title: Appropriateness of the standard mortality/incidence ratio in evaluation of completeness of population-based cancer registry data.
abstract: BACKGROUND
  The magnitude of differences in mortality incidence (M:I) ratios derived from the national mortality source and those derived from cancer registry (CR) databases may be used to determine associated factors.
  
  
  METHODS
  All information on cancer incidence cases and mortality cases from January 1, 2003 to December 31, 2007 were retrieved from 5 population-based cancer registries in four regions of Thailand. Two sources of mortality were used: death cases within the cancer registries and mortality statistics obtained from the Ministry of Public Health (MOPH). Plots of percentage M:I ratios from cancer registry databases and from national mortality sources against 1 minus 5 years relative survival (1-5yrRS) were used to visualize the correlation between the two mortality sources. A Poisson regression model was used to determine the influence of cancer sites and registries on the M:I ratio/[1-5yrRS].
  
  
  RESULTS
  There was high variability between the standard M:I ratio derived from national mortality compared with 1-5 year RS. The factors affecting M:I ratios are sources of mortality data and misclassification of topographic site as the cause of death.
  
  
  CONCLUSIONS
  Use of the M:I ratio is not recommended to evaluate completeness of cancer registry data when the quality of mortality data is poor.
authors.affiliation: Prince of Songkla University, Songkhla, Thailand. krisuw@kku.ac.th
authors.forename: Krittika
authors.initials: K
authors.lastname: Suwanrungruang
authors.forename: Hutcha
authors.initials: H
authors.lastname: Sriplung
authors.forename: Somnuk
authors.initials: S
authors.lastname: Temiyasathit
authors.forename: Narate
authors.initials: N
authors.lastname: Waisri
authors.forename: Karnchana
authors.initials: K
authors.lastname: Daoprasert
authors.forename: Supot
authors.initials: S
authors.lastname: Kamsa-Ard
authors.forename: Cheamchit
authors.initials: C
authors.lastname: Tasanapitak
authors.forename: Edward
authors.initials: E
authors.lastname: McNeil
mesh_terms: D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D009369:Neoplasms / Q000453:epidemiology* / Q000401:mortality*; D011379:Prognosis; D012042:Registries / Q000592:standards* / Q000706:statistics & numerical data*; D015996:Survival Rate; D013785:Thailand / Q000453:epidemiology