Linking local cancer registries and national death records: a crucial step for accurate survival data in Saudi Arabia

Abstract

Background: The absence of a link between cancer registries and governmental mortality databases in Saudi Arabia (SA) poses a significant challenge. This disconnect results in incomplete and inaccurate cancer registry survival data, which is crucial for precise survival estimates. While survival data could be updated through direct contact with cancer patients, their families, or physicians, the more accurate and effective method is through computerized linkage. Unfortunately, this method is not currently utilized in SA. Objective: This research aims to assess the knowledge and opinion of the experts in the field of cancer on the importance of having a computerized linkage between cancer registries and Saudi Arabia’s National Death Registry, and secondly, to evaluate the effect of the currently used different follow-up methods on five-year survival estimates. Methods: This study employed a cross-sectional, mixed-methods design. The qualitative component explored experts’ opinions on using record linkage to obtain survival data, assessed through a Likert-scale questionnaire. In the quantitative component, currently available methods to obtain survival data from healthcare systems were evaluated using survival analysis and compared to the active follow-up method. Survival analysis was performed using the Kaplan–Meier method. Survival probabilities were compared using the log-rank test. Results: The survey outcome revealed that 100% (n = 9) of the experts preferred the proposed computerized linkage method to update cancer survival data. The survival analysis using the healthcare system's mortality data without linkage to the National Death Registry results in an overestimated survival rate of 77.9% vs. 70.2%, with a P-value < 0.001. Conclusion: The study's findings underscore the limitations of the current system. The mortality data from the health systems alone cannot be relied upon, as they only report deaths within their system. To obtain accurate and complete data, trustworthy sources such as the National Death Registry must be utilized. The direct (active) follow-up, while effective, is a resource-intensive process that cannot be used for all cancer patients, even at the hospital level. Therefore, adopting the proposed computerized linkage is recommended.