Data quality in population-based cancer registration: an assessment of the Merseyside and Cheshire Cancer Registry

Validation of primary and outcome data quality in a Swedish population-based breast cancer quality registry

BACKGROUND

Population-based cancer quality registries are of great importance for the improvement of cancer care. However, little is known about the quality of recurrence data in cancer quality registries. The aim of this study was to evaluate data quality in the regional Breast Cancer Quality Registry of Central Sweden, with emphasis on the validity of recorded information on recurrence.

METHODS

Validation by re-abstraction was performed on a random sample of 800 women with primary invasive breast cancer stage I-III diagnosed between 1993 and 2010, of which 400 had at least one registered recurrence and 400 had no registered recurrence. Registry data were compared with data from medical records. Exact agreement, correlation and kappa values, sensitivity and specificity were calculated.

RESULTS

Seven hundred forty-seven women (93%) were available for analysis. Exact agreement was high for diagnostics, tumor characteristics, surgery, and adjuvant oncological treatment (90% or more for most variables). The registry's sensitivity was low for regional recurrence (47%), but higher for local and distant recurrence (80% and 75%), whereas specificity was overall high (≥ 95%). Combining all recurrence categories irrespective of localization improved sensitivity to 90% with a specificity of 91%. In 87% of women, the date of first recurrence according to medical records fell within ± 90 days of the date recorded in the registry.

CONCLUSIONS

While the quality of data in the regional Breast Cancer Quality Registry was generally high, data accuracy on recurrences was lower. The overall precision of identifying any recurrence, irrespective of localization, was high. However, the accuracy of classification of recurrences (local, regional or distant) was lower, with evidence of underreporting for each of the recurrence categories. Given the importance of recurrence-related outcomes in the assessment of quality of care, efforts should be made to improve the reporting of recurrences.

Providing a framework for evaluation disease registry and health outcomes Software: Updating the CIPROS checklist

BACKGROUND AND AIMS

Properly designed and implemented registry systems play an important role in improving health outcomes and reducing care costs, and can provide a true representation of clinical practice, disease outcomes, safety, and efficacy. Therefore, the aim of this study was to redesign and develop a checklist with items for a patient registry software system (CIPROS) Checklist.

METHOD

The study is descriptive-cross-sectional. The extraction of the data elements of the checklist was first done through a comprehensive review of the texts in PubMed, Science Direct and Scopus databases and receiving articles related to the evaluation of registry systems. Based on the extracted data, a five-point Likert scale questionnaire was created and 30 experts in this field were asked for their opinions using the two-step Delphi method.

RESULTS

A total of 100 information items were determined as a registry software evaluation checklist. This checklist included 12 groups of software architecture factors, development, interfaces and interactivity, semantics and standardization, internationality, data management, data quality and usability, data analysis, security, privacy, organizational, education and public factors.

CONCLUSION

By using the results of this research, it is possible to identify the defects and possible strengths of the registry software and put it at the disposal of the relevant officials to make a decision in this field. In this way, among the designers and developers of these softwares, the best and most appropriate ones are selected with the needs of the registry programs.

Data quality in the Swedish Quality Register of Gynecologic Cancer - a Swedish Gynecologic Cancer Group (SweGCG) study

AIM

The aim of this study is to evaluate the quality of data on endometrial (EC) and ovarian, fallopian tube, peritoneal, abdominal or pelvic cancers (OC) registered in the Swedish Quality Register of Gynecologic Cancer (SQRGC).

METHOD

A random sample of 500 patients was identified in the SQRGC and their medical charts were reviewed for re-abstraction of 31 selected core variables by an independent validator. The data in the SQRGC and the re-abstracted data were compared. The data were collected from 25 hospitals evenly distributed throughout Sweden. The main outcomes were comparability, timeliness, completeness and validity. Coverage was compared with the National Cancer Register (NCR). Timeliness was defined as the speed of registration i.e. when patients were registered in the SQRGC relative to date of diagnosis. Internationally accepted coding systems for stage, grading and histologic type were used ensuring a high degree of comparability. Correlations were estimated using Pearson's correlation coefficient and Cohen´s kappa coefficient.

RESULTS

The completeness was 95%. The timeliness was 88-91% within 12 months of diagnosis. The median degree of agreement between re-abstracted data and data in the SQRGC was 82.1%, with a median kappa value of 0.73 for ordinate variables and a median Pearson's correlation coefficient of 0.96. The agreements for the type of surgery were 76% (95% CI 70-81%; kappa 0.49) and type of primary treatment 90% (95% CI 87-94%; kappa 0.85) in OC and in EC 88% (95% CI 84-93%; kappa 0.84). The agreements for the FIGO stage were in OC and EC 74% (95% CI 68-80%; kappa 0.69) and 87% (95% CI 82-91%; kappa 0.79), respectively.

CONCLUSIONS

The data in the Swedish Quality Register for Gynecologic Cancer are of adequate quality in order to be used as a basis for research and to evaluate possible differences in treatment, lead times and treatment results.

Data Quality in Rare Diseases Registries

In the field of rare diseases, registries are considered power tool to develop clinical research, to facilitate the planning of appropriate clinical trials, to improve patient care and healthcare planning. Therefore high quality data of rare diseases registries is considered to be one of the most important element in the establishment and maintenance of a registry. Data quality can be defined as the totality of features and characteristics of data set that bear on its ability to satisfy the needs that result from the intended use of the data. In the context of registries, the 'product' is data, and quality refers to data quality, meaning that the data coming into the registry have been validated, and ready for use for analysis and research. Determining the quality of data is possible through data assessment against a number of dimensions: completeness, validity; coherence and comparability; accessibility; usefulness; timeliness; prevention of duplicate records. Many others factors may influence the quality of a registry: development of standardized Case Report Form and security/safety controls of informatics infrastructure. With the growing number of rare diseases registries being established, there is a need to develop a quality validation process to evaluate the quality of each registry. A clear description of the registry is the first step when assessing data quality or the registry evaluation system. Here we report a template as a guide for helping registry owners to describe their registry.

Estimation of Completeness of Cancer Registration for Patients Referred to Shiraz Selected Centers through a Two Source Capture Re-capture Method, 2009 Data

BACKGROUND

Cancer has important social consequences with cancer registration as the basis of moving towards prevention. The present study aimed to estimate the completeness of registration of the ten most common cancers in patients referred to selected hospitals in Shiraz, Iran by using capture-recapture method.

MATERIALS AND METHODS

This cross-sectional analytical study was performed in 2014 based on the data of 2009, on a total of 4,388 registered cancer patients. After cleaning data from two sources, using capture-recapture common findings were identified. Then, the percentage of the completeness of cancer registration was estimated using Chapman and Chao methods. Finally, the effects of demographic and treatment variables on the completeness of cancer registration were investigated.

RESULTS

The results showed that the percentages of completeness of cancer registration in the selected hospitals of Shiraz were 58.6% and 58.4%, and influenced by different variables. The age group between 40-49 years old was the highest represented and for the age group under 20 years old was the lowest for cancer registration. Breast cancer had the highest registration level and after that, thyroid and lung cancers, while colorectal cancer had the lowest registration level.

CONCLUSIONS

According to the results, the number of cancers registered was very few and it seems that factors like inadequate knowledge of some doctors, imprecise diagnosis about the types of cancer, incorrectly filled out medical documents, and lack of sufficient accuracy in recording data on the computer cause errors and defects in cancer registration. This suggests a necessity to educate and teach doctors and other medical workers about the methods of documenting information related to cancer and also conduct additional measures to improve the cancer registration system.

Bayesian estimation of a cancer population by capture-recapture with individual capture heterogeneity and small sample

BACKGROUND

Cancer incidence and prevalence estimates are necessary to inform health policy, to predict public health impact and to identify etiological factors. Registers have been used to estimate the number of cancer cases. To be reliable and useful, cancer registry data should be complete. Capture-recapture is a method for estimating the number of cases missed, originally developed in ecology to estimate the size of animal populations. Capture recapture methods in cancer epidemiology involve modelling the overlap between lists of individuals using log-linear models. These models rely on assumption of independence of sources and equal catchability between individuals, unlikely to be satisfied in cancer population as severe cases are more likely to be captured than simple cases.

METHODS

To estimate cancer population and completeness of cancer registry, we applied M(th) models that rely on parameters that influence capture as time of capture (t) and individual heterogeneity (h) and compared results to the ones obtained with classical log-linear models and sample coverage approach. For three sources collecting breast and colorectal cancer cases (Histopathological cancer registry, hospital Multidisciplinary Team Meetings, and cancer screening programmes), individual heterogeneity is suspected in cancer population due to age, gender, screening history or presence of metastases. Individual heterogeneity is hardly analysed as classical log-linear models usually pool it with between-"list" dependence. We applied Bayesian Model Averaging which can be applied with small sample without asymptotic assumption, contrary to the maximum likelihood estimate procedure.

RESULTS

Cancer population estimates were based on the results of the M(h) model, with an averaged estimate of 803 cases of breast cancer and 521 cases of colorectal cancer. In the log-linear model, estimates were of 791 cases of breast cancer and 527 cases of colorectal cancer according to the retained models (729 and 481 histological cases, respectively).

CONCLUSIONS

We applied M(th) models and Bayesian population estimation to small sample of a cancer population. Advantage of M(th) models applied to cancer datasets, is the ability to explore individual factors associated with capture heterogeneity, as equal capture probability assumption is unlikely. M(th) models and Bayesian population estimation are well-suited for capture-recapture in a heterogeneous cancer population.

Error rates in a clinical data repository: lessons from the transition to electronic data transfer--a descriptive study

OBJECTIVE

Data errors are a well-documented part of clinical datasets as is their potential to confound downstream analysis. In this study, we explore the reliability of manually transcribed data across different pathology fields in a prostate cancer database and also measure error rates attributable to the source data.

DESIGN

Descriptive study.

SETTING

Specialist urology service at a single centre in metropolitan Victoria in Australia.

PARTICIPANTS

Between 2004 and 2011, 1471 patients underwent radical prostatectomy at our institution. In a large proportion of these cases, clinicopathological variables were recorded by manual data-entry. In 2011, we obtained electronic versions of the same printed pathology reports for our cohort. The data were electronically imported in parallel to any existing manual entry record enabling direct comparison between them.

OUTCOME MEASURES

Error rates of manually entered data compared with electronically imported data across clinicopathological fields.

RESULTS

421 patients had at least 10 comparable pathology fields between the electronic import and manual records and were selected for study. 320 patients had concordant data between manually entered and electronically populated fields in a median of 12 pathology fields (range 10-13), indicating an outright accuracy in manually entered pathology data in 76% of patients. Across all fields, the error rate was 2.8%, while individual field error ranges from 0.5% to 6.4%. Fields in text formats were significantly more error-prone than those with direct measurements or involving numerical figures (p<0.001). 971 cases were available for review of error within the source data, with figures of 0.1-0.9%.

CONCLUSIONS

While the overall rate of error was low in manually entered data, individual pathology fields were variably prone to error. High-quality pathology data can be obtained for both prospective and retrospective parts of our data repository and the electronic checking of source pathology data for error is feasible.

A practical framework for data management processes and their evaluation in population-based medical registries

INTRODUCTION

We present a framework for data management processes in population-based medical registries. Existing guidelines lack the concreteness we deem necessary for them to be of practical use, especially concerning the establishment of new registries. Therefore, we propose adjustments and concretisations with regard to data quality, data privacy, data security and registry purposes.

MATERIALS AND METHODS

First, we separately elaborate on the issues to be included into the framework and present proposals for their improvements. Thereafter, we provide a framework for medical registries based on quasi-standard-operation procedures.

RESULTS

The main result is a concise and scientifically based framework that tries to be both broad and concrete. Within that framework, we distinguish between data acquisition, data storage and data presentation as sub-headings. We use the framework to categorise and evaluate the data management processes of a German cancer registry.

DISCUSSION

The standardisation of data management processes in medical registries is important to guarantee high quality of the registered data, to enhance the realisation of purposes, to increase efficiency and to enable comparisons between registries. Our framework is destined to show how one central impediment for such standardisations - lack of practicality - can be addressed on scientific grounds.

Investigating the completeness of a histopathological cancer registry: estimation by capture-recapture analysis in a French geographical unit Alpes-Maritimes, 2008

INTRODUCTION

Cancer population studies require reliable and complete baseline data, which should theoretically be available by collecting histopathology records. The completeness of such a collection was evaluated using capture-recapture analysis based on three data sources concerning breast and colorectal cancers over an identical period and within the same geographical area.

METHOD

The total number of breast and colon cancer cases was estimated using capture-recapture analysis based on the number of cases which were common or not between sources recording screened, diagnosed and treated cancers in the French Alpes Maritimes district.

RESULT

The estimated total number of new cases of breast cancer diagnosed among Alpes Maritimes residents women aged 50-75 was 791 (95% CI: 784-797) in 2008. Of these 791 cases, 729 were identified through histopathology records, thus amounting to 92.2% completeness (95% CI: 91.5-93.0%). The total estimated number of new cases of colorectal cancer diagnosed among Alpes Maritimes residents aged 50-75 was 527 (95% CI: 517-536). Of these 527 cases, 481 were identified through histopathology records, thus amounting to 91.3% completeness (95% CI: 89.7-93.0%).

CONCLUSION

The estimated completeness of cancer records collected from histopathology laboratories was higher than 90% for new cases of breast and colorectal cancer within the age range concerned by the screening programme. A verified and validated histopathology data collection may be useful for cancer population studies.

"Summary Page": a novel tool that reduces omitted data in research databases

Background

Data entry errors are common in clinical research databases. Omitted data are of particular concern because they are more common than erroneously inserted data and therefore could potentially affect research findings. However, few affordable strategies for their prevention are available.

Methods

We have conducted a prospective observational study of the effect of a novel tool called "Summary Page" on the frequency of correction of omitted data errors in a radiation oncology research database between July 2008 and March 2009. "Summary Page" was implemented as an optionally accessed screen in the database that visually integrates key fields in the record. We assessed the frequency of omitted data on the example of the Date of Relapse field. We considered the data in this field to be omitted for all records that had empty Date of Relapse field and evidence of relapse elsewhere in the record.

Results

A total of 1,156 records were updated and 200 new records were entered in the database over the study period. "Summary Page" was accessed for 44% of all updated records and for 69% of newly entered records. Frequency of correction of the omitted date of cancer relapse was six-fold higher in records for which "Summary Page" was accessed (p = 0.0003).

Conclusions

"Summary Page" was strongly associated with an increased frequency of correction of omitted data errors. Further, controlled, studies are needed to confirm this finding and elucidate its mechanism of action.

Evaluation of data quality in the cancer registry: principles and methods Part II. Completeness

The completeness of cancer registry data -- the extent to which all of the incident cancers occurring in the population are included in the registry database -- is an extremely important attribute of a cancer registry. Only a high degree of completeness in case-finding procedures will ensure cancer incidence rates and survival proportions are close to their true value. This second instalment of a two-part review of data quality methods at the cancer registry, focuses on the principles and techniques available for estimating completeness, separating methods into those that are semi-quantitative -- in that they give an indication of the degree of completeness relative to other registries or over time, and more quantitative techniques -- those that provide a numerical evaluation of the extent to which all eligible cases have been registered.

Analysis of data errors in clinical research databases

Errors in clinical research databases are common but relatively little is known about their characteristics and optimal detection and prevention strategies. We have analyzed data from several clinical research databases at a single academic medical center to assess frequency, distribution and features of data entry errors. Error rates detected by the double-entry method ranged from 2.3 to 26.9%. Errors were due to both mistakes in data entry and to misinterpretation of the information in the original documents. Error detection based on data constraint failure significantly underestimated total error rates and constraint-based alarms integrated into the database appear to prevent only a small fraction of errors. Many errors were non-random, organized in special and cognitive clusters, and some could potentially affect the interpretation of the study results. Further investigation is needed into the methods for detection and prevention of data errors in research.

Breast cancer histological classification: agreement between the Office for National Statistics and the National Health Service Breast Screening Programme

Introduction

Epidemiological studies rely on data supplied by central cancer registration sources to be timely, accurate and complete. Validation studies of such data at a national level are limited. Data collected for the Million Women Study was used to compare the level of agreement between the Office for National Statistics (ONS) and the National Health Service Breast Screening Programme (NHSBSP) in the recording of incident screen-detected breast cancer histology between 1996 and 2001.

Methods

1.3 million women aged 50 to 64 years were recruited into the Million Women Study cohort via the NHSBSP. Incident screen-detected breast cancer histologies were notified separately by the ONS and NHSBSP. ICD-10 and ICD-02 ONS codes and NHSBSP histology data were similarly coded to allow for comparison in terms of cancer invasiveness and morphology. The statistical outcome measures are percentage agreement and the kappa statistic.

Results

A total of 5,886 incident screen-detected breast cancers were available for analysis. Of the 5,886 screen-detected cancers reported by the ONS and NHSBSP, 5,684 (96.6%, κ = 0.9) agreed in terms of the degree of invasiveness. Of the 5,458 cancers that had been assigned a specific morphology code, there was exact agreement between the ONS and the NHSBSP in 4,922 cases (90.2%, κ = 0.8).

Conclusion

There is an excellent level of agreement between the ONS and NHSBSP in the recording of the histology of screen-detected breast cancer. From these results it is not possible to comment on which source of data is the more or less accurate, although the differences are very small.

Validity of a population-based cancer register in Sweden--an assessment of data reproducibility in the South-East Region Prostate Cancer Register

BACKGROUND

With a population-based setting, high coverage and accurately recorded data, the validity of a register is guaranteed. The South-East Region Prostate Cancer relies on the National Cancer Register as a basic source of data, thereby ensuring a high coverage of the corresponding geographic area. To assess the reproducibility of the data recorded a random sample of the cases were reviewed a second time and compared to the original recording.

MATERIAL AND METHODS

The South-East Region Prostate Cancer Register was started in 1987. In addition to the basic data acquired from the Swedish National Register, it also includes tumour stage, grade, treatment and, since 1992, PSA. In the first stage of quality assessment 10 cases for each of the years 1987-1996 from Linköping University Hospital were randomly selected for two independent recodings according to the same protocol as the original registration. In the second step 10 cases each for the same years from the remaining 8 hospitals in the region were selected for a single recoding.

RESULTS

No systematic deviations were seen between the two independent recodings from Linköping, a single recoding was therefore considered sufficient for assessing the reproducibility of the data from the remaining hospitals in the region. The Kappa values for agreement between the original registration and the single recoding ranged from 0.589 to 0.869.

CONCLUSION

The population-based setting and high coverage guarantees the external validity of the register. The internal validity is ensured by the high reproducibility shown in the present study.

Socioeconomic variation in colon cancer tumour factors associated with poorer prognosis

Analysis of population-based registry data (n=7393) showed that more deprived colon cancer patients had lower risk of the mucin-producing adenocarcinoma subtype, proximal subsite (to the descending colon), and no greater risk of high-grade tumours. Tumour factors therefore appear unlikely to account for socioeconomic gradients in survival.

Defining and improving data quality in medical registries: a literature review, case study, and generic framework

Over the past years the number of medical registries has increased sharply. Their value strongly depends on the quality of the data contained in the registry. To optimize data quality, special procedures have to be followed. A literature review and a case study of data quality formed the basis for the development of a framework of procedures for data quality assurance in medical registries. Procedures in the framework have been divided into procedures for the co-ordinating center of the registry (central) and procedures for the centers where the data are collected (local). These central and local procedures are further subdivided into (a) the prevention of insufficient data quality, (b) the detection of imperfect data and their causes, and (c) actions to be taken / corrections. The framework can be used to set up a new registry or to identify procedures in existing registries that need adjustment to improve data quality.

Location of death in Canada. A comparison of 20th-century hospital and nonhospital locations of death and corresponding population trends

This report compares 20th-century Canadian hospital and nonhospital location-of-death trends and corresponding population mortality trends. One of the chief findings is a hospitalization-of-death trend, with deaths in hospital peaking in 1994 at 80.5% of all deaths. The rise in hospitalization was more pronounced in the years prior to the development of a national health care program (1966). Another key finding is a gradual reduction since 1994 in hospital deaths, with this reduction occurring across all sociodemographic variables. This suggests nonhospital care options are needed to support what may be an ongoing shift away from hospitalized death and dying.

An application of the two-source capture-recapture method to estimate the completeness of the Tuscany Cancer Registry, Italy

The purpose of this study was to apply a two-way capture-recapture method to estimate the Tuscany Cancer Registry completeness, taking into account the presence of dependence between sources. Cases incident during 1995-1996 were flagged according to three sources of information: clinical notes, pathological reports and death certificates. For each group of cases notified by one source the dependence between the other two has been quantified and the completeness has been estimated by a two-way capture-recapture method. When only two (or substantially two) sources are dependent on each other it is possible to correct for it by pooling the two sources in a single group and comparing it with the remainder source by a two-way capture-recapture method. The capture-recapture method has been applied to the overall 12 387 incident cases and to 1569 female breast and 1443 lung cancer cases. After correction for the greatest dependence among the three couples of sources of information, the estimates of completeness were 97.4% for the whole case series, 88.7% for female breast and 99.6% for lung cancer. With the limit of multiple strong dependence between sources, the two-way capture-recapture method seems a simple and useful tool for estimating the completeness of cancer registration.

Concordance on the recording of cancer in the Saskatchewan Cancer Agency Registry, hospital charts and death registrations

Accurate and complete registries are an important source of knowledge about cancer. The concordance of the recording of neoplasms in the Saskatchewan cancer registry with that in hospital charts and death registrations was evaluated for 368 patients. The agreement between registry and hospital charts or death registrations was excellent (kappa: 0.93; 95% confidence interval: 0.89, 0.97), with 91.3% of those with cancer having the same neoplasm recorded in their chart or death registration as in the registry. There was only one patient whose hospital chart indicated cancer who was not in the registry and one apparent major discrepancy relating to the cancer site, which was due to the recording of the primary site in the registry and a secondary in the hospital chart. Although based on a relatively small number of patients, these results suggest a high degree of consistency between cancer registry, hospital charts and death registrations in Saskatchewan.

Colorectal cancer registration: the central importance of pathology

BACKGROUND

Changes in cancer care have increased the importance of cancer registries in monitoring trends and outcomes. Registries are increasingly using computerised systems, such as patient administration and histopathology, as data sources. Omissions by registries can cause interpretation errors, but use of multiple data sources can overcome this.

METHODS

Registrations of new colorectal cancers in Cornwall were compared with cases identified from primary sources over one year.

RESULTS

Two hundred and thirty cases were identified locally, 93% in documentary records, 89.6% via histopathology, and 81.3% in the clinical data capture module of the patient administration system. Two hundred and forty four cases were known to the regional registry, but after eliminating wrongly assigned and unconfirmed cases only 201 remained. Twenty nine cases identified locally, particularly cases of advanced disease, were unknown to the registry.

CONCLUSIONS

District registers based on histopathology augmented from other sources would provide more accurate and less biased information than existing regionally based methods.