title: How complete and accurate are cancer registrations notified by the National Health Service Central Register for England and Wales?
abstract: OBJECTIVE
  To assess the completeness and accuracy of notification of cancers by the National Health Service Central Register (NHSCR) for England and Wales.
  
  
  METHODS
  Comparison of 720 cancer registrations ascertained from NHSCR up to May 1999 with those ascertained for the same cohort from six other sources and a pathology review of the NHSCR cancer registrations.
  
  
  METHODS
  People born in Cumbria, north west England, 1950-89, and diagnosed with cancer throughout the UK, 1971-1989.
  
  
  RESULTS
  Cancer diagnoses notified by NHSCR differed substantially from those determined by this pathology review for 47 of the 688 notified cases reviewed (7%; 95% CI 5%, 9%). Over one third of these discrepancies were attributable to failures in data capture or coding by the cancer registration system and almost half to changes in diagnosis; 26 of the 47 discrepant cases were reclassified as non-malignant and 21 as malignancies but with a substantially different diagnosis. The 694 confirmed malignancies represented 94% (95%CI 92%, 95%) of the 740 cancers ascertained from all sources.
  
  
  CONCLUSIONS
  It is estimated that the cancer registration system missed at least 10% (95%CI 6%, 15%) of all incident cases of malignant disease. Without additional ascertainment from multiple sources and diagnostic review, it would be incautious to use NHSCR cancer registrations as the sole basis of an epidemiological study.
authors.affiliation: Department of Child Health, University of Newcastle, Royal Victoria Infirmary, Queen Victoria Road, Newcastle upon Tyne NE1 4LP, UK. healther.dickinson@ncl.ac.uk
authors.forename: H O
authors.initials: HO
authors.lastname: Dickinson
authors.forename: J A
authors.initials: JA
authors.lastname: Salotti
authors.forename: P J
authors.initials: PJ
authors.lastname: Birch
authors.forename: M M
authors.initials: MM
authors.lastname: Reid
authors.forename: A
authors.initials: A
authors.lastname: Malcolm
authors.forename: L
authors.initials: L
authors.lastname: Parker
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003953:Diagnosis-Related Groups; D004739:England / Q000453:epidemiology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000175:diagnosis / Q000453:epidemiology*; D012042:Registries / Q000592:standards*; D013222:State Medicine; D014852:Wales / Q000453:epidemiology