title: Improving the detection of chronic migraine: Development and validation of Identify Chronic Migraine (ID-CM).
abstract: BACKGROUND
  Migraine, particularly chronic migraine (CM), is underdiagnosed and undertreated worldwide. Our objective was to develop and validate a self-administered tool (ID-CM) to identify migraine and CM.
  
  
  METHODS
  ID-CM was developed in four stages. (1) Expert clinicians suggested candidate items from existing instruments and experience (Delphi Panel method). (2) Candidate items were reviewed by people with CM during cognitive debriefing interviews. (3) Items were administered to a Web panel of people with severe headache to assess psychometric properties and refine ID-CM. (4) Classification accuracy was assessed using an ICHD-3β gold-standard clinician diagnosis.
  
  
  RESULTS
  Stages 1 and 2 identified 20 items selected for psychometric validation in stage 3 (n = 1562). The 12 psychometrically robust items from stage 3 underwent validity testing in stage 4. A scoring algorithm applied to four symptom items (moderate/severe pain intensity, photophobia, phonophobia, nausea) accurately classified most migraine cases among 111 people (sensitivity = 83.5%, specificity = 88.5%). Augmenting this algorithm with eight items assessing headache frequency, disability, medication use, and planning disruption correctly classified most CM cases (sensitivity = 80.6%, specificity = 88.6%).
  
  
  CONCLUSIONS
  ID-CM is a simple yet accurate tool that correctly classifies most individuals with migraine and CM. Further testing in other settings will also be valuable.
authors.affiliation: Department of Neurology, Albert Einstein College of Medicine, USA Montefiore Headache Center, USA Richard.Lipton@einstein.yu.edu.
authors.forename: Richard B
authors.initials: RB
authors.lastname: Lipton
authors.affiliation: Department of Neurology, Albert Einstein College of Medicine, USA Endpoint Outcomes, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Serrano
authors.affiliation: Department of Neurology, Albert Einstein College of Medicine, USA Montefiore Headache Center, USA.
authors.forename: Dawn C
authors.initials: DC
authors.lastname: Buse
authors.affiliation: Department of Neurology, Albert Einstein College of Medicine, USA Montefiore Headache Center, USA.
authors.forename: Jelena M
authors.initials: JM
authors.lastname: Pavlovic
authors.affiliation: The Neurology Center, USA.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Blumenfeld
authors.affiliation: Department of Neurology, The Mayo Clinic, USA.
authors.forename: David W
authors.initials: DW
authors.lastname: Dodick
authors.affiliation: Department of Neurology, Stanford University Medical Center, USA.
authors.forename: Sheena K
authors.initials: SK
authors.lastname: Aurora
authors.affiliation: Department of Clinical Neurosciences, University of Calgary, Canada.
authors.forename: Werner J
authors.initials: WJ
authors.lastname: Becker
authors.affiliation: Department of Neurology, University of Duisbury-Essen, Germany.
authors.forename: Hans-Christoph
authors.initials: HC
authors.lastname: Diener
authors.affiliation: Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taiwan Faculty of Medicine, National Yang-Ming University School of Medicine, Taiwan.
authors.forename: Shuu-Jiun
authors.initials: SJ
authors.lastname: Wang
authors.affiliation: Department of Neurology, Universidade Federal do Rio de Janeiro, Brazil.
authors.forename: Maurice B
authors.initials: MB
authors.lastname: Vincent
authors.affiliation: Department of Neurology, Stanford University Medical Center, USA.
authors.forename: Nada A
authors.initials: NA
authors.lastname: Hindiyeh
authors.affiliation: Department of Neurology, The Mayo Clinic, USA.
authors.forename: Amaal J
authors.initials: AJ
authors.lastname: Starling
authors.affiliation: Allergan Inc, USA.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Gillard
authors.affiliation: Allergan Inc, USA.
authors.forename: Sepideh F
authors.initials: SF
authors.lastname: Varon
authors.affiliation: Vedanta Research, USA.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Reed
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000175:diagnosis*; D011594:Psychometrics / Q000379:methods*; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Chronic migraine; case-finding; diagnosis; migraine; screening; sensitivity; specificity; validation studies