Data quality at the Cancer Registry of Norway: An overview of comparability,completeness, validity and timeliness

AimTo provide a comprehensive evaluation of the quality of the data collected on both solid and non-solid tumours at the Cancer Registry of Norway (CRN).MethodsEstablished quantitative and semi-quantitative methods were used to assess comparability, completeness, accuracy and timeliness of data for the period 1953–2005, with special attention to the registration period 2001–2005.ResultsThe CRN coding and classification system by and large follows international standards, with some further subdivisions of morphology groupings performed in-house. The overall completeness was estimated at 98.8% for the registration period 2001–2005. There remains a variable degree of under-reporting particularly for haematological malignancies (C90–95) and tumours of the central nervous system (C70–72). For the same period, 93.8% of the cases were morphologically verified (site-specific range: 60.0–99.8%). The under-reporting in 2005 due to timely publication is estimated at 2.2% overall, based on the number of cases received at the registry during the following year.ConclusionThis review suggests the routines in place at the CRN yields comparable data that can be considered reasonably accurate, close-to-complete and timely, thereby justifying our policy of the reporting of annual incidence one year after the year of diagnosis.     

Evaluation of data quality in the cancer registry: Principles and methods. Part I: Comparability,validity and timeliness

The value of the modern cancer registry and its ability to carry out cancer control activities rely heavily on the underlying quality of its data and the quality control procedures in place. This two-part review provides an update of the practical aspects and techniques for addressing data quality at the cancer registry. This first installment of the review examines the factors influencing three of the four key aspects, namely, the comparability, validity and timeliness of cancer registry data. Comparability of cancer data may be established through a comprehensive review of the registration routines in place. Validity is examined via numerical indices of that permit comparisons with other registries, or, within a registry, over time, or with respect to specified subsets of cases. There are no international guidelines for timeliness at present, although specific standards for the abstraction and reporting of registry have been set out by certain organisations.     

Comparability of cancer identification among Death Registry, Cancer Registry and Hospital Discharge Registry

Registry-based cancer incidence and mortality data are widely used for etiologic research, cancer control and health care monitoring and planning. The complete coverage of all cases is the key criteria of data quality but it is difficult to assess because the alternative sources of data may be flawed. The aim of our study was to examine, at a nationwide level, the completeness of the Swedish Cancer Registry (CR) regarding persons who died of cancer, based on the Cause of Death Registry (DR), and using the Hospital Discharge Registry (HDR) as an additional source of data. Individuals who died of cancer from years 1999 through 2008 recorded in DR were linked to CR and HDR. A total of 190,692 individuals were identified from DR with cancer as the underlying cause of death; the mean identification rate of concordant cancer in CR was 79.8%, depending on tumor site and age at death. Breast, bladder and prostate cancers showed the highest rate of identification, whereas bone, liver and pancreatic cancers showed the lowest rate of identification. CR had no records on 10.6% of cancer cases recorded in DR. Similarly, the identification rate in HDR was 84.5% for concordant cancer and with 9.6% of cases missing. Neither source reported cancers for 3.4% of cancer cases recorded in DR. In conclusion, some 10% of cancer deaths had no cancer records in CR or in HDR, and 3.4% were missing in both sources. The identification rate depended on tumor site, age at death and, to some extent, death outside hospital.     

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

Merseyside and Cheshire Cancer Registry (MCCR) data quality was assessed by applying literature-based measures to 27,942 cases diagnosed in 1990 and 1991. Registrations after death (n = 8535) were also audited (n = 917) to estimate death certificate only (DCO) case accuracy and the proportion of registrations notified by death certificate (DC). Ascertainment appeared to be high from the registration/mortality ratio for lung [1.01:1] and to be low from capture-recapture estimates (59.4%), varying significantly with site from oesophagus [92.2% (95% CI 88.5-95.9)] to breast [47.5 (95% CI 41.8-53.2)]. The estimated DC-dependent proportion was 20% (5601 out of 27 942) with successful traceback in 3533 out of 5601 (63.1%) cases. DCO flagging (2497 out of 27,942, 8.9%) overestimated true DCO cases (2068 out of 27,942, 7.4%). The proportion of cases of unknown primary site was low (1.5%), varying significantly with age [0-4.2%, (95% CI 2.5-5.9)] and district [0.8% (95% CI 0.3-1.3) to 2.2% (95% CI 1.8-2.6)]. The median diagnosis to registration interval appeared to be good (10 weeks), varying significantly with site (P < 0.0001), age (P < 0.0001) and district (P < 0.0001). The proportion with a verified diagnosis was 77.3%, varying significantly with site [lung 55.2% (95% CI 53.7-56.7) to cervix 96.9% (95% CI 96.3-97.5)], age [45.2% (95% CI 40.9-49.5) to 97.5% (95% CI 96.4-98.6)] and district [71.8% (95% CI 69.9-73.8) to 82.5% (95% CI 80.7-84.3)]. The DCO percentages varied similarly by site [non-melanoma skin 0.4% (95% CI 0.2-0.6) to lung 22.6% CI (95% 19.9-25.3)], age [0.7(95% CI 0.1-1.4) to 23.0 (95% CI 19.4-26.6)] and district [6.9% (95% CI 5.7-8.1) to 13.9% (95% CI 12.9-15.0)]. MCCR data quality varied with age, site and district - inviting action - and apparently compares favourably with elsewhere, although deficiencies in published data hampered definitive assessment. Putting quality assurance into practice identified shortcomings in the scope, definition and application of existing measures, and absent standards impeded interpretation. Cancer registry quality assurance should henceforward be within an explicit framework of agreed and standardized measures.     

Survey of Potential Cancer Registry Items to Enhance the Usefulness of Cancer Registry Data

Background: Cancer registry data can help plan for cancer services and to identify where further progress is needed, in order to improve the lives of patients with cancer. This study investigated the possibility of collecting additional information and the priority of the information by examining other cancer registry items. We aimed to suggest additional data items to be collected to enhance the usefulness of cancer registry data. Methods: We examined items that could potentially be added by comparing the cancer registration items in five foreign registries and large hospitals in Korea. Based on the foreign and domestic hospital cancer registry data, a questionnaire survey was administered to 272 cancer registry workers nationwide and 10 cancer experts to investigate the possibility of expanding the variables. The proportion and rank of each item were analyzed. Results: There were similar items for demographic information and cancer diagnosis between foreign cancer registries and the Korea Central Cancer Registry (KCCR). However, the KCCR had fewer items for staging, treatment, and follow-up. There were 29 items to be collected with high priority. Items under demographic information included date of birth, race and country of birth. Items for cancer diagnosis included type of cancer, smoking history and type of pathologic test. Treatment information included the date of treatment, chemotherapy and radiation. Items under the stage and prognostic factors included TNM stage, collaborative stage, and comorbidities. Finally, items under follow-up information included survival, cancer state and recurrence information. Conclusions: Cancer registration workers and cancer experts generally agreed on the need to expand the essential items for cancer registration. The findings of this study will be useful for devising plans to expand cancer registration items.     

Cancer Incidence in Saudi Arabia: 2012 Data from the Saudi Cancer Registry

Background: In order to most appropriately allocate healthcare and research funding for cancer, it is important to have accurate population-based incidence data. The Saudi Cancer Registry (SCR) provides such information, covering the time period from 1994 to the present day. The current report concerns an overview of cancer incidence statistics for Saudi Arabia in 2012. Methods: The SCR collects data from healthcare facilities throughout the Kingdom of Saudi Arabia. All newly diagnosed cases of cancer are recorded, with information on site and histology. For the present report, age-standardised and age-specific incidence rates (ASR, AIR, respectively) were calculated, with attention to gender-specific and regional differences. Results: The total number of incident cases of cancer identified by the SCR in 2012 was 14,336, with 6,791 (47.5%) among males and 7,545 (52.6%) among females. Of this total, 11,034 cases (76.9%) occurred in patients of Saudi origin. For Saudi males, the overall ASR (inc. all cancer sites) was 78.1 per 100,000 people, while that for females was 86.7. Incidence varied by region, with the Eastern region and Riyadh displaying the highest ASRs for both males and females, and Hail and Jazan displaying the lowest. Incidence varied by gender, with colorectal cancer (13.3%), non-Hodgkin lymphoma (NHL; 8.4%), and leukaemia (8.2%) being the most common types in males, and breast (25.8%), thyroid (11.7%), and colorectal cancers (9.3%) being the most common in females. Conclusions: This analysis of cancer incidence in Saudi Arabia demonstrated significant differences according to gender, age, and region of the Kingdom. The data should help ensure the most appropriate allocation of resources, with the aim of minimising the healthcare burden associated with cancer.     

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.     

西藏拉萨市肿瘤登记资料初步分析

[目的]探讨西藏拉萨市恶性肿瘤的分布特征.[方法]对托萨市肿瘤登记处收集的恶性肿瘤病例资料进行整理和统计分析.[结果]2001～2005年,拉萨市8家医疗单位共报告了两藏自治区新发生的恶性肿瘤病例1 097例(男性723例,女性374例),主要包括消化器官肿瘤(64.7%)、呼吸和胸腔内器官肿瘤(6.8%)、女性生殖器官肿瘤(6.7%)和女性乳房肿瘤(5.9%).在拉萨市肿瘤登记地区2005年的病例中,经组织病理学诊断的比例为87.7%,影像或生化检测的比例为5.0%,不详者6.7%.男性常见的恶性肿瘤足肝癌、胃癌和肺癌,合计占男性病例74.4%:女性为肝癌、乳腺癌、胃癌、宫颈癌、食管癌和卵巢癌,合计占女性病例78.8%.与30年前相比,目前拉萨市男性肝癌、肺癌和女性乳腺癌、宫颈癌、卵巢癌的比例有上升的趋势.[结论]随着人口增长与社会发展,拉萨市恶性肿瘤病例的分布也发生变化.今后应加强西藏地区肿瘤防治基础建设,继续深入开展肿瘤登记和及时掌握癌症发病情况,积极进行重点肿癌的防治研究.     

Cancer Incidence and Mortality: District Cancer Registry,Trivandrum, South India

Background: Cancer is emerging as a major cause of morbidity and mortality in low and middle-income countries. Cancer registry figures help for planning and delivery of health services. This paper provided the first results of cancer incidence and mortality [Crude (CR) and age-standardized (ASR)] rates (world-standard population) of Trivandrum district, South India and compared with other registries under the network of National Cancer Registry Programme (NCRP), Government of India. Materials and Methods: Trivandrum district cancer registry encompasses a population of 3.3 million, compiles data from nearly 75 sources (hospitals and diagnostic laboratories) and included under the NCRP in 2012. During 2012-2014, registry recorded 15,649 incident cases and 5667 deaths. Proportion of microscopic diagnosis was 85% and ‘Death certificate only’ was 8%. Results: Total cancer incidence (CRs) rates were 161 and 154 (ASR: 142.2 and 126) and mortality rates were 66 and 49 (ASR: 54 and 37) per 105 males and females respectively. Common cancers in males were lung (ASR:19), oral cavity (ASR:15), colo-rectum (ASR:11.2), prostate (ASR:10.2) and lymphoma (ASR:7) and in females, breast (ASR:36), thyroid (ASR:13.4), cervix-uteri (ASR:7.3), ovary (ASR:7) and colo-rectum (ASR:7). Nationally, the highest CRs for breast, prostate, colo-rectum, corpus-uteri and urinary bladder cancers and low incidence of cervix-uteri cancer were observed in Trivandrum. Conclusion: Cancer incidence (CR) in Trivandrum was the highest in both genders in India (except Aizwal). This is mainly due to the highest life-expectancy in Kerala. Also, an epidemiologic transition in cancer pattern is taking place and is changing to more similar to "western" jurisdictions.     

Cancer Prevalence in Aichi,Japan for 2012: Estimates Based on Incidence and Survival Data from Population-Based Cancer Registry

Background: Cancer is the leading cause of death among both men and women in Japan. Monitoring cancer prevalence is important because prevalence data play a critical role in the development and implementation of health policy. We estimated cancer prevalence in 2012 based on cancer incidence and 5-year survival rate in Aichi Prefecture using data from a population-based cancer registry, the Aichi Cancer Registry, which covers 7.4 million people. Methods: The annual number of incident cases between 2008 and 2012 was used. Survival data of patients diagnosed in 2006–2008 and followed up until the end of 2012 were selected for survival analysis. Cancer prevalence was estimated from incidence and year-specific survival probabilities. Cancer prevalence was stratified by sex, cancer site (25 major cancers), and age group at diagnosis. Results: The estimated prevalence for all cancers in 2012 was 68,013 cases among men, 52,490 cases among women, with 120,503 cases for both sexes. Colorectal cancer was the most incident cancer with 6,654 cases, accounting for 16.0% of overall incident cases, followed by stomach cancer with 5,749 cases (13.8%) and lung cancer with 5,593 cases (13.4%). Prostate cancer was the most prevalent among men, accounting for 21.5%, followed by colorectal and stomach cancers. Breast cancer was the most prevalent among women, accounting for 28.6%, followed by colorectal, stomach, and uterine cancers. Conclusion: This study provides cancer prevalence data that could serve as useful essential information for local governments in cancer management, to carry out more practical and reasonable countermeasures for cancer.     

阳城县肿瘤登记资料质量评价

[目的]应用肿瘤登记资料质量控制指标,对阳城县肿瘤登记资料的可比性、有效性和完整性进行分析与评价。[方法]对阳城县肿瘤登记处提交《五大洲癌症发病率》（第Ⅹ卷）中的2003～2007年的数据资料中MV%、DCO%、M/I、逐年发病率变化趋势的稳定性等质控指标进行统计分析。[结果]阳城县2003～2007年共报告恶性肿瘤新发病例6 339例,男女性别比为1.29∶1;死亡4 210例,男女性别比1.42∶1。病理诊断比例（MV%）为86.05%;只有死亡医学证明书比例（DCO%）为0.47%;同期恶性肿瘤死亡/发病之比（M/I）为0.66。[结论]应进一步规范和完善肿瘤登记报告系统,重点是提高乡村一级报告人员的工作责任心和业务素质,从源头上减少漏报,并加强部门、区域间的协作交流,从整体上全面提高阳城县肿瘤登记报告工作质量。     

Gastric Cancer in Ardabil,Iran - a Review and Update onCancer Registry Data

The incidence rate of gastric cancer in western countries has shown a remarkable decline in recent yearswhile it is still the most common cancer among men in Iran. Ardabil, a North Western province, was found tohave the highest rate of GC in Iran and one of the highest gastric cardia cancer rates in the world. We used themost recent data from Ardabil cancer registry to update on the incidence and mortality of GC and performedan extensive search of the English and Persian literature in Pub Med, Embase and all 5 Persian web-baseddatabases, respectively, to summarize all possible risk factors for GC in Ardabil. The age-standardized incidencerate of gastric cancer was 51.8 (95% CI: 47.8-55.8) in men and 24.9 (95% CI: 21.5-27.2) in women per 100,000.Age-standardized mortality rates for gastric cancer in this population were 32.2 (95% CI: 29.1-35.3) and 16.3(95% CI: 13.9-18.6). The gastric cardia sub-site was the most common location (32.7%) in Ardabil. Accordingto our review H.pylori infection, gastroesphageal reflux symptoms, tobacco smoking, and high intakes of salt,red meat and dairy products increase the risk of GC while diets with a high content of allium vegetables andfruits, especially citrus fruits, and consumption of fresh fish, were significantly protective against GC. Weconclude that Ardabil has the highest rate of GC in Iran and one the highest rates of gastric cardia cancer inthe world, with no evidence of decline in incidence since 2000. In addition to H.pylori infection, the epidemicof gastroesphageal reflux disease and several dietary factors may be responsible for the very high incidence ofgastric cardia cancer in Ardabil.     

Evaluation of data quality in the Spanish EURECCA Esophagogastric Cancer Registry

BackgroundAlthough the number of nationwide clinical registries in upper gastrointestinal cancer is increasing, few of them perform regular clinical audits. The Spanish EURECCA Esophagogastric Cancer Registry (SEEGCR) was launched in 2013. The aim of this study was to assess the reliability of the data in terms of completeness and accuracy.MethodsPatients who were registered (2014–2017) in the online SEEGCR and underwent esophagectomy or gastrectomy with curative intent were selected for auditing. Independent teams of surgeons visited each center between July 2018 and December 2019 and checked the reliability of data entered into the registry. Completeness was established by comparing the cases reported in the registry with those provided by the Medical Documentation Service of each center. Twenty percent of randomly selected cases per hospital were checked during on-site visits for testing the accuracy of data (27 items per patient file). Correlation between the quality of the data and the hospital volume was also assessed.ResultsSome 1839 patients from 19 centers were included in the registry. The mean completeness rate in the whole series was 97.8% (range 82.8–100%). For the accuracy, 462 (25.1%) cases were checked. Out of 12,312 items, 10,905 were available for verification, resulting in a perfect agreement of 95% (87.1–98.7%). There were 509 (4.7%) incorrect and 35 (0.3%) missing entries. No correlation between hospital volume and the rate of completeness and accuracy was observed.ConclusionsOur results indicate that the SEEGCR contains reliable data.     

Finding Incident Breast Cancer Cases through US Claims Data and a State Cancer Registry

Objective: With the increasing availability of automated health-care data, new methods are available to screen large populations for the presence of cancer diagnoses. However, it is crucial to evaluate how completely incident cancer cases can be ascertained using these data sources. Methods: We used capture–recapture techniques to estimate the total number of incident breast cancer cases occurring within one state during a 3-year period. We then compared the ascertainment of these cases by the following two data sources: claims for breast cancer surgery recorded in Medicaid and Medicare data vs a cancer registry in the same state. Results: Medicaid–Medicare breast cancer surgery claims identified 68% of the total estimated number of incident breast cancer cases while cancer registry data identified 78%. Case ascertainment improved markedly to 91% when both registry and Medicare–Medicaid data sources were used together. The sensitivity of ascertainment was lower for Medicaid–Medicare data among those aged under 65 and non-white; ascertainment was lower for the registry among women who were aged under 65, poor, and non-white. Conclusions: Combining health insurance claims data with a population-based cancer registry improved the identification of incident cases of breast cancer, and may be particularly useful among demographic groups found to be at highest risk of under-ascertainment such as younger women, the poor, and racial minorities.     

Data Quality and Quality Control of a Population-Based Cancer Registry: Experience in Finland

Cancer registries should pay great attention to the quality of their data, both in terms of completeness (all cancer patients in the population are registered) and accuracy (data on individual cancer patients must be correct). In addition to technical measures in the data processing, different types of checks and comparisons should be routine practice. Active research policy and ambitious, research-oriented staff with competence in medicine, biostatistics and computer science are essential in terms of maintaining good data quality.     

基层肿瘤登记报告存在问题及对策探讨

目前我国肿瘤登记处中县级和县级市占一半以上,基层肿瘤防治专业队伍薄弱,肿瘤漏报现象较为严重．病理资料收集较难,登记数据利用率不高。全文结合中国肿瘤登记年报数据,分析当前基层肿瘤登记处存在的问题,并探讨其对策。