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

Abstract

Objective. Recently, the first mortality data from the Göteborg Randomized Population-based Prostate Cancer Screening Trial showed a 44% reduction in prostate cancer (PC)-specific mortality as a result of screening with prostate-specific antigen (PSA). As death of PC is the main endpoint, an accurate determination of the cause of death (COD) is crucial. The aim of this study was therefore to investigate the accuracy of death certificates of men in the Göteborg Randomized Population-based Prostate Cancer Screening Trial. Material and methods. Men with a PC diagnosis and who died within the study period (1995–2008) were included. Relevant medical information, including death certificate, was collected. An independent COD committee reviewed the material following a flowchart to classify the COD. The committee's decision was compared with the COD on the death certificate. Results. Of the 285 men included in the study, 278 men were eligible for a comparative analysis. The committee and the death certificates agreed on PC as the underlying COD in 116 men and causes other than PC in 151. There were 11 discordant cases, for an overall agreement of 96%. Men with PC in the screening group had, compared with the control group, a significantly lower PC-specific mortality but did not differ in non-PC-specific mortality. Conclusion. This study concludes that Swedish death certificates are of high accuracy and can be used for endpoint evaluation in screening studies for PC.

Key Words::

• Causes of death
• epidemiology
• mortality
• prostate cancer
• screening

Acknowledgements

Grants have been received from the Swedish Cancer Society (contract numbers 10 0108 and 08 0315).We thank Helén Ahlgren, data manager and study secretary, and Maria Nyberg, study nurse, for their excellent contribution to data collection. We also want to express our gratitude towards the members of the COD committee; Bo Johan Norlén, Professor Emeritus in Urology, Silas Pettersson, Professor Emeritus in Urology, and Eberhard Varenhorst, Professor Emeritus in Urology.

Declaration of interest: Dr Hugosson reports receiving lecture fees from GSK and Abbot. Dr Stranne reports receiving lecture fees from Astellas and Abbot. All other authors declare that they have no conflicts of interest.