Evaluation of service screening for breast cancer by clinical breast examination using regional cancer registry data

MATERIALS: (1) Screening test: The study utilized data from a regional cancer-screening center from April 1, 1997, to December 31, 1998. A total of 51,700 women underwent screening at this center during this period. All incident cases of breast cancer in these women were derived from the files of the Yamagata Prefectural Cancer registry and sensitivity, specificity and positive predictive value were then estimated. False negative cases were defined as occurring in women who tested negative but were registered as having breast cancer in the cancer registry within 12 months after screening. (2) Effectiveness of screening: The target population comprised female cases with breast cancer registered in the Yamagata Prefectural Cancer Registry from January 1, 1989 to December 31, 1998. During this period, a total of 2,746 cases were registered. Survival probabilities for breast cancer cases were estimated according to method of detection using Kaplan-Meier method. Overall survival probability of the screen-detected group was compared with the not screen-detected group using the log-rank test. Point estimates of 5- and 9-year survival rates between groups were compared using z statistics. RESULTS: (1) Screening detected 27 breast cancer cases, while 31 false negative cases were identified. Sensitivity, specificity and positive predictive value were 46.6% (95% confidence interval (95% CI), 33.3-60.1%), 97.3% (95% CI, 97.2-97.5%) and 1.9% (95% CI, 1.3-2.8%), respectively. (2) Overall survival rate for the screen-detected group was significantly higher than that for the not screen-detected group (P<0.001), with 11.6% (95% CI, 8.0-15.2%) and 13.1% (95% CI: 5.3-20.8%) differences in 5-year and 9-year survival probabilities, respectively. CONCLUSION: Cancer screening by clinical breast examination in Yamagata has improved survival from breast cancer for females. However, the screening sensitivity is insufficient for effective mass screening purposes.     

Breast cancer incidence using administrative data: correction with sensitivity and specificity

ObjectiveTo estimate breast cancer incidence in the general population using a method that corrects for lack of sensitivity and specificity in the identification of incident breast cancer in inpatient claims data.Study Design and SettingsTwo-phase study: phase 1 to identify incident cases in claims data, and phase 2 to estimate sensitivity and specificity in a subset of the population. Two algorithms (1: principal diagnosis; 2: principal diagnosis + specific surgery procedures) were used to identify incident cases in claims of women aged 20 years or older, living in a French district covered by a cancer registry. Sensitivity and specificity were estimated in one district and used to correct incident cases identified.ResultsThe sensitivity and specificity for algorithms 1 and 2 were 69.0% and 99.89%, and 64.4% and 99.93%, respectively. In contrast to specificity, the sensitivity for both algorithms was lower for women younger than 40 years and older than 65 years. Cases reported by cancer registries were closer to cases identified with algorithm 2 (?3.2% to +20.1%) and to corrected numbers with algorithm 1 (?1% to +15%).ConclusionTo obtain reliable estimates of breast cancer incidence in the general population, sensitivity and specificity, which reflect medical and coding practice variations, are necessary.     

A team approach to improving colorectal cancer services using administrative health data

Background  

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in Canada and accounts for 11.9% of all cancer-related mortality. Fortunately, previous studies have provided evidence of improved outcomes from access to timely and appropriate health services along the disease trajectory in CRC. As a result, the CIHR/CCNS Team in Access to Colorectal Cancer Services in Nova Scotia (Team ACCESS) was created to build colorectal cancer (CRC) research capacity in Nova Scotia (NS) and to study access to and quality of CRC services along the entire continuum of cancer care.     

Social class and the black/white crossover in the age-specific incidence of breast cancer: a study linking census-derived data to population-based registry records

An unexplained racial crossover in breast cancer rates in the United States has been apparent since 1969: among women over age 40 years, the rate is higher among white compared with black women, while among women under age 40, the reverse is true. To explore the contribution of social class to this phenomenon, the present study used 1980 census block-group data to generate population-based age-specific breast cancer rates stratified by race and class. Cancer data included all black women (n = 405) and white women (n = 4,259) diagnosed with primary breast cancer during 1979-1981 in the San Francisco Bay Area Resource for Cancer Control registry. Among women under age 40, the black/white incidence ratio among women from predominantly working class block-groups was 1.08 (95% confidence interval (CI) 0.74-1.56), but among those from non-working class block-groups, the black/white ratio equaled 1.96 (95% CI 1.17-3.26). Among women age 40 years or over, the black/white incidence ratio among women from working class block-groups was 0.78 (95% CI 0.68-0.89), but was 0.98 (95% CI 0.78-1.23) among women from non-working class block-groups. These findings underscore the class-based nature of the observed crossover and pose a challenge to accepted theories of breast cancer etiology. Possible risk factors contributing to these findings are discussed, including induced abortion and oral contraceptive use prior to first full-term pregnancy.     

A comparative study of prevalence‐based incidence estimation techniques with application to dementia data in Germany

Dementia is becoming a major health burden, which is mainly due to the increasing life expectancy in many developed countries. To describe the disease progression of individuals, multistate models are generally appropriate tools. These models allow the individuals to move along a path consisting of a finite number of disease states. We consider a simplifying illness–death model in which the subjects progress through the states healthy, diseased and dead. We use this model to study analytic relationships between the prevalence, incidence and mortality rates of irreversible diseases that have been applied in the past. One of these approaches is a rather recently proposed technique based on an ordinary differential equation (ODE). We conduct a simulation study to compare the performance of two suggested numerical approximations of this ODE with three alternative techniques, the common goal of which is to estimate age‐specific incidence from cross‐sectional information. The quality of the estimation methods is further explored using data on dementia in Germany. In the simulation scenarios as well as in the dementia data setting, the ODE method turns out to be the predominant technique with regard to the quality of the estimation of the known incidence regimes. Copyright © 2015 John Wiley & Sons, Ltd.     

Cumulative damage models in cancer epidemiology: application to human incidence and mortality data

Cumulative damage models are a special class of mathematical models within reliability theory that describe the probability of failure of a given system under the impact of a damaging environment. Though originally introduced to handle wear and tear processes, their concepts can easily be interpreted in terms of the epidemiologic aspects of human carcinogenesis. This paper introduces the new approach and demonstrates its applicability to human cancer incidence and mortality data from Denmark and the Federal Republic of Germany. A slight simplification of the originally stochastic model provides an explicit formula for the relative risk between different populations, which predicts that this basic measure used in cancer epidemiology may have to be considered age-dependent in contrast to a widely used practice which, for convenience, postulates age-independent relative risks. A comparison with empirical data reveals that the concept of age-dependent relative risks is not inconsistent with real world examples of cancer incidence. Thus, some basic assumptions and concepts of epidemiology concerning carcinogenesis and strategies for data analysis may require reconsideration.     

Using VA administrative data to measure colorectal cancer screening adherence among average-risk non-elderly veterans

This study represents a new application of Veterans Affairs (VA) administrative data for measuring VA system-wide performance of colorectal cancer (CRC) screening adherence among veterans at average-risk for CRC. Our new measurement has two features: it is specifically designed for average-risk populations and is applied repeatedly at the veteran level each year over the study period. Using 1997–2007 VA administrative data, we developed an algorithm that first constructed 7 independent cohorts of average-risk veterans eligible for CRC screening, one for each year from 2001 to 2007, and then appended the seven cohorts together to form 2001–2007 veteran-level panel data. Veterans in a cohort for a given year were considered adherent if they received fecal occult blood test (FOBT) during that given year, or received flexible sigmoidoscopy (FS), double-contrast barium enema (DCBE), or colonoscopy during that given year or the 4 previous years. The main analysis shows that VA CRC screening rates increased from 30.11% in 2001 to 35.51% in 2004, but declined to 31.54% in 2007. Among the screened, the proportion adherent to colonoscopy increased over the 7-year period while the proportion adherent to FOBT, FS, or DCBE decreased during the same period. Sensitivity analyses, including use of a 10-year retrospective window for determining the screening adherence of colonoscopy, show the robustness of the main analysis. This new algorithm demonstrates that VA administrative data may be used for assessing VA performance of CRC screening adherence of average-risk veterans. Furthermore, our panel data may enhance understanding of factors associated with CRC screening adherence.     

Myocardial infarction in 3 French regions: comparison of incidence and mortality in 1985

In 1985, the age-standardized (25-64) attack rate (per 100,000) for myocardial infarction, among men was 240 in the Bas-Rhin, 219 in the Haute-Garonne and 231 in the urban community of Lille and among women, respectively, 58, 28 and 51. The mortality rate for men (per 100,000) was 66 (Bas-Rhin), 57 (Haute-Garonne), 69 (Lille) and among women 18, 7 and 14. Among women, these differences are significant. A regional significant difference appears among men when cases with insufficient data are included. The sex ratio (men/women) was higher in the Haute-Garonne. 38% of death cases occurred within one hour, 76% within one day, and 89% in the first week after the first symptoms. The case fatality rate at 28 days does not differ significantly between the three registries (from 26% to 30%). The highest case fatality rates were observed in patients aged 25-34 and 55-64. The frequency of previous history of cardiovascular disease and the management of the cases were not different between regions. Diagnostic criteria problems are discussed.     

Estimation of trends in cancer incidence in a population-based cancer registry

To evaluate trends in cancer incidence adjusted for completeness of registration in a population-based cancer registry, we analyzed the data of incidence and mortality in the Aichi Cancer Registry from 1979 to 1986 and recalculated age-adjusted incidence rates (AAIRs) at the lowest completeness of registration through the study period by excluding reported cases from the registration randomly. The results were as follows: 1) The AAIRs for male stomach cancer and rectal cancer in both sexes, which did not decrease or rather increased using the original incidence figures, showed a clear decrease after adjustment. 2) The AAIRs for female stomach and uterine cancers, which also showed decreases in the original incidence, showed more marked decreases. 3) The marked increases observed for the AAIRs for colon and breast cancers in the original incidence were attenuated by about 50%. 4) The AAIRs for liver and lung cancers were also affected somewhat by the adjustment for completeness of registration. 5) Trends in the AAIRs after adjusting for completeness of registration were virtually the same as those for age-adjusted mortality rates.     

The validity of hospital administrative data in monitoring variations in breast cancer surgery.

To assess the validity of using hospital administrative data to measure variations in surgery for early-stage breast cancer, ICD-9-CM coded information was compared with corresponding tumor registry data for 1293 breast cancer patients undergoing lumpectomy or mastectomy at a tertiary referral center from January 1989 to October 1993. Relative to "gold standard" tumor registry data, the administrative data proved 83.4% sensitive and 80.4% specific in identifying women with localized disease who would be potential candidates for lumpectomy. The proportion of women with localized disease undergoing lumpectomy in groups defined by race and insurance status was nearly identical, whichever data were used. Administrative data, which is often readily and publicly available, may be useful in studying variations in breast cancer treatment in key demographic groups.     

Using cancer registry data for survival studies: the example of the Ontario Cancer Registry

Background and ObjectivesThe Ontario Cancer Registry (OCR) is a population-based tumor registry created to provide data for epidemiologic research and for cancer surveillance. Recently it has been used for health services research. The objective of this project was to assess the quality of the OCR data that is used in survival analysis.Methods and DesignClinical information for 898 patients with squamous carcinoma of the head and neck including index tumor site, date of diagnosis, vital status, date of death, and cause of death from a prospective database at the Kingston Regional Cancer Center is compared to the same data elements in the OCR for the same patients.ResultsThere is no statistically significant difference in disease-specific survival between the information from the two databases (log rank P = .89). The OCR captured and correctly assigned index tumor site for 81.4% (detection rate). The site assignment was accurate 90.9% of the time (confirmation rate), there was agreement on vital status (dead vs. alive) for all but one patient, and there was excellent agreement on date of death. However, cause of death (cancer vs. noncancer) based on death certificates had a 31% error rate.ConclusionResearchers can be confident in the survival analysis generated from data in this registry, but need to be aware of potential sources of error.     

Spatial analysis of lung,colorectal, and breast cancer on Cape Cod: An application of generalized additive models to case-control data

Background  

The availability of geographic information from cancer and birth defect registries has increased public demands for investigation of perceived disease clusters. Many neighborhood-level cluster investigations are methodologically problematic, while maps made from registry data often ignore latency and many known risk factors. Population-based case-control and cohort studies provide a stronger foundation for spatial epidemiology because potential confounders and disease latency can be addressed.     

Predicting the absolute risk of dying from colorectal cancer and from other causes using population-based cancer registry data

This paper describes how population cancer registry data from the Surveillance, Epidemiology, and End Results program of the National Cancer Institute can be used to develop a prognostic model to predict the absolute risk of mortality from cancer and from other causes for an individual with specific covariates. It incorporates previously developed methods for competing risk modeling along with an imputation method to address missing cause of death information. We illustrate these approaches with colorectal cancer and evaluate the model discriminatory and calibration accuracy by time-dependent area under the receiver operating characteristic curve and calibration plot.     

A feasibility study to assess the validity of administrative data sources and self-reported information of breast cancer survivors

Background

Cancer survivorship has increasingly become the focus of research due to progress in early detection and advancements in the therapeutic approach, but high-quality information sources for outcomes, potential confounders and personal characteristics present a challenge. Few studies have collected breast cancer care data from mixed data sources and validated them, and to the best of our knowledge, none so far have been conducted in Israel, where National Health Insurance Law assures universal health care, delivered through four health care funds with computerized administrative, pharmaceutical and medical databases.This validation study is aimed to assess the accuracy and completeness of information on cancer care and health outcomes using several research tools, before embarking on a full-scale study aimed to evaluate the long-term treatment-related health adverse outcomes in a cohort of breast cancer survivors.

Methods

One hundred twenty randomly sampled female patients diagnosed with primary breast cancer in years 2000–2010 in northern Israel, who are members of the “Leumit” healthcare fund, were included. Data sources included “Leumit” medical records, the National Cancer Registry and a self-report questionnaire. The questionnaire was completed by 99 % of the women contacted. The accuracy of the information regarding cancer care was assessed with the reference standard set as one of the research tools, varying per the characteristic being under investigation. For example: health outcomes and medical history were validated against “Leumit” medical records, while construct validity of the self-reported questionnaire served to assess the prevalence of chronic pain. Agreement, predictive values, correlations, and internal consistency were calculated. Logistic regression models were constructed to assess potential predictors of correct responses.

Results

The overall level of agreement (Kappa) was almost perfect for demographics and outcomes, above 0.8 for treatments and chronic pain, while only fair to moderate for most of the self-reported medical history. Correct responses of medical history were associated with Jewish ethnicity, recency of breast cancer diagnosis, and family history of cardiovascular disease. The internal consistency of the quality-of-life scale was above 0.9.

Conclusion

In the absence of a national registry for cancer care, a mixed methodology for data collection is the most complete source.

Trial registration

Trial registration number Not available. This is an observational study with prospective data collection and no intervention; therefore, trial registration number is not required.

     

Reliability of data of the Thames cancer registry on 673 cases of colorectal cancer: effect of the registration process.

OBJECTIVE--To measure the reliability of data collected by the Thames cancer registry and to identify factors in the registration process affecting reliability. DESIGN--A retrospective study of data from the registry, including death certificate only registrations, and hospital case notes on cases of colorectal cancer diagnosed in 1983 or 1988. SETTING--Four districts in South Thames region. SUBJECTS--673 cases of colorectal cancer in resident patients. MAIN MEASURES--Dates of birth, diagnosis of cancer, and death; sex; tumour site; whether treatment was given; type of treatment; and district of residence. RESULTS--Among the 416 (62%) case notes retrieved, including 66 death certificate only registrations, full or high agreement between registry data and hospital notes was recorded for sex, district of residence, and dates of birth and death. Only 12% of cases had the same date of diagnosis, which may be due to failure of registry policy. Lower agreement rates occurred for tumour site (87%), whether treatment occurred (84%), and treatments administered (80%, 1983; 72%, 1988). 20% of surgical treatments and 37% of adjuvant therapy, radiotherapy, and chemotherapy were not recorded by the registry. Disagreements were common among death certificate only registrations. Such registrations accounted for 16(32%) disagreements over tumour site, 33(41%) major disagreements over date of diagnosis (difference > 30 days), and 47(44%) disagreements over treatment. In 65 cases the registry failed to capture all treatments carried out within the six month follow up period, 38(58%) of which were for death certificate only registrations. In 36% of death certificate only registrations the patients survived more than one year from diagnosis, indicating a failure of registry policy over retrospective follow up. CONCLUSIONS--Registry data on district of residence; sex; dates of birth, diagnosis, and death are highly reliable, but treatment and tumour site data are less so. Lack of follow up in death certificate only registrations and failure to monitor treatments during follow up period seemed to be associated with disagreements.     

In the absence of cancer registry data, is it sensible to assess incidence using hospital separation records?

Background  

Within the health literature, a major goal is to understand distribution of service utilisation by social location. Given equivalent access, differential incidence leads to an expectation of differential service utilisation. Cancer incidence is differentially distributed with respect to socioeconomic status. However, not all jurisdictions have incidence registries, and not all registries allow linkage with utilisation records. The British Columbia Linked Health Data resource allows such linkage. Consequently, we examine whether, in the absence of registry data, first hospitalisation can act as a proxy measure for incidence, and therefore as a measure of need for service.     

Regional deprivation in Bavaria, Germany: linking a new deprivation score with registry data for lung and colorectal cancer

Objective

This study aimed to examine the differences in cancer risk by regional deprivation in Bavaria, Germany.

Methods

Multilevel Poisson regression analysis was used to evaluate the association between lung and colorectal cancer risk and community deprivation level based on data from the Cancer Registry of Bavaria (2003–2006). The communities (n?=?1,408) were classified according to the Bavarian Index of Multiple Deprivation (BIMD), differentiated into quintiles ranging from lowest to highest deprivation.

Results

Increased lung cancer risk in men and colorectal cancer risk in both genders were associated with increasing BIMD. Comparing the most deprived with the least deprived communities, the relative risk for lung cancer incidence in men was 1.39 (95% CI 1.29–1.49), for mortality risk 1.54 (95% CI 1.41–1.68). The relative risk for colorectal cancer incidence in men was 1.30 (95% CI 1.22–1.38) and in women 1.19 (95% CI 1.11–1.27); for mortality risk we found 1.57 (95% CI 1.40–1.76) in men and 1.34 (95% CI 1.19–1.51) in women.

Conclusion

Area-based deprivation is significantly associated with cancer risk in Bavaria.