Research Article| Volume 51, ISSUE 1, P101-111, January 2015

Evaluation of data quality in the National Prostate Cancer Register of Sweden

Published:November 20, 2014DOI:



      Data in cancer quality registers are increasingly used for quality assurance, benchmarking, and research.

      Materials and methods

      Data in the National Prostate Cancer Register (NPCR) of Sweden were evaluated for completeness, timeliness, comparability and validity. Completeness and timeliness were assessed by cross-linkage to the Swedish Cancer Register, comparability was examined by comparing registration routines in NPCR with national and international guidelines, and validity was assessed by re-abstraction of data from medical charts for 731 men diagnosed with prostate cancer (Pca) in 2009. Furthermore, data on treatment were validated by record linkage to the Swedish Patient Register and The Prescribed Drug Register.


      NPCR captured 98% of Pca cases in the Cancer Register and the mean value for completeness of the 48 evaluated variables was 90% (range 64–100%). Timeliness increased substantially from 2008 to 2012 with 95% of cases reported within 12 months after diagnosis in 2012. NPCR complied with national and international coding routines. Overall, the agreement between original data and re-abstracted data from 731 charts was high. For example, the correlation between original and re-abstracted data was 1.00 for date of surgery, and 0.97 for serum levels of prostate specific antigen and exact agreement was 97% for Gleason score at biopsy, 83% for clinical local T stage and more than 95% of the androgen deprivation therapies registered in NPCR had a corresponding filled prescription.


      Record linkages with other data sources and re-abstraction of data showed that data quality in NPCR is high.


      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to European Journal of Cancer
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Armstrong B.K.
        The role of the cancer registry in cancer control.
        Cancer Causes Control. 1992; 3 ([Epub 1992/11/01]): 569-579
        • Parkin D.M.
        The role of cancer registries in cancer control.
        Int J Clin Oncol. 2008; 13 ([Epub 2008/05/09]): 102-111
        • Liu W.L.
        • Kasl S.
        • Flannery J.T.
        • Lindo A.
        • Dubrow R.
        The accuracy of prostate cancer staging in a population-based tumor registry and its impact on the black-white stage difference (Connecticut, United States).
        Cancer Causes Control. 1995; 6 ([Epub 1995/09/01]): 425-430
        • Polissar L.
        • Feigl P.
        • Lane W.W.
        • Glaefke G.
        • Dahlberg S.
        Accuracy of basic cancer patient data: results from an extensive recoding survey.
        J Natl Cancer Inst. 1984; 72 ([Epub 1984/05/01]): 1007-1014
        • Izquierdo J.N.
        • Schoenbach V.J.
        The potential and limitations of data from population-based state cancer registries.
        Am J Public Health. 2000; 90 ([Epub 2000/05/09]): 695-698
        • Seddon D.J.
        • Williams E.M.
        Data quality in population-based cancer registration: an assessment of the Merseyside and Cheshire Cancer Registry.
        Br J Cancer. 1997; 76 ([Epub 1997/01/01]): 667-674
      1. Parkin DM CV, Ferlay J, Galceran J, Storm HH, Whelan SL, editors. Comparability and quality control in cancer registration. Lyon IARC (WHO) and IACR, 1994.

        • Bray F.
        • Parkin D.M.
        Evaluation of data quality in the cancer registry: principles and methods. Part I: comparability, validity and timeliness.
        Eur J Cancer. 2009; 45: 747-755
        • Parkin D.M.
        • Bray F.
        Evaluation of data quality in the cancer registry: principles and methods Part II. Completeness.
        Eur J Cancer. 2009; 45: 756-764
        • Van Hemelrijck M.
        • Wigertz A.
        • Sandin F.
        • Garmo H.
        • Hellstrom K.
        • Fransson P.
        • et al.
        Cohort profile: the National Prostate Cancer Register of Sweden and Prostate Cancer data Base Sweden 2.0.
        Int J Epidemiol. 2013; 42: 956-967
      2. Sobin LH, Wittekind C, International Union Against Cancer. TNM classification of malignant tumours. 6th ed. New York: Wiley-Liss; 2002. xxiii, p. 239.

      3. NPCR. The National Prostate Cancer Register of Sweden (in Swedish). 2014 [2014-07-10, date last accessed]; Available from: <>.

      4. Cancer incidence in five continents. Volume IX. IARC scientific publications. 2008;(160):1–837. [Epub 2008/01/01].

      5. INCA. Information network for cancer care (in Swedish). 2014 [2014-07-10, date last accessed]; Available from: <>.

        • Barlow L.
        • Westergren K.
        • Holmberg L.
        • Talback M.
        The completeness of the Swedish Cancer Register: a sample survey for year 1998.
        Acta Oncol. 2009; 48: 27-33
        • Heidenreich A.
        • Bastian P.J.
        • Bellmunt J.
        • Bolla M.
        • Joniau S.
        • van der Kwast T.
        • et al.
        Guidelines on prostate cancer.
        Eur Urol. 2014; 65: 124-137
        • Wettermark B.
        • Hammar N.
        • Fored C.M.
        • Leimanis A.
        • Otterblad Olausson P.
        • Bergman U.
        • et al.
        The new Swedish Prescribed Drug Register-opportunities for pharmacoepidemiological research and experience from the first six months.
        Pharmacoepidemiol Drug Saf. 2007; 16: 726-735
        • Sobin L.H.
        • Compton C.C.
        TNM seventh edition: what’s new, what’s changed: communication from the International Union Against Cancer and the American Joint Committee on Cancer.
        Cancer. 2010; 116: 5336-5339
      6. Socialstyrelsen. The National Board of Health and Welfare: The Prescribed Drug Register (in Swedish). 2008 [2014-07-10, date last accessed]; Available from: <>.

        • Ingelsson E.
        • Arnlov J.
        • Sundstrom J.
        • Lind L.
        The validity of a diagnosis of heart failure in a hospital discharge register.
        Eur J Heart Fail. 2005; 7: 787-791
        • Hammar N.
        • Alfredsson L.
        • Rosen M.
        • Spetz C.L.
        • Kahan T.
        • Ysberg A.S.
        A national record linkage to study acute myocardial infarction incidence and case fatality in Sweden.
        Int J Epidemiol. 2001; 30: S30-S34
        • Godtman R.
        • Holmberg E.
        • Stranne J.
        • Hugosson J.
        High accuracy of Swedish death certificates in men participating in screening for prostate cancer: a comparative study of official death certificates with a cause of death committee using a standardized algorithm.
        Scand J Urol Nephrol. 2011; 45: 226-232
        • Fall K.
        • Stromberg F.
        • Rosell J.
        • Andren O.
        • Varenhorst E.
        Reliability of death certificates in prostate cancer patients.
        Scand J Urol Nephrol. 2008; 42: 352-357
      7. Socialstyrelsen. The National Board of Health and Welfare: Reporting to national quality and health care registers – comparison of completeness (in Swedish). 2013 [2014-07-10, date last accessed]; Available from: <>.

      8. Bröstcancerregistret. Yearly report for the Swedish National Breast Cancer Register 2012 (in Swedish). 2012 [2014-07-10, date last accessed]; Available from: <>.

        • Tomic K.
        • Berglund A.
        • Robinson D.
        • Hjälm-Eriksson M.
        • Carlsson S.
        • Lambe M.
        • et al.
        Capture rate and representativity of The National Prostate Cancer Register of Sweden.
        Acta Oncol. 2014; ([E-pub])
        • Sigurdardottir L.G.
        • Jonasson J.G.
        • Stefansdottir S.
        • Jonsdottir A.
        • Olafsdottir G.H.
        • Olafsdottir E.J.
        • et al.
        Data quality at the Icelandic Cancer Registry: comparability, validity, timeliness and completeness.
        Acta Oncol. 2012; 51: 880-889
        • Larsen I.K.
        • Smastuen M.
        • Johannesen T.B.
        • Langmark F.
        • Parkin D.M.
        • Bray F.
        • et al.
        Data quality at the Cancer Registry of Norway: an overview of comparability, completeness, validity and timeliness.
        Eur J Cancer. 2009; 45: 1218-1231
        • Sandblom G.
        • Dufmats M.
        • Olsson M.
        • Varenhorst E.
        Validity of a population-based cancer register in Sweden–an assessment of data reproducibility in the South-East Region Prostate Cancer Register.
        Scand J Urol Nephrol. 2003; 37: 112-119