Clinical Epidemiology最新文献

{"title":"From Concept to Implementation: A Policy and Standards Roadmap for a Global Medical Record System for Travelers with Chronic Disease.","authors":"Anjum Khurshid, Jennifer L Winkler, Mohammad Jafari, Henrik Toft Sorensen","doi":"10.2147/CLEP.S626524","DOIUrl":"https://doi.org/10.2147/CLEP.S626524","url":null,"abstract":"<p><p>International travel by people with multimorbidity and polypharmacy is increasing, and clinicians who treat these patients abroad seldom have access to accurate and current information about them. Mechanisms for cross-border exchange do exist: the International Patient Summary (IPS), European cross-border health services, and national patient portals all move summary clinical data between jurisdictions. What none of them yet provides is automated abstraction of decades of longitudinal records into a short summary, and reliable determination of which diagnoses are active and which medications are current. They also do not provide consistent deployment across jurisdictions that record and code data differently. Sørensen (2022) established the clinical case for a Global Medical Record System (GMRS) and outlined its core data elements. We argue that four recent developments provide a window of policy opportunity: COVID-19 vaccination credentials, which showed that portable health data can be deployed at population scale; formalization of the HL7 IPS as an ISO standard with an implementation guide (FHIR IG); regulatory mandates for health data interoperability in the United States and the European Union; and an ongoing transatlantic collaboration aimed at mapping a GMRS algorithm onto those standards. Herein we make a policy case for coordinated international action, describe the standards pathway of mapping the GMRS to the FHIR IPS and United States Core Data for Interoperability (USCDI), and propose a structured maturation pathway for research and validation via a Denmark-United States collaboration. The GMRS would add to the IPS an abstraction layer that decides which of a patient's accumulated entries belong in the summary. We present this as a proposed roadmap and policy argument as the GMRS algorithm has not yet undergone formal validation which would be required before actual deployment.</p>","PeriodicalId":10362,"journal":{"name":"Clinical Epidemiology","volume":"18 ","pages":"626524"},"PeriodicalIF":4.3,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13659062/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149178758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stable Overall Volume, Shifting Structure: Nine Years of Paediatric Outpatient Prescribing and Dispensing in Finland, 2017-2025.","authors":"Péter Csonka, Juho Leppänen, Hanna Koskinen, Heini Kari","doi":"10.2147/CLEP.S636160","DOIUrl":"https://doi.org/10.2147/CLEP.S636160","url":null,"abstract":"<p><strong>Background: </strong>Paediatric outpatient prescribing varies across Europe, and whole-population data spanning the COVID-19 pandemic remain scarce. We characterised trends in dispensation prevalence, age and sex patterns, therapeutic class shifts, and prescriber channels for all children in Finland, 2017-2025.</p><p><strong>Methods: </strong>We conducted a nationwide registry-based drug utilisation study of all children under 18 years resident in Finland in 2017-2025, using individual-level data from the Kanta Prescription Centre. Drugs were classified by ATC code. Annual prevalence was the proportion of the year-end resident child population with at least one dispensation; age and sex patterns were modelled with sex-specific quasi-Poisson generalised additive models.</p><p><strong>Results: </strong>Over 2017-2025, 1,324,517 children received 21.1 million dispensations. Mean annual dispensation prevalence was 50.4%, or 45.1% when systemic antibiotics were excluded. Anti-infective dispensing (ATC J) fell from 298 to 237 per 1,000 children and did not return to pre-pandemic levels. Nervous system drug prevalence (ATC N) rose from 107 to 155 per 1,000, driven mainly by adolescents (lisdexamfetamine +709%, sertraline +305%, methylphenidate +207%). Boys predominated to age 13 (boy-to-girl ratio peaking near 1.5); by age 17, girls received roughly 1.7 times as many dispensations as boys. The adolescent gap persisted after excluding hormonal contraceptives, and boys showed the larger relative rise at ages 14-17. The public-sector share of prescriptions fell from 62.1% to 57.9%, with prescribing to children under 6 years shifting from public general practice to private paediatrics.</p><p><strong>Conclusion: </strong>Overall paediatric dispensation volume in Finland was broadly stable across 2017-2025, but the underlying structure changed substantially. Antibiotic stewardship gains held, central nervous system medicine use rose continuously, and the channel mix shifted toward private paediatric care for younger children. If access to private care depends on family resources, this shift may widen inequalities in children's access to prescribed medicines, although socioeconomic factors were not assessed here.</p>","PeriodicalId":10362,"journal":{"name":"Clinical Epidemiology","volume":"18 ","pages":"636160"},"PeriodicalIF":4.3,"publicationDate":"2026-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13635632/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149104997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Drug-Induced Orthostatic Hypotension in UK Primary Care: A Self-Controlled Case Series Study.","authors":"Cini Bhanu, Irene Petersen, Mine Orlu, Daniel Davis, Reecha Sofat, Kate Walters","doi":"10.2147/CLEP.S593981","DOIUrl":"10.2147/CLEP.S593981","url":null,"abstract":"<p><strong>Background: </strong>Drug-induced orthostatic hypotension (OH) is common and increasing worldwide with rising polypharmacy. Real-world evidence is crucial for safe prescribing. We examined the risk of OH associated with commonly prescribed drugs in UK primary care among adults aged ≥60 years.</p><p><strong>Methods: </strong>This was a self-controlled case series using routinely collected UK primary care data from the IQVIA Medical Research Database (IMRD). Individuals with an OH diagnosis and drug exposure between 1 January 2000 and 31 December 2018 were included. Drug classes potentially causing OH were coded by British National Formulary sub-chapters. Incidence rate ratios (IRRs) of OH were compared across a 90-day pre-exposure period and three post-prescription risk periods (day 1-28; day 29-56; day 57+) against periods outside these risk periods (reference period).</p><p><strong>Results: </strong>Of 2,597,077 eligible individuals, 41,005 (1.6%) had a first-recorded OH diagnosis; 51% were women. Increased OH risk was associated with initiation of all cardiovascular system (CVS), central nervous system (CNS), and urinary retention drugs, and some anti-diabetic drugs. Across most classes, OH risk peaked sharply after initiation (day 1-28) and then declined. Drugs causing OH via sympathetic inhibition, diuresis, or mixed mechanisms had the highest risk (eg, uroselective alpha-blockers: IRR 4.94, 95% CI 4.38-5.58) during day 1-28. Vasodilation-causing drugs had lower risk (eg, calcium-channel blockers: IRR 1.88, 95% CI 1.58-2.23). An increased OH risk was observed before drug initiation when the indication was an independent OH cause (eg, loop diuretics for heart failure: IRR 1.74, 95% CI 1.59-1.91).</p><p><strong>Conclusion: </strong>This study provides insights into OH risk across 17 drug classes in older adults, considering timing, drug system, and mechanism. Consistent trends show that OH risk peaked in the first 4 weeks post-initiation and reduced thereafter. Drugs causing OH through sympathetic inhibition, diuresis, or mixed mechanisms carried the greatest risk. Elevated OH risk in the pre-exposure period may suggest underlying indications that independently cause OH. These findings have important implications for primary care.</p>","PeriodicalId":10362,"journal":{"name":"Clinical Epidemiology","volume":"18 ","pages":"593981"},"PeriodicalIF":4.3,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13618310/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Associations Between Body Mass Index Trajectories and Healthcare Utilization and Costs Among Patients with Type 2 Diabetes in Finland.","authors":"Zhiting Wang, Piia Lavikainen, Katja Wikström, Janne Martikainen, Tiina Laatikainen","doi":"10.2147/CLEP.S590966","DOIUrl":"10.2147/CLEP.S590966","url":null,"abstract":"<p><strong>Purpose: </strong>We assessed how body mass index (BMI) trajectories were associated with healthcare utilization and costs in patients with type 2 diabetes (T2D).</p><p><strong>Patients and methods: </strong>In this retrospective cohort study, electronic health records from all public healthcare in North Karelia, Finland, were used. Patients newly diagnosed with T2D in 2011-2014 were included. The 10-year BMI trajectories since T2D diagnosis were estimated by growth mixture modeling. Time trends of healthcare utilization and costs from 2012 to 2024, and accumulated healthcare utilization over time within and between BMI trajectories were analyzed using age- and sex-adjusted regression models. Group differences in accumulated healthcare costs with 95% confidence intervals (Cls) were estimated using nonparametric bootstrapping.</p><p><strong>Results: </strong>Among 3539 patients, 2750 (77.7%) were classified as having stable, 517 (14.6%) increasing, and 272 (7.7%) decreasing BMI trajectories. From 2012 to 2024, mean annual number of specific healthcare utilization and costs increased within BMI trajectories. Compared with the stable BMI trajectory, increasing BMI was associated with 9-55% higher healthcare unitization rates, particularly for all-cause, T2D-related, microvascular, mental health, and inpatient outcomes, over a mean follow-up of 10.8 years (rate ratios ranging from 1.09 to 1.55; 95% CI 1.01-1.86). A similar pattern was observed for accumulated healthcare costs, with mean differences (95% CI) of 6065 € (2741-9795 €) for all causes, 559 € (86 -1174 €) for T2D, 136 € (18-246 €) for microvascular complications, and 312 € (140-509 €) for mental health, and 6477 € (1213-11,889 €) for inpatient stays. However, decreasing BMI was associated with higher accumulated healthcare utilization and costs for macrovascular, mental health, and inpatient outcomes.</p><p><strong>Conclusion: </strong>Our findings emphasize the importance of monitoring and managing BMI in patients with T2D. However, the observed associations with the decreasing BMI trajectory should be interpreted with caution, as declining BMI may reflect unintentional weight loss.</p>","PeriodicalId":10362,"journal":{"name":"Clinical Epidemiology","volume":"18 ","pages":"590966"},"PeriodicalIF":4.3,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13616150/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149069330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"When to Start, How to Classify, and Whom to Include: A Methodological Assessment and Illustrative Example of the Clone-Censor-Weight Approach for Evaluating Intervention Timing in Observational Studies.","authors":"Sia Kromann Nicolaisen, Reimar Wernich Thomsen, Lars Pedersen","doi":"10.2147/CLEP.S618946","DOIUrl":"10.2147/CLEP.S618946","url":null,"abstract":"<p><strong>Introduction: </strong>Observational studies evaluating the effect of timing of an intervention, such as early versus deferred drug treatment initiation or short versus long treatment duration, often suffer from bias due to misalignment between eligibility assessment, intervention assignment, and start of follow-up. The clone-censor-weight approach aligns these time points and allows for estimation of treatment effects under predefined timing strategies.</p><p><strong>Methods: </strong>We assess the clone-censor-weight methodology and illustrate its application in an observational registry-based study of individuals with newly diagnosed diabetes, comparing infection risks under four strategies for initiation of glucose-lowering treatment: initiation within 15 days (Strategy 1), 15 days to 3 months (Strategy 2), 3 to 6 months (Strategy 3), or 6 to 12 months (Strategy 4) after diagnosis.</p><p><strong>Results: </strong>The clone-censor-weight approach established the diabetes diagnosis as the index date across all strategies. The study example included 33,857 individuals with newly diagnosed diabetes. They were cloned and assigned to all four treatment strategies, where 6439 (19.0%) clones adhered to Strategy 1, 8419 (24.9%) to Strategy 2, 5550 (16.2%) to Strategy 3, and 7539 (22.3%) to Strategy 4. The weighted absolute 5-year risks of infection were 67.0% (95% CI 65.3-68.5) for Strategy 1, 65.7% (95% CI 64.1-66.9) for Strategy 2, 66.8% (95% CI 61.8-71.9) for Strategy 3, and 67.8% (95% CI 62.8-72.7) for Strategy 4.</p><p><strong>Discussion: </strong>We have assessed the methodology and illustrated the clone-censor-weight approach in a study example evaluating intervention timing. Censoring weights should account for selection bias, estimating per-protocol effects under full adherence, but methodological challenges remain in ensuring that the weights adequately reflect both the target intervention strategies and the population they are intended to represent.</p>","PeriodicalId":10362,"journal":{"name":"Clinical Epidemiology","volume":"18 ","pages":"618946"},"PeriodicalIF":4.3,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615852/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149058686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Effectiveness of Laparoscopic versus Open Colectomy on 5-Year Overall Survival in Non-Metastatic Colon Cancer: A Target Trial Emulation Study Using Retrospective Cohort Data from a Cancer Registry.","authors":"Semaw Ferede Abera, Gabriele Robers, Anika Kästner, Ulrike Stentzel, Kerstin Weitmann, Wolfgang Hoffmann","doi":"10.2147/CLEP.S626070","DOIUrl":"10.2147/CLEP.S626070","url":null,"abstract":"<p><strong>Background: </strong>The clinical acceptance of laparoscopic colectomy (LC) as a standard alternative treatment for colon cancer hinges primarily on evidence of favorable long-term oncological outcome. The aim of this study was to compare the 5-year overall survival (OS) between stage I-III colon cancer patients who underwent either LC or open colectomy (OC).</p><p><strong>Materials and methods: </strong>A target trial emulation (TTE) design was implemented using statewide retrospective cohort data from the Mecklenburg-Western Pomerania Cancer Registry spanning 2008 to 2018. The causal interpretation of TTE relied on the assumptions of consistency, conditional exchangeability, and positivity. The Royston-Parmar parametric survival model was applied to estimate the hazard ratio with bootstrapped 95% confidence interval (95% CI). This was complemented by differences in estimates of restricted mean survival time (RMST). Sensitivity analyses, including the E-value method, were conducted to assess the robustness of the estimated treatment effect. Three traditional (fully adjusted, change-in-estimate, and Directed Acyclic Graph-guided) Cox models were performed for comparison purposes.</p><p><strong>Results: </strong>We included 1265 patients, of whom 30% (n= 380) received LC. The estimated HR for 5-year OS comparing LC with OC was 0.81 (95% CI: 0.60, 1.08). RMST differences for OS favored LC, but the effects were small: 0.12 months (95% CI: -0.10, 0.34), 0.36 months (95% CI: -0.15, 0.87), and 1.20 months (95% CI: -0.20, 2.60) up to 1-, 3-, and 5-years, respectively. Sensitivity analyses generally confirmed the robustness of the results. Traditional Cox models showed a survival advantage for LC, but all were affected by bias.</p><p><strong>Conclusion: </strong>This study found comparable 5-year OS between LC and OC. The traditional Cox models spuriously overestimated the survival advantage of LC. TTE can provide useful real-world evidence for comparative effectiveness in surgical oncology, particularly when randomized evidence is limited, but it cannot replace well-conducted RCTs.</p>","PeriodicalId":10362,"journal":{"name":"Clinical Epidemiology","volume":"18 ","pages":"626070"},"PeriodicalIF":4.3,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13592361/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149016017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strengthening Clinical Epidemiology in Somalia: Challenges, Opportunities, and Future Directions.","authors":"Ibrahim Abubakar Abdi","doi":"10.2147/CLEP.S632448","DOIUrl":"10.2147/CLEP.S632448","url":null,"abstract":"<p><p>Clinical epidemiology constitutes a foundational pillar of evidence-based medicine and health system strengthening. This commentary examines the current state of clinical epidemiology in Somalia and is intended to stimulate scholarly dialogue and policy action among Somali and international health stakeholders, situating the discussion within the country's broader trajectory of health system recovery and evidence-based decision-making. Despite Somalia's substantial disease burden, clinical epidemiology remains critically underdeveloped, constrained by structural, infrastructural, academic, and governance-related challenges that we delineate in detail. Simultaneously, we identify emerging opportunities - including growing international partnerships, digital health innovations, diaspora engagement, and nascent academic infrastructure - that may catalyse progress toward locally generated research capacity. We argue that deliberate investment in epidemiological capacity, curriculum reform in health sciences education, strengthened national health information systems, and clearer research governance mechanisms are prerequisites for building a robust clinical epidemiology enterprise in Somalia, and we propose priority actions spanning postgraduate training programmes, health information system investment, and the development of a nationally owned research agenda.</p>","PeriodicalId":10362,"journal":{"name":"Clinical Epidemiology","volume":"18 ","pages":"632448"},"PeriodicalIF":4.3,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13593576/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149024218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Risk of Cancer After a Hospital Contact for Dyspnea: A Nationwide Danish Cohort Study.","authors":"Usama Sikandar, Søren Korsgaard Martiny, Dóra Körmendiné Farkas, Eyal Oren, Hans Erik Bøtker, Henrik Toft Sørensen","doi":"10.2147/CLEP.S630951","DOIUrl":"10.2147/CLEP.S630951","url":null,"abstract":"<p><strong>Purpose: </strong>Dyspnea may be a symptom of undiagnosed cancer, but this association remains poorly understood. We examined cancer incidence among patients with a hospital contact for dyspnea compared with the general population.</p><p><strong>Patients and methods: </strong>Using nationwide Danish registries, we identified all patients with a hospital contact for dyspnea during 1994-2022 and followed them until a cancer diagnosis, emigration, death, or December 31, 2022. We computed cumulative cancer incidence treating death as a competing event, and standardized incidence ratios (SIR) with 95% confidence intervals (CIs), as the observed number of cancers relative to the expected number based on national cancer incidence rates.</p><p><strong>Results: </strong>Among 266,044 patients with dyspnea, 27,884 subsequent cancers were observed. The 1-year cumulative incidence of any cancer was 3.8%, rising to 12.7% at 10 years. At one year, cumulative incidence was highest for lung (1.4%), gastrointestinal (0.6%), hematological (0.5%), and prostate (0.5%) cancers. The 1-year SIR for any cancer was 3.17 (95% CI, 3.11-3.23), elevated across all cancer types, and highest for pleural (17.57; 95% CI, 15.32-20.05), lung (9.34; 95% CI, 9.05-9.64), and hematological (4.17; 95% CI, 3.94-4.41) cancers. Beyond one year, cancer incidence remained elevated (SIR, 1.14; 95% CI, 1.12-1.16), particularly for lung cancer (SIR, 1.56; 95% CI, 1.50-1.61).</p><p><strong>Conclusion: </strong>Patients with a hospital contact for dyspnea had a markedly higher incidence of thoracic and non-thoracic cancers than the general population, particularly during the first year of follow-up. These findings support consideration of an underlying cancer across organ systems as part of the diagnostic evaluation of patients presenting with dyspnea.</p>","PeriodicalId":10362,"journal":{"name":"Clinical Epidemiology","volume":"18 ","pages":"630951"},"PeriodicalIF":4.3,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13589962/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149012053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"One-Year Target Lesion Revascularization Prediction Shows Uncertain Incremental Accuracy After Competing-Death Exclusion [Letter].","authors":"Jiaqing Liu","doi":"10.2147/CLEP.S652901","DOIUrl":"10.2147/CLEP.S652901","url":null,"abstract":"","PeriodicalId":10362,"journal":{"name":"Clinical Epidemiology","volume":"18 ","pages":"652901"},"PeriodicalIF":4.3,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13588120/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149007704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trends in Tympanostomy Tube Insertion Among Children Aged 0-12 Years: A Register-Based Cohort Study in Denmark (2003-2023).","authors":"Michael Lüscher, Nikolaj B Pedersen, Steven A W Andersen, Thomas Qvist Barrett, Peter Tingsgaard, Lene Dahl Siggaard, Per Kallestrup, Anders Prior","doi":"10.2147/CLEP.S619479","DOIUrl":"https://doi.org/10.2147/CLEP.S619479","url":null,"abstract":"<p><strong>Purpose: </strong>Tympanostomy tube insertion (TTI) is one of the most frequently performed surgical procedures in children. Yet, substantial temporal and geographical variations persist across comparable healthcare systems. We aimed to describe nationwide trends in TTI among Danish children in 2003-2023, with particular attention to changes associated with the COVID-19 pandemic and regional differences in treatment patterns.</p><p><strong>Patients and methods: </strong>In this nationwide register-based cohort study, we included all Danish children aged 0-12 years between 2003 and 2023 (n=2,243,285). Data on TTIs were obtained from the Danish National Patient Register and the Danish National Health Service Register. Incidence rates, cumulative proportions, age at first procedure, and regional variation were analyzed using calendar year and birth cohorts.</p><p><strong>Results: </strong>We identified 704,013 TTI procedures performed in 371,818 children; 96.6% were conducted in ear, nose, and throat (ENT) practices. Annual procedure numbers peaked at 40,826 cases in 2010 and declined steadily to 29,846 cases in 2019. A marked reduction occurred during the COVID-19 pandemic in 2020-2021, followed by a rebound to the pre-pandemic level in 2022 and a further increase to 35,024 procedures in 2023. The proportion of children receiving at least one TTI increased from 3.11% in 2019 to 3.67% in 2023 (proportion ratio (PR) 1.18, 95% confidence interval (CI) 1.16-1.20). Median age at first TTI was 18.1 months, with persistent regional variation; rates were highest in the North Denmark Region and lowest in the Capital Region of Denmark.</p><p><strong>Conclusion: </strong>TTI rates in Danish children decreased substantially over the past decade, declined further during the COVID-19 pandemic, and subsequently returned to pre-pandemic levels. Persistent regional differences indicate variation in clinical practice that cannot be explained solely by underlying disease epidemiology. The long-term effects of the pandemic on TTI utilization remain uncertain.</p>","PeriodicalId":10362,"journal":{"name":"Clinical Epidemiology","volume":"18 ","pages":"619479"},"PeriodicalIF":4.3,"publicationDate":"2026-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13580447/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148988548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}