We report a new method of estimating the completeness of cancer registration, in which the proportions of unregistered patients are derived from the time distributions of three probabilities, each of which can be directly estimated from the registry's own data – the probabilities of survival, of registration of the cancer during the patient's life, and of the mention of cancer on the death certificate of a cancer patient who dies. This method allows completeness to be assessed routinely by factors such as age, sex, geographical area and tumour type. © 2000 Cancer Research Campaign

Objectives Non–small-cell lung cancer (NSCLC) patient survival depends on a number of factors, including early diagnosis and initiation of treatment. Standard treatment options for patients with NSCLC include surgery, radiation therapy, and chemotherapy. The objective of this study was to evaluate the impact that the initiation of timely treatment has on patient survival among a cohort of privately insured patients with NSCLC in South Carolina. Methods Data for the study were retrospectively obtained from the South Carolina Central Cancer Registry and the state health plan Blue Cross and Blue Shield claims. Patients were diagnosed as having NSCLC between January 1, 2005 and December 31, 2010, were aged 18 years or older, and were covered under the state health plan for at least 1 year before diagnosis. The final study sample included 746 patients. Kaplan-Meier curves and Cox proportional hazard modeling were conducted to examine factors associated with survival, stratified by stage at diagnosis. Results The majority in the study cohort (80%) received timely (≤6 weeks) rather than untimely (>6 weeks) care (20%). The mean survival time for patients receiving timely treatment by stage was 36.9, 27.1, and 12.4 months for localized, regional, and distant metastasis, respectively. The mean survival time for patients receiving untimely care by stage was 39.4, 33.8, and 25.2 months for localized, regional, and distant metastasis, respectively. Among patients with NSCLC in the distant metastasis stage, those receiving timely treatment experienced significantly decreased survival (hazard ratio 2.2) in comparison to those receiving untimely care. Conclusions Initiation of treatment within 6 weeks is not associated with greater survival time across all stages of cancer (localized, regional, and distant metastasis). Additional research is needed to examine the impact of other treatment quality metrics on the survival of patients with NSCLC, different time thresholds for treatment initiation that may be more meaningful to survival among patients with NSCLC, and timely care among patients with NSCLC in other geographic areas and populations.