The Value of Clinical Colorectal Cancer Registries in Colorectal Cancer Research: A Systematic Review.

Importance: Clinical colorectal cancer registries (CCCRs) are potentially powerful tools in colorectal cancer research. They are resource intensive, but to our knowledge, no formal review of their value exists. While quality control, clinical audit, and benchmarking are important factors in assessing the value of maintaining CCCRs, they are difficult to quantify. This study focuses on registry research output as a measure of value; the study hypothesizes that CCCRs do not produce sufficient published research output of clinical significance to justify the resources required to maintain them.

Objective: To assess the value of maintaining CCCRs by identifying and characterizing existing CCCRs and measuring their comparative research impact.

Evidence Review: We searched MEDLINE (PubMed) and Google Scholar for articles published from January 1990 to July 2016 that identified multi-institutional CCCRs with peer-reviewed published outcomes. Purely population-based registries were excluded. We then searched the same databases in the same time period for articles that were published by each included CCCR. The articles must have been based on outcomes relating to individual CCCR data. We categorized published outcomes into oncological, surgical, or other outcomes. We measured the research impact of each CCCR using the number of articles, citation index, impact factor, and Altmetric score.

Findings: A total of 18 CCCRs were identified, with sample sizes between 104 and 1 400 000 cases. Data fields, published aims, and outcomes were similar between registries. The most frequently published outcomes related to anastomotic leak following colorectal surgery. The National Cancer Database formed the basis of the highest number of publications (66), the Northern Region Colorectal Cancer Audit Group had the highest median article citation number (28.5), the National Bowel Cancer Audit had the highest median impact factor (4.72), and the National Cancer Database had the highest median Altmetric score (4.5).

Conclusions and Relevance: There is a significant body of colorectal cancer outcomes research generated from the CCCRs. However, given the enormous resources required, the overall research output and impact of CCCRs is low in proportion to the size of the data sets. These registries hold key oncological and surgical outcomes data; focusing on data linkage between registries and developing automated data collection will enable international comparisons in colorectal cancer management and will increase the research impact of CCCRs, thereby increasing their value.