Evaluation of the Swedish Colorectal Cancer Registry: an overview of completeness, timeliness, comparability and validity

Abstract

Background: The Swedish Colorectal Cancer Registry (SCRCR) is a national registry established in 1995 for rectal cancer, and also including colon cancer since 2007. Knowledge of the quality of the registry is vital in order to draw correct conclusions from studies based on the registry. The aim of this study was to assess the completeness, timeliness, comparability and validity of the SCRCR.

Material and methods: Completeness, timeliness and comparability of the registry were estimated. From the SCRCR year 2008, 500 cases were randomly selected to examine the validity of the registry and 486 cases were retrieved. Using hospital patient records as source documents, 130 variables in the SCRCR were reabstracted using the SCRCR registration forms and then compared with the original files.

Result: During the period 2008-2015, the average completeness of the SCRCR was 98.5% for colon cancer and 98.8% for rectal cancer. Timeliness improved between the years 2008 and 2015, with 98% of the patients registered within 12 months for the year 2015. For most of the variables, comparability was estimated to be reproducible and comparable with other registries. Regarding the validity of the registry, when comparing reabstracted data with the original SCRCR data, average agreement was 90%.

Conclusion: The SCRCR can be considered a reliable registry useful for quality assurance and research. Standardization and improvements in journal documentation are needed to improve future evaluation of the source documents.