Virtual Pooled Registry Approach Improves Cancer Ascertainment
, by Jennifer K. Loukissas, M.P.P.
Accurate cancer incidence and cause-of-death ascertainment is critical for epidemiological research. Without a nationwide registry, population-based cohort studies in the United States often collect these data from participants, through linkage with the National Death Index, or with queries to individual cancer registries. This approach is time-consuming, costly, and subject to error. Investigators in DCEG compared data from these sources and identified several shortcomings. Their conclusions—that a virtual pooled cancer registry could address these gaps—were published in October 2022 in the American Journal of Epidemiology.
Danping Liu, Ph.D., investigator in the Biostatistics Branch, and colleagues used the nationwide U.S. Radiologic Technologists (USRT) Study for this evaluation. Data for over 140,000 participants included questionnaires administered about every 10 years since the mid-1980s and information from death certificates linked with 43 state cancer registries for the follow-up period 1999-2012.
The authors noted that sensitivity varied notably by type of cancer. Considering the 8,858 first primary cancers identified from the registries as a gold standard, overall sensitivity was 46.5 percent from self-reported data alone (ranging from 10.2 percent for the deadliest to 72.4 percent for cancers with the highest survival rates) and 63 percent for data from self-reports and death certificates. Of the false-negative reports, most were due to subjects not completing questionnaires (27.8 percent) and to a substantially lesser extent misreporting (9.2 percent).
Among 90,086 respondents with no record of cancer from registries, self-report and death certificates revealed no record of cancer in 87,831 subjects (specificity of 97.5 percent), but 2,255 subjects reported a cancer that was not identified in any registry (32.6 percent of the subjects resided in states/regions not covered by the participating 43 cancer registries). Among all self-reported cancers (excluding non-melanoma skin cancer), registries identified 66.2 percent with the same cancer (concordance or predictive value ranging from 36.8 percent for melanoma to 81.7 percent and 77.3 percent for breast and prostate cancer, respectively), 5.2 percent with a different cancer, and 28.6 percent with no cancer.
These findings suggest that a nationwide virtual pooled cancer registry supported by the National Cancer Institute will substantially improve the completeness and accuracy of cancer case ascertainment as well as the detail feasible in U.S. epidemiological observational cohort studies.
About the VPR-CLS
The North American Association of Cancer Registries (NAACCR) with funding from the National Cancer Institute, coordinates the VPR-CLS, a single location to facilitate timely access to and use of high-quality cancer surveillance data. An automated, standard linkage methodology and streamlined application process will significantly reduce the level of effort researchers and registries must dedicate to the linkage and approval process.
Liu D et al. Ascertainment of incident cancer by US population-based cancer registries versus self-reports and death certificates in a nationwide cohort study, the US Radiologic Technologists Study. Am J Epidemiol. 2022.