title: Does screening history explain the ethnic differences in stage at diagnosis of cervical cancer in New Zealand?
abstract: BACKGROUND
  There are ethnic disparities in cervical cancer survival in New Zealand. The objectives of this study were to assess the associations of screening history, ethnicity, socio-economic status (SES) and rural residence with stage at diagnosis in women diagnosed with cervical cancer in New Zealand during 1994-2005.
  
  
  METHODS
  The 2323 cases were categorized as 'ever screened' if they had had at least one smear prior to 6 months before diagnosis, and as 'regular screening' if they had had no more than 36 months between any two smears in the period 6-114 months before diagnosis. Logistic regression was used to estimate the associations of screening history, ethnicity, SES and urban/rural residence with stage at diagnosis.
  
  
  RESULTS
  The percentages 'ever screened' were 43.3% overall, 24.8% in Pacific, 30.5% in Asian, 40.6% in Māori and 46.1% in 'Other' women. The corresponding estimates for 'regular screening' were 14.0, 5.7, 7.8, 12.5 and 15.3%. Women with 'regular screening' had a lower risk of late stage diagnosis [odds ratio (OR) 0.16, 95% confidence interval (CI) 0.10-0.26], and the effect was greater for squamous cell carcinoma (OR 0.12, 95% CI 0.07-0.23) than for adenocarcinoma (OR 0.32, 95% CI 0.13-0.82). The increased risk of late-stage diagnosis (OR 2.72, 95% CI 1.99-3.72) in Māori (compared with 'Other') women decreased only slightly when adjusted for screening history (OR 2.45, 95% CI 1.77-3.39).
  
  
  CONCLUSIONS
  Over half of cases had not been 'ever screened'. Regular screening substantially lowered the risk of being diagnosed at a late stage. However, screening history does not appear to explain the ethnic differences in stage at diagnosis.
authors.affiliation: Centre for Public Health Research, Massey University, Wellington, New Zealand. n.brewer@massey.ac.nz
authors.forename: Naomi
authors.initials: N
authors.lastname: Brewer
authors.forename: Neil
authors.initials: N
authors.lastname: Pearce
authors.forename: Mona
authors.initials: M
authors.lastname: Jeffreys
authors.forename: Barry
authors.initials: B
authors.lastname: Borman
authors.forename: Lis
authors.initials: L
authors.lastname: Ellison-Loschmann
mesh_terms: D005260:Female; D006801:Humans; D009367:Neoplasm Staging; D009520:New Zealand / Q000453:epidemiology; D012424:Rural Population / Q000706:statistics & numerical data; D012959:Socioeconomic Factors; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis* / Q000208:ethnology* / Q000401:mortality; D014626:Vaginal Smears / Q000706:statistics & numerical data