Objective: Population-based cancer registries provide an excellent source of data for cancer surveillance and research. However, delays in reporting and processing can affect the accuracy of incidence rates and the availability of cases for research. This study was designed to describe factors related to delays in availability of cancer cases for epidemiologic analysis.
Methods: We identified all cancer cases diagnosed in 2000 and reported to the California Cancer Registry by August 2004. We analyzed factors associated with time to availability, defined as the time from diagnosis until the time the case was available for research.
Results: A total of 137,270 cancer cases were reported during the study period. The median time to availability for all cases was 382 days. Forty-five percent of cases were available within the first 12 months and 96% were available within 24 months after diagnosis. Cases reported by hospitals had the shortest time to availability (373 days) followed by doctors' offices and laboratories. Melanoma and prostate cancers had longer times to be available than other types of cancer. Time to availability varied by geographic region, but differences by age, gender, race and stage at diagnosis were minimal or non-significant.
Conclusion: Strategies are needed to improve timeliness without sacrificing quality and completeness.