title: Which strategy should be applied? Design of a Norwegian epidemiological survey on chronic headache.
abstract: BACKGROUND
  Large-scale population-based epidemiological surveys on chronic headache based on clinical interview by a physician are lacking.
  
  
  OBJECTIVE
  To describe a method that aims to provide valid information on chronic headache.
  
  
  METHODS
  A self-administered questionnaire including two questions about headache frequency within the last month and within the last year was used to screen for possible chronic headache. Respondents with self-reported headache more than half of the days were interviewed by neurological residents with experience in headache diagnostics.
  
  
  CONCLUSIONS
  Previous studies have shown that a single question from a self-administered questionnaire can be used to screen for chronic headache. However, a precise headache diagnosis requires an interview by a physician experienced in headache diagnostics, as diagnoses extracted from questionnaires or provided by lay interviewers are not sufficiently precise.
  
  
  CONCLUSIONS
  A combination of a screening questionnaire and a clinical interview by a physician is likely to be a cost-effective method to conduct an epidemiological survey on chronic headache.
authors.affiliation: Head and neck research group, Akershus University Hospital, Nordbyhagen, Oslo, Norway. m.b.russell@medisin.uio.no
authors.forename: M B
authors.initials: MB
authors.lastname: Russell
authors.forename: K
authors.initials: K
authors.lastname: Aaseth
authors.forename: R B
authors.initials: RB
authors.lastname: Grande
authors.forename: P
authors.initials: P
authors.lastname: Gulbrandsen
authors.forename: C
authors.initials: C
authors.lastname: Lundqvist
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D003951:Diagnostic Errors / Q000517:prevention & control; D015340:Epidemiologic Research Design; D016021:Epidemiologic Studies; D005260:Female; D020773:Headache Disorders / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D007407:Interviews as Topic / Q000592:standards; D008297:Male; D008403:Mass Screening / Q000379:methods; D009664:Norway / Q000453:epidemiology; D010819:Physician's Role; D011795:Surveys and Questionnaires / Q000592:standards*