D055815:Young Adult