Analysis of multiple causes of death: a review of methods and practices

Background Research and reporting of mortality indicators typically focus on a single underlying cause of death selected from multiple causes recorded on a death certificate. The need to incorporate the multiple causes in mortality statistics - reflecting increasing multimorbidity and complex causation patterns - is recognised internationally. This review aims to identify and appraise relevant multiple cause analytical methods and practices. Methods We searched Medline, PubMed, Scopus and Web of Science from inception to December 2020 without language restrictions, supplemented by consultation with international experts. Eligible articles included those analysing multiple causes of death from death certificates. The process identified 4,080 articles; after screening, 434 full texts were reviewed. Results Most reviewed articles (77%, n=332) were published since 2001. The majority examined mortality by “any-mention” of a cause of death (87%, n=377) and assessed pairwise combinations of causes (56%, n=245). Recently emerging (since 2001) were applications of methods to group deaths based on common cause patterns using, for example, cluster analysis (2%, n=9), and the application of multiple cause weights to re-evaluate mortality burden (1%, n=5). Multiple cause methods applied to specific research objectives are described for recently emerging approaches. Conclusion This review confirms rapidly increasing international interest in the analysis of multiple causes of death and provides the most comprehensive overview of methods and practices to date. Available multiple cause methods are diverse but suit a range of research objectives, that with greater data availability and technology could be further developed and applied across a range of settings.