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PURPOSE: People with intellectual and developmental disabilities (IDD) experience high rates of depression. Evidence indicates that physical activity, or participation in a sports club, in a supportive social environment has mental and physical health benefits. Adults with IDD, on average, engage in low levels of physical activity. The purpose of this study was to compare the rates of depression among young adult Special Olympics participants with IDD compared to non-participants with IDD. METHODS: This was a 20-year retrospective cohort study of young adults (19-29 years) with IDD in the province of Ontario, Canada that compared rates of depression among Special Olympics participants (n = 8710) to non-participants (n = 42,393) using administrative health databases housed at ICES (formerly the Institute for Clinical Evaluative Sciences). Using cox proportional hazard models, the crude hazard ratios were calculated for the association between each independent variable and the dependent variable. RESULTS: After controlling for other variables, the hazard rate for depression among Special Olympics participants compared to the hazard rate for depression among non-participants generated an adjusted hazard ratio of 0.51. Over the 20-year follow-up, the participants were 0.51 times as likely to develop depression as non-participants; this represents a 49% reduction in risk among Special Olympics participants. This result was statistically significant and represents a medium effect size. CONCLUSION: Future research is needed on how much of this risk reduction is related to a physiological response to physical activity/exercise, and how much is related to the social connectedness of being part of a group participating in Special Olympics.
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Deficiências do Desenvolvimento , Deficiência Intelectual , Criança , Humanos , Adulto Jovem , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/epidemiologia , Estudos Retrospectivos , Depressão/diagnóstico , Depressão/epidemiologia , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/epidemiologia , Ontário/epidemiologiaRESUMO
PURPOSE: To validate three approaches for identifying incident cases of pancreatic cancer in Ontario administrative claims data. METHODS: We created a cohort using Ontario (Canada) administrative health data from 2002 to 2012 and identified cases of pancreatic cancer with three approaches, using the Ontario Cancer Registry (OCR) as the reference standard. In the any diagnosis approach, cases were defined by primary or secondary diagnostic codes for pancreatic cancer in outpatient or inpatient records. In the any inpatient diagnosis approach, cases were defined using only diagnoses in hospital discharge abstracts. In the algorithm approach, cases were identified by an algorithm that combined the first two approaches. Comparing each approach to the OCR, we calculated the expected value and 95% confidence interval (CI) of the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). We also compared the event dates using each approach with those recorded in the OCR. RESULTS: Among a total of 12 060 837 patients in Ontario administrative health data sources, 13 999 incident pancreatic cancer cases were identified in the OCR. Sensitivity ranged from 72.5% (algorithm) to 97.5% (any diagnosis), and PPV ranged from 38.4% (any diagnosis) to 78.9% (any inpatient diagnosis). Specificity and NPV were ~100% for all approaches. The median absolute difference in cancer event date ranged 0 to 15 days. The any inpatient diagnosis method had the highest PPV (78.9%; 95% CI: 78.2-79.5%) and moderate sensitivity (86.6%; 95% CI: 86.0-87.2%). CONCLUSION: Inpatient diagnoses of pancreatic cancer in Ontario administrative heath data are suitable for pancreatic cancer case identification.
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Algoritmos , Bases de Dados Factuais , Neoplasias Pancreáticas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Ontário/epidemiologia , Neoplasias Pancreáticas/etiologia , Reprodutibilidade dos Testes , Adulto JovemRESUMO
PURPOSE: The Canadian Network for Observational Drug Effect Studies (CNODES) is a network of Canadian research centres using administrative data to conduct distributed drug safety and effectiveness studies. In this study, we compare the provincial administrative databases and illustrate the potential impact of database differences on a CNODES study about domperidone and the risk of ventricular tachyarrhythmia and sudden cardiac death (VT/SCD). METHODS: We assessed the impact of varying versions and precision of the International Classification of Diseases coding system in physician claims data, and the content and completeness of hospital discharge abstracts across CNODES sites, as these variations can introduce differences in the study cohorts formed and affect study results. RESULTS: In our study of 214 962 patients, hospital diagnosis type (such as most responsible, admitting, or secondary diagnosis) was missing in some provinces, resulting in misclassification of the outcome and variation in rates and risk estimates. Incidence rates of VT/SCD ranged from 19.8 (95% confidence interval [CI] 17.7-22.2) per 10 000 person-years in British Columbia to 53.4 (95% CI 50.3-56.5) in Quebec. While most provinces reported an increased risk of VT/SCD, a null effect was observed in Quebec (rate ratio 1.06; 95% CI 0.79-1.41). CONCLUSIONS: Distributed analyses allow for rapid responses to drug safety signals. However, variation in characteristics of the administrative data across research centres can influence study results. By identifying the sources of database heterogeneity, one can evaluate the potential biases these differences may introduce, highlighting the importance of considering such variation in distributed networks.
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Antieméticos/efeitos adversos , Bases de Dados Factuais , Morte Súbita Cardíaca/epidemiologia , Domperidona/efeitos adversos , Classificação Internacional de Doenças , Farmacovigilância , Canadá/epidemiologia , Morte Súbita Cardíaca/etiologia , Humanos , Incidência , Avaliação de Programas e Projetos de SaúdeRESUMO
PURPOSE: Recent studies from national registries have described changing patterns in epidemiology of acromegaly. Our retrospective study used administrative databases to estimate prevalence and incidence of acromegaly in the Piedmont Region, Italy. METHODS: This study was conducted in Piedmont between 2012 and 2016 on administrative health databases for inpatients and outpatients of any age. Enrollees were included if claims suggestive of acromegaly were identified in at least two of the following databases: Drug Claims Registry, Hospital Information System, Co-payment Exemption Registry and Outpatient Specialist Service Information System. RESULTS: 369 individuals (M = 146, F = 223) met our criteria. Overall incidence was 5.3 per million person years (95% CI 4.2-6.7), and prevalence was 83 cases per million inhabitants (95% CI 75-92). Mean age was 50.9 years. Both incidence and prevalence were slightly higher among women (rate ratio 1.08, prevalence ratio 1.43). Age-specific incidence was similar between sexes up to 39 years and diverged thereafter, with an increasing trend recorded among men. Prevalence was higher in women aged 40-79 years, and increased continuously up to 79 years in both sexes. CONCLUSIONS: This is the first population-based study conducted in Italy to estimate incidence and prevalence of acromegaly and results show a higher prevalence than previously reported. Although our algorithm requires proper validation, it constitutes a promising tool to describe the epidemiology of acromegaly.
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Acromegalia/epidemiologia , Bases de Dados Factuais , Sistema de Registros/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Incidência , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Estudos Retrospectivos , Adulto JovemRESUMO
PURPOSE: There is a lack of real-world studies evaluating the impact on survival of an evidence-based pathway of care in breast cancer. The aim of this work is to investigate the effect of adherence to guidelines on long-term survival for a cohort of Italian breast cancer patients. METHODS: The cohort included incident female breast cancer cases (2007-12), from the registry of the Milan province (Italy), not metastatic at diagnosis and receiving primary surgery. We selected sets of indicators, according to patient and tumor characteristics. We then defined the pathway of care as adherent to guidelines if it fulfilled at least 80% of the indicators. Indicators were measured using different administrative health databases linked on a unique key. A causal inference approach was used, drawing a directed acyclic graph and fitting an inverse probability weighted marginal structural model, accounting for patient's demographic, socioeconomic and tumor characteristics. RESULTS: The analysis included 6333 patients, 69% of them were classified as having an adherent care. Mean age was 61 years (standard deviation, 13.6 years) and half of the patients were in Stage I (50%) at diagnosis. Median follow-up time was 5.6 years. Overall, 5-year survival was 90% (95% CI, 89-91%). The estimated risk of death was 30% lower for patients with adherent than nonadherent care (hazard ratio [HR], 0.66; 95% CI, 0.55-0.77). CONCLUSIONS: Our study confirms, in real-world care, the impact on survival of receiving a care pathway adherent to guidelines in non-metastatic breast cancer patients.
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Neoplasias da Mama/epidemiologia , Neoplasias da Mama/terapia , Fidelidade a Diretrizes , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Feminino , Guias como Assunto , Humanos , Itália , Mamografia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Sistema de RegistrosRESUMO
BACKGROUND: A narrow time window in infancy may be relevant for the aetiology of immune-mediated type 1 diabetes. We investigated whether a non-specific immune stimulation in the first year of life, as resulting from Bacillus Calmette-Guérin (BCG) vaccination, was associated with childhood diabetes. METHODS: Using data from a birth cohort assembled through linkage of administrative databases, 78,492 subjects born in 1974 were the object of the present analysis. Information was extracted from the birth, death, and BCG vaccination registries. Diabetes-related health services were obtained from administrative health databases (physician billing claims and hospitalisation data) until 1994. Subjects were classified as having diabetes according to two validated definitions: (1) ≥2 diabetes-related medical visits within 2 years or ≥1 hospitalisation for diabetes; and 2) ≥4 diabetes-related medical visits within 2 years. Cox proportional hazards regression was used to estimate adjusted hazard ratios (HR) and 95% confidence interval (CI), adjusted for potential confounders. RESULTS: Forty-four per cent of subjects were BCG vaccinated in the first year of life. According to the first and second definition, respectively, 293 (0.37%) and 230 (0.29%) subjects were classified as having diabetes. There was no association between BCG vaccination in the first year of life and risk of diabetes with either definition (HR(def1) = 0.92, 95% CI 0.73, 1.17; HR(def2) = 1.04, 95% CI 0.80, 1.37), and results did not differ by sex. CONCLUSIONS: Given the potentially critical importance of the exposure window and paucity of studies addressing BCG vaccination timing in relation to diabetes risk, this question deserves further investigation.
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Vacina BCG , Diabetes Mellitus Tipo 1/epidemiologia , Vacinação/estatística & dados numéricos , Criança , Estudos de Coortes , Humanos , Lactente , Idade Materna , Idade Paterna , Quebeque/epidemiologia , Fatores de RiscoRESUMO
BACKGROUND: Current recommendations for managing persistent asthma during pregnancy when low-dose inhaled corticosteroids (ICSs) are insufficient include adding a long-acting ß2-agonist (LABA) or increasing the ICS dose. However, there are no data to help clinicians evaluate the safest regimen during pregnancy. OBJECTIVE: We sought to compare the risk of major congenital malformations in asthmatic women exposed to a LABA plus ICS combination and those exposed to ICS monotherapy at higher doses during the first trimester. METHODS: A cohort of asthmatic pregnant women exposed to ICSs during the first trimester who delivered between January 1990 and March 2009 was established. The primary outcome was major malformation recorded at birth or during the first year of life. Two subcohorts were established as follows: (1) users of a LABA plus low-dose ICS combination or users of a medium-dose ICS and (2) users of a LABA plus medium-dose ICS combination or users of a high-dose ICS. Generalized estimating equations were used to compare the risk of major malformations between the groups. RESULTS: In one subcohort there were 643 women who used a LABA plus low-dose ICS and 305 who used a medium-dose ICS; the other subcohort included 198 users of a LABA plus medium-dose ICS and 156 users of a high-dose ICS. The prevalence of major malformations was 6.9% and 7.2%, respectively. The adjusted odds ratio for major malformations was 1.1 (95% CI, 0.6-1.9) when a LABA plus low-dose ICS was used compared with a medium-dose ICS and 1.2 (95% CI, 0.5-2.7) when a LABA plus medium-dose ICS was used compared with a high-dose ICS. CONCLUSION: The risk of major malformations was similar with a LABA plus ICS combination and ICS monotherapy at higher doses, suggesting that both therapeutic options can be considered during pregnancy.
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Corticosteroides/administração & dosagem , Agonistas Adrenérgicos beta/administração & dosagem , Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Asma/epidemiologia , Anormalidades Congênitas/epidemiologia , Administração por Inalação , Adolescente , Adulto , Quimioterapia Combinada , Feminino , Humanos , Recém-Nascido , Masculino , Razão de Chances , Gravidez , Primeiro Trimestre da Gravidez , Prevalência , Quebeque/epidemiologia , Estudos Retrospectivos , Risco , Adulto JovemRESUMO
Background: The treatment of rheumatoid arthritis (RA), a chronic systemic inflammatory autoimmune disease, is based on disease-modifying anti-rheumatic drugs (DMARDs). Typically, it starts with conventional synthetic DMARDs (csDMARDs), and depending on the patient's response to the treatment and the adverse events experienced, biological DMARDs (bDMARDs) are initiated. bDMARDs are more specific to inflammatory factors than csDMARDs and more efficient in inducing remission and low disease activity. Thus, this study aimed to assess the effectiveness of biological therapy in patients with rheumatoid arthritis in administrative health databases. Methods: PubMed, Embase, Lilacs, Ovid, Scopus, and Web of Science databases were searched from inception to 21 October 2021, to identify observational studies that evaluated the effectiveness of biological therapy in patients with rheumatoid arthritis using administrative databases and real-world data. The methodological quality was assessed by the methodological index for non-randomized studies (MINORS). A fixed or random-effects model estimated risk ratios with 95% confidence intervals. The analysis was divided into four groups: tumor necrosis factor inhibitors (TNFi) versus non-TNFi; TNFi versus TNFi (adalimumab, etanercept, and golimumab versus infliximab); bDMARDs versus Janus kinase inhibitors (JAKi); and bDMARDs monotherapy versus combination therapy (bDMARDs and MTX). Results: Twenty-one records were eligible for inclusion in this systematic review and meta-analysis; seven population-based cohorts, eight prospective, and six retrospective cohort studies. Overall, 182,098 rheumatoid arthritis patients were evaluated. In the meta-analysis, lower effectiveness was observed among TNFi users than in non-TNFi (RR: 0.88; 95% CI: 0.81-0.95; p < 0.01; I2 = 94.0%) and bDMARDs than in JAKi (RR: 0.86; 95% CI: 0.79-0.94; p < 0.01; I2 = 93.0%). Higher effectiveness among adalimumab, etanercept, and golimumab than in infliximab (RR: 1.19; 95% CI: 1.05-1.36; p < 0.01; I2 = 96.0%) was found. No significant differences in the effectiveness of bDMARD monotherapy compared to combination therapy (RR: 0.83; 95% CI: 0.68-1.00; p < 0.01; I2 = 81.0%) was observed. E-value analysis indicated that the estimates were not robust against unmeasured confounding. Conclusion: According to the available real-world data, our results suggest that biological therapy effectively treats patients with rheumatoid arthritis, indicating higher effectiveness with non-TNFi and JAKi than with TNFi. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID#CRD42020190838, identifier CRD42020190838.
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BACKGROUND: Children and youth with intellectual and developmental disabilities (IDD) experience health disparities. What is unknown is if data collected from children and youth with IDD who participate in Special Olympics is representative of children and youth with IDD who do not. OBJECTIVES: Aim 1: determine the feasibility of matching a database of registrants from Special Olympics Ontario (SOO), with population-based health services databases in Ontario, Canada housed at ICES. Aim 2: evaluate the differences between the database sources with regards to demographic variables and clinical status. METHODS: Using deterministic and probabilistic matching, registration data from SOO were matched to administrative health databases. Established algorithms were used to determine the prevalence of asthma, diabetes, and mental disorder in addition to demographic variables. RESULTS: The matching rate was over 90%; 8404 were attributed to children and youth between the ages of 0-19 years. When comparing SOO participants with IDD to non-SOO participants with IDD, children and youth who participate in SOO were, on average, older with no further differences between groups on clinical or demographic variables. When comparing those previously not identified in the health services databases (from SOO) to those with IDD identified by ICES, the SOO participants appear to use the health system less, possibly indicating a better health status. CONCLUSIONS: Research conducted on child and youth who participate in Special Olympics Ontario can be generalized to the broader population of children and youth with IDD in Canada when adjusted for age; however, care should be taken when comparing levels of overall morbidity.
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Pessoas com Deficiência , Deficiência Intelectual , Adolescente , Adulto , Criança , Pré-Escolar , Deficiências do Desenvolvimento/epidemiologia , Estudos de Viabilidade , Nível de Saúde , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/epidemiologia , Ontário/epidemiologia , Adulto JovemRESUMO
INTRODUCTION: Juvenile idiopathic arthritis (JIA) is a chronic rheumatic disease, whose multifaceted care path can lead to significant expenditure for the healthcare system. We aim to assess the real-world healthcare resource use (HCRU) and associated cost for children with JIA in a single center in Canada. METHODS: A single-center consecutive cohort of newly diagnosed patients with JIA attending the pediatric rheumatology clinic from 2011 to 2019 was identified using an administrative data algorithm and electronic medical charts. HCRU was estimated from six administrative health databases that included hospital admissions, emergency, outpatient care, practitioners' visits, medication, and laboratory and imaging tests. Costs were assigned using appropriate sources. We reported the yearly overall and JIA-associated HCRU and costs 5 years prior to and 6 years after the first visit to the pediatric rheumatologist. The Zhao and Tian estimator was used to calculate cumulative mean costs over a 6-year timeframe. Results were stratified by disease subtype. RESULTS: A total of 389 patients were identified. The yearly total overall mean costs per patient ranged between $804 and $4460 during the 5 years prior to the first visit to the pediatric rheumatologist and $8529 and $10,651 for the 6 years after. Medication cost, driven by use of biologic therapies, and outpatient visits were the greatest contributor to the total cost. The overall cumulative mean cost for 6 years of care was $48,649 per patient, while the JIA-associated cumulative mean cost was $26,820 per patient. During the first year of rheumatology care, systemic onset JIA had the highest cumulative mean overall cost, while oligoarticular JIA had the lowest cumulative mean cost. CONCLUSION: The care pathway for children with JIA can be expensive, and complex-and varies by JIA subtype. Although the yearly total mean cost per patient was constant, the distribution of costs changes over time with the introduction of biologic therapies later in the care pathway. This study provides a better understanding of the JIA costs profile and can help inform future economic studies.
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BACKGROUND: Limited studies have systematically reviewed the literature to identify and compare the various database methods and optimal thresholds for measuring medication adherence specific to adolescents and adults with asthma. In the present study, we aim to identify the methods and optimal thresholds for measuring medication adherence in population-based pharmacy databases. METHODS: We searched PubMed, Embase, International Pharmaceutical Abstracts (IPA), Web of Science, Google Scholar, and grey literature from January 1, 1998, to March 16, 2021. Two independent reviewers screened the studies, extracted the data, and assessed the quality of the studies. A quantitative knowledge synthesis was employed. RESULTS: Thirty-eight (38) retrospective cohort studies were eligible. This review identified 20 methods for measuring medication adherence in adolescent and adult asthma administrative health records. Two measures namely the medication possession ratio (MPR) and proportion of days covered (PDC) were commonly reported in 87% of the literature included in this study. From the meta-analysis, asthma patients who achieved adherence threshold of "0.75-1.00" [OR: 0.56, 95% CI: 0.41 to 0.77] and ">0.5" [OR: 0.71, 95% CI: 0.54 to 0.94] were less likely to experience asthma exacerbation. CONCLUSION: Despite their limitations, the PDC and the MPR still remain the most common measures for assessing adherence in asthma pharmacy claim databases. The evidence synthesis showed that an adherence threshold of at least 0.75 is optimal for classifying adherent and non-adherent asthma patients.
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PURPOSE: Unrecognized and untreated hyperthyroidism leads to serious clinical complications with adverse outcomes for patients and increasing costs for the health care system. Hence, adequate knowledge of the epidemiological features of such condition is desirable to plan effective interventions. The aim of our study was to estimate incidence and prevalence of hyperthyroidism in the mildly iodine-deficient Italian Region of Piedmont. METHODS: A retrospective cohort study was conducted using Administrative Health Databases of the Piedmont Region, Italy (2012-2018). Hyperthyroidism cases were defined as the subjects who had at least one of the following claims: (i) hospital discharge records with hyperthyroidism diagnosis code; (ii) exemption from co-payment for hyperthyroidism; (iii) prescription of one of the following medications: methimazole, propylthiouracil, or potassium perchlorate. RESULTS: The overall prevalence was 756 per 100,000 inhabitants [95% CI 748-764], and the overall incidence was 81 per 100,000-person year [95% CI 80-82]. The prevalence and incidence increased with age and were two-fold higher among women than men. Women also showed two distinct peaks in incidence at the age of 30 and 50; after the age of 60, the trend became similar between sexes. With regard to the geographic distribution, an increasing gradient of incidence was observed from the northern to the south-western areas of the Region. CONCLUSION: This is the first Italian study based on health databases to estimate the incidence and prevalence of hyperthyroidism in the general population. This approach can represent an inexpensive and simple method to monitor patterns of hyperthyroidism in iodine-deficient areas.
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Hipertireoidismo , Feminino , Humanos , Hipertireoidismo/epidemiologia , Incidência , Itália/epidemiologia , Masculino , Prevalência , Estudos RetrospectivosRESUMO
BACKGROUND: Use of health administrative databases is proposed for screening and monitoring of participants in randomized registry trials. However, access to these databases raises privacy concerns. We assessed patient's preferences regarding use of personal information to link their research records with national health databases, as part of a hypothetical randomized registry trial. METHODS AND RESULTS: Cardiology patients were invited to complete an anonymous self-reported survey that ascertained preferences related to the concept of accessing government health databases for research, the type of personal identifiers to be shared and the type of follow-up preferred as participants in a hypothetical trial. A total of 590 responders completed the survey (90% response rate), the majority of which were Caucasians (90.4%), male (70.0%) with a median age of 65years (interquartile range, 8). The majority responders (80.3%) would grant researchers access to health administrative databases for screening and follow-up. To this end, responders endorsed the recording of their personal identifiers by researchers for future record linkage, including their name (90%), and health insurance number (83.9%), but fewer responders agreed with the recording of their social security number (61.4%, p<0.05 with date of birth as reference). Prior participation in a trial predicted agreement for granting researchers access to the administrative databases (OR: 1.69, 95% confidence interval: 1.03-2.90; p=0.04). CONCLUSION: The majority of Cardiology patients surveyed were supportive of use of their personal identifiers to access administrative health databases and conduct long-term monitoring in the context of a randomized registry trial.
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Cardiologia/métodos , Confidencialidade , Garantia da Qualidade dos Cuidados de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Sistema de Registros , Bases de Dados Factuais , Registros de Saúde Pessoal , Humanos , Estudos RetrospectivosRESUMO
BACKGROUND: Population-based registries implement the comprehensive collection of all disease events that occur in a well-characterized population within a certain time period and represent the preferred tools for disease monitoring at a population level. Main characteristics of a Population-based registry are to provide answers to defined research questions, also related to clinical and health policy purposes, assuring completeness of event identification, and implementing a process of case adjudication (validation) according to standardised diagnostic criteria. METHODS: The application of a standard methodology results in the availability of reliable and comparable data and facilitates the transferability of health information for research and evidence-based health policies. Although registries are extremely useful, they require considerable resources to be implemented and maintained, high cost and efforts, to produce stable and reliable indicators. RESULTS: Thanks to available health information and information technology, current administrative databases on hospital admissions and discharges, medication use, in-patient care utilization, surgical operations, drug dispensations, ticket exemption and invasive procedures are increasingly available. They represent basic sources of information for implementing Population-based registries.Main strengths and limitations of Population-based registries are described taking into consideration the example of cardiovascular diseases, as well as future challenges and opportunities for implementing Population-based registries at European level. CONCLUSIONS: The integration of population-based registries and current administrative health databases may help to complete the picture of the disease rebuilding the evolution of the disease as a continuum from the onset to the possible consequent complications.
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PURPOSE: The purpose of the present study is to determine predictors of attendance at a network of publicly funded specialized survivor clinics by a population-based cohort of adult survivors of childhood cancer. METHODS: We conducted a retrospective study linking data on eligible patients identified in a provincial pediatric cancer registry with health administrative databases to determine attendance at five specialized survivor clinics in the Canadian province of Ontario between 1999 and 2012. Eligible survivors were treated for cancer at ≤18 years between 1986 and 2005, had survived ≥5 years from their most recent pediatric cancer event, and contributed ≥1 year of follow-up after age 18 years. We assessed the impact of cancer type, treatment intensity, cumulative chemotherapy doses, radiation, socioeconomic status, distance to nearest clinic, and care from a primary care physician (PCP) on attendance using recurrent event multivariable regression. RESULTS: Of 7482 children and adolescents treated for cancer over the study period, 3972 were eligible for study inclusion, of which 3912 successfully linked to administrative health data. After a median of 7.8 years (range 0.2-14.0) of follow-up, 1695/3912 (43.3 %) had attended at least one adult survivor clinic visit. Significantly increased rates of attendance were associated with female gender, higher treatment intensity, radiation, higher alkylating agent exposure, higher socioeconomic status, and an annual exam by a PCP. Distance significantly impacted attendance with survivors living >50 km away less likely to attend than those living within 10 km (relative rate 0.77, p = 0.003). CONCLUSION: Despite free access to survivor clinics, the majority of adult survivors of childhood cancer do not attend. IMPLICATIONS FOR CANCER SURVIVORS: Alternate models of care need to be developed and assessed, particularly for survivors living far from a specialized clinic and those at lower risk of developing late effects.