Comparison of Epidemiological Estimates for 19 Cancer Types Using Electronic Health Record Databases in England: An...

To compare epidemiological estimates of 19 different cancer types in Clinical Practice Research Datalink (CPRD) Aurum and CPRD General Practice Online Database (GOLD) databases against linked secondary data sources in England to understand best use of these data sources for research.

The source population comprised patients in CPRD Aurum or GOLD (separately) who were eligible for linkage to Cancer Registry (CR), Hospital Episode Statistics (HES), and Office for National Statistics (ONS). We selected patients who had an incident cancer diagnosis recorded in ≥1 data sources (CPRD Aurum or GOLD, HES, CR) between January 1, 2011 and December 31, 2018. We estimated incidence rates (IR) and counts by cancer type and data source, and survival probability by cancer type among patients with an ONS death record recorded between January 1, 2011 and April 30, 2020.

The highest incident case capture resulted from CPRD Aurum or GOLD linked to HES and CR. In the fully linked CPRD Aurum-HES-CR and CPRD GOLD-HES-CR datasets, cancers typically diagnosed and managed in primary care (eg, breast, prostate, and lung) had the highest IRs and more complete case capture compared with other data sources, whereas HES and CR had higher IRs for cancers diagnosed in secondary care settings (eg, gastric, renal, and bladder). Cancers with broad definitions (eg, head and neck) had wider variations in IRs across data sources than cancers with narrower definitions. Survival estimates were generally higher for cancer-related deaths versus all-cause deaths.

Findings highlight variation in cancer recording across different data sources. Researchers using CPRD data should assess the benefit of incorporating linked data on a study-by-study basis. For studies of breast, prostate, and lung cancers, CPRD Aurum or GOLD alone may be sufficient; however, linkage to HES and/or CR is recommended where a more complete case capture is required.