title: Age-period-cohort effect on mortality from cervical cancer.
abstract: OBJECTIVE
  To estimate the effect of age, period and birth cohort on mortality from cancer of the cervix.
  
  
  METHODS
  Mortality data for cervical cancer in women aged over 30, between 1980 and 2009, for the municipalities of Rio de Janeiro and Sao Paulo, Southeastern Brazil,were extracted from the Mortality Information System. The estimated annual percentage change was calculated for the periods 1980-1994 and 1995-2009. Age, period and cohort effects were assessed employing the Poisson regression model, using estimated functions, deviations, curvatures and drift through the library Epi statistical program R version 2.7.2.
  
  
  RESULTS
  The average mortality rate per 100,000 women for the period in Rio de Janeiro was 15.90 and 15.87 in Sao Paulo. There was a significant reduction in mortality from cervical cancer in the two periods (1980-1994 and 1995-2009) in both Rio de Janeiro, -1.20% (95%CI -2.20;-0.09) -1.46% (95%CI -2.30;0.61) and in Sao Paulo, -2.58% (95%CI -3.41;1.76) and -3.30% (95%CI -4.30;2.29). The analysis of effects of curvature indicated reduction in deaths in successive cohorts (RR < 1 in women born after the 1960s). There was marked reduction in relative risk (RR) from the 2000s onwards.
  
  
  CONCLUSIONS
  The study showed that, in the time period analyzed, the period had an effect on the reduction in mortality rates for cervical cancer, bearing in mind that there was a protective effect (RR < 1) from the year 2000 onwards and in women born after the 1960s.
authors.affiliation: Fundação Oswaldo Cruz, Escola Nacional de Saúde Pública Sergio Arouca, Programa de Epidemiologia em Saúde Pública, Rio de JaneiroRJBrazil.
authors.forename: Karina Cardoso
authors.initials: KC
authors.lastname: Meira
authors.forename: Gulnar Azevedo e
authors.initials: GA
authors.lastname: Silva
authors.forename: Cosme Marcelo Furtado Passos da
authors.initials: CM
authors.lastname: Silva
authors.forename: Joaquim Gonçalves
authors.initials: JG
authors.lastname: Valente
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D001938:Brazil / Q000453:epidemiology; D015988:Cohort Effect; D005260:Female; D006801:Humans; D008875:Middle Aged; D009313:National Health Programs; D016012:Poisson Distribution; D012307:Risk Factors; D013997:Time Factors; D002583:Uterine Cervical Neoplasms / Q000401:mortality* / Q000517:prevention & control