Showing papers by "Hannah K. Weir published in 2014"

Evaluation of North American Association of Central Cancer Registries’ (NAACCR) Data for Use in Population-Based Cancer Survival Studies

Abstract: Follow-up procedures vary among cancer registries in North America. US registries are funded by the Surveillance, Epidemiology, and End Results (SEER) Program and/or the National Program of Cancer Registries (NPCR). SEER registries ascertain vital status and date of last contact to meet follow-up standards. NPCR and Canadian registries primarily conduct linkages with local and national death records to ascertain deaths. Data on patients diagnosed between 2002 through 2006 and followed through 2007 were obtained from 51 registries. Registries that met follow-up standards or, at a minimum, conducted linkages with local and national death records had comparable age-standardized five-year survival estimates (all sites and races combined): 63.9% SEER, 63.1% NPCR, and 62.6% Canada. Estimates varied by cancer site. Survival data from registries using different follow-up procedures are comparable if death ascertainment is complete and all nondeceased patients are presumed to be alive to the end of the study period.

Kidney cancer incidence and mortality among American Indians and Alaska Natives in the United States, 1990-2009.

Abstract: Objectives. We describe rates and trends in kidney cancer incidence and mortality and identify disparities between American Indian/Alaska Native (AI/AN) and White populations.Methods. To improve identification of AI/AN race, incidence and mortality data were linked with Indian Health Service (IHS) patient records. Analysis focused on residents of IHS Contract Health Service Delivery Area counties; Hispanics were excluded. We calculated age-adjusted kidney cancer incidence (2001–2009) and death rates (1990–2009) by sex, age, and IHS region.Results. AI/AN persons have a 1.6 times higher kidney cancer incidence and a 1.9 times higher kidney cancer death rate than Whites. Despite a significant decline in kidney cancer death rates for Whites (annual percentage change [APC] = −0.3; 95% confidence interval [CI] = −0.5, 0.0), death rates for AI/AN persons remained stable (APC = 0.4; 95% CI = −0.7, 1.5). Kidney cancer incidence rates rose more rapidly for AI/AN persons (APC = 3.5; 95% CI = 1.2, 5.8) than for White...

The impact of state-specific life tables on relative survival.

Abstract: There is little debate that measures of survival are a valuable tool available to clinicians, epidemiologists, and public health professionals (1). First proposed by Ederer et al. (2) relative survival compares the survival probabilities of a diseased population (ie, cancer patients) to the survival probabilities of the general population. The resulting value, known as relative survival, is the ratio of observed survival to expected survival which represents the excess mortality associated with a cancer diagnosis. Relative survival is often used as the primary measure in population-based descriptive studies as in general it provides a more reliable estimate of the net survival from cancer than cause-specific survival because it does not rely on death certificate information, which is generally prone to errors in the coding of cause of death and has been shown to have high degrees of misclassification for cancer causes of death (3–5). Unlike crude probabilities of death, net survival represents cancer survival in the absence of competing risks (6). In this issue, Howlader et al.(7) and Mariotto et al. (8) further discuss differences between net and crude survival measures. A key challenge of relative survival is in choosing the population with which to compare to the cancer cohort or in choosing the best life tables to represent the background mortality of the study population. There is a growing body of research questioning the accuracy of relative survival estimates that use life tables from populations that are either not comparable to the cancer cohort [eg, background mortality risk is substantially higher or lower than the cancer cohort, misclassification or unmeasured factors such as race/ethnicity that contribute to differential death rates in the comparison population (9–11)] or when the reference population has a high rate of deaths due to cancer (12). In the United States, researchers using cancer surveillance data from the Surveillance Epidemiology and End Results (SEER) Program often use the US population life tables as the reference group for relative survival estimates, matched by age, sex, race, and calendar year to the cancer cohort (13). The use of US population life tables in and of itself is not necessarily a problem if the cancer cohort has comparable background death rates and characteristics. However, we know that background mortality varies by sex, age, race, and geographic areas as well as socioeconomic status (SES) (14–16). The use of national life tables to calculate state-specific or regional survival has overestimated relative survival in states with lower background death rates and underestimated relative survival in states with higher background death rates (9). Baili et al. (9) reported that even after matching on age, sex, year, and race, relative survival for several US states and regional registry populations were systematically higher when using US-matched life tables compared to the relative survival estimates using SLT [aka: the CONCORD approach (9)]. The only exception was found in Louisiana, which had higher US-matched relative survival estimates as compared to its state-matched relative survival estimates. The authors attributed these differences to the lower background death rates in all states/regions in their study with the exception of Louisiana, which had higher background death rates. Moreover, for early stage prostate and breast cancer, relative survival has been shown to be higher than 100%, indicating that the life tables may not be appropriate for representing survival from other causes when examining cancer survival for these populations (9). With the recent release of the 2000 state decennial life tables by the National Center for Health Statistics (NCHS) (17), this study expands on the work by Baili et al. (9) by comparing five-year relative survival using state- or regionally-matched life tables to US-matched five-year relative survival, focusing on a more contemporary cohort of cancer patients diagnosed from 2000 to 2009. We also examine the underlying characteristics of each state/region to identify potential root causes of variations in survival estimates and assess the variations in survival estimates by age, race, and cancer site for lung and bronchus cancer, colorectal cancer, prostate cancer, and female breast cancer.

Using the National Death Index to identify duplicate cancer incident cases in Florida and New York, 1996-2005.

Abstract: Introduction Cancer registries link incidence data to state death certificates to update vital status and identify missing cases; they also link these data to the National Death Index (NDI) to update vital status among patients who leave the state after their diagnosis. This study explored the use of information from NDI linkages to identify potential duplicate cancer cases registered in both Florida and New York. Methods The Florida Cancer Data System (FCDS) and the New York State Cancer Registry (NYSCR) linked incidence data with state and NDI death records from 1996 through 2005. Information for patients whose death occurred in the reciprocal state (the death state) was exchanged. Potential duplicate cases were those that had the same diagnosis and the same or similar diagnosis date. Results NDI identified 4,657 FCDS cancer patients who died in New York and 2,740 NYSCR cancer patients who died in Florida. Matching identified 5,030 cases registered in both states; 508 were death certificate-only (DCO) cases in the death state's registry, and 3,760 (74.8%) were potential duplicates. Among FCDS and NYSCR patients who died and were registered in the registry of the reciprocal state, more than 50% were registered with the same cancer diagnosis, and approximately 80% had similar diagnosis dates (within 1 year). Conclusion NDI identified DCO cases in the death state's cancer registry and a large proportion of potential duplicate cases. Standards are needed for assigning primary residence when multiple registries report the same case. The registry initiating the NDI linkage should consider sharing relevant information with death state registries so that these registries can remove erroneous DCO cases from their databases.

KidneyCancerIncidenceandMortalityAmongAmerican IndiansandAlaskaNativesintheUnitedStates, 1990-2009

Abstract: Objectives. We describe rates and trends in kidney cancer incidence and mortality and identify disparities between American Indian/Alaska Native (AI/AN) and White populations. Methods. To improve identification of AI/AN race, incidence and mortality data were linked with Indian Health Service (IHS) patient records. Analysis focused on residents of IHS Contract Health Service Delivery Area counties; Hispanics were excluded. We calculated age-adjusted kidney cancer incidence (2001‐2009) and death rates (1990‐2009) by sex, age, and IHS region. Results. AI/AN persons have a 1.6 times higher kidney cancer incidence and a 1.9 times higher kidney cancer death rate than Whites. Despite a significant decline in kidney cancer death rates for Whites (annual percentage change [APC] = ‐0.3; 95% confidence interval [CI] = ‐0.5, 0.0), death rates for AI/AN persons remained stable (APC= 0.4; 95% CI = ‐0.7, 1.5). Kidney cancer incidence rates rose more rapidly for AI/AN persons (APC = 3.5; 95% CI = 1.2, 5.8) than for Whites (APC = 2.1; 95% CI= 1.4, 2.8).