title: The effect of gender in clinically isolated syndrome (CIS): a meta-analysis.
abstract: OBJECTIVE
  A clinically isolated syndrome compatible with demyelination (CIS) is the initial presentation for the majority of people that go on to develop multiple sclerosis (MS). There has previously been little work examining the effect of gender on the development and progression of CIS.
  
  
  METHODS
  Data from observational studies of CIS were used. In total, 33 suitable studies with 4732 subjects were identified.
  
  
  RESULTS
  The overall relative risk (RR) of CIS in females compared with males was 2.12 (95% CI 1.94-2.32). The RR of females developing MS following CIS was 1.20 (95% CI 0.98-1.46) compared with males.
  
  
  CONCLUSIONS
  These data imply that the gender bias seen in MS is caused by factors acting early in the disease process.
authors: Blizard Institute, Queen Mary University of London, Barts and the London School of Medicine and Dentistry, London, UK. ruth.dobson@qmul.ac.uk
authors: Ruth
authors: R
authors: Dobson
authors: Sreeram
authors: S
authors: Ramagopalan
authors: Gavin
authors: G
authors: Giovannoni
mesh_terms: D016009:Chi-Square Distribution; D003711:Demyelinating Diseases / Q000453:epidemiology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000453:epidemiology*; D016017:Odds Ratio; D011379:Prognosis; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors