ArticleBMC medical research methodology2019
Methods of sample size calculation in descriptive retrospective burden of illness studies.
Article in BMC medical research methodology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 67 papers, 2 of them syntheses that pooled it.
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Who cites it
67 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- A systematic review of the quality of conduct and reporting of survival analyses of tuberculosis outcomes in Africa.BMC medical research methodology · 2021Pooled it
- Pooled it
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- Explainable machine learning model for early prediction of ICU death in chronic heart failure with pulmonary infection.BMC medical informatics and decision making · 2026Article
- Economic burden borne by patients due to diagnostic delays in inflammatory bowel disease: Insights from a survey of newly diagnosed patients.Indian journal of gastroenterology : official journal of the Indian Society of Gastroenterology · 2026Observational
- Patient Safety Events Among People from Ethnic Minority Backgrounds: A Retrospective Medical Record Review of Australian Cancer Services.Journal of racial and ethnic health disparities · 2026Article
- The economic burden of managing diabetes mellitus in children in Sudan: a cross-sectional study.Cost effectiveness and resource allocation : C/E · 2026Article
- Is Emergency Department Care for Low Back Pain Meeting Contemporary Standards? A Medical Record Review.Emergency medicine Australasia : EMA · 2026Article
- Impact of growth hormone treatment on childhood growth patterns in Kermanshah: A retrospective cohort study.Journal of education and health promotion · 2026Article
- Antibiotic prescribing appropriateness among critically ill patients at a single tertiary care center in the United Arab Emirates: a retrospective cohort study.Frontiers in health services · 2026Article
- Young-onset stroke in the UAE: A single-centre retrospective analysis of risk factors and outcomes.PloS one · 2026Article
- The effect of nurse-led bladder training on urinary tract outcomes after kidney transplantation.Frontiers in nephrology · 2026Article
- Healing Outcomes in Diabetic Foot Ulcers Managed Within a Structured Multidisciplinary Care Model: A Retrospective Study.Journal of diabetes research · 2026Article
- Comparison of pre-treatment systemic inflammation indices (systemic immune-inflammation index, systemic inflammation response index, and inflammatory benchmark index) in predicting mortality risk in patients with pancreatic cancer.Contemporary oncology (Poznan, Poland) · 2026Article
- Two-years clinical course of pain intensity and symptom satisfaction for latent classes in older adults with back pain.BMC musculoskeletal disorders · 2025Observational
- Unsupervised Coverage Sampling to Enhance Clinical Chart Review Coverage for Computable Phenotype Development: Simulation and Empirical Study.JMIR medical informatics · 2025Article
- Analysis of human disease burden, determinants of treatment costs and affordability perceptions in the Rwenzori region, Uganda using DALYs, OLS and Bayesian regression.Cost effectiveness and resource allocation : C/E · 2025Article
- Article
- Direct medical cost of first-ever acute ischemic stroke in malaysia: a retrospective cohort study.Scientific reports · 2025Article
- Evaluation of routine care of prurigo nodularis in Germany: retrospective chart review study (ADVANCE PN).Journal der Deutschen Dermatologischen Gesellschaft = Journal of the German Society of Dermatology : JDDG · 2025Article
7 more citing papers are in PubMed but not listed here.
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Abstract
backgroundObservational burden of illness studies are used in pharmacoepidemiology to address a variety of objectives, including contextualizing the current treatment setting, identifying important treatment gaps, and providing estimates to parameterize economic models. Methodologies such as retrospective chart review may be utilized in settings for which existing datasets are not available or do not include sufficient clinical detail. While specifying the number of charts to be extracted and/or determining whether the number that can feasibly extracted will be clinically meaningful is an important study design consideration, there is a lack of rigorous methods available for sample size calculation in this setting. The objective of this study was to develop recommended sample size calculations for use in such studies.
methodsCalculations for identifying the optimal feasible sample size calculations were derived, for studies characterizing treatment patterns and medical costs, based on the ability to comprehensively observe treatments and maximize precision of resulting 95% confidence intervals. For cost outcomes, if the standard deviation is not known, the coefficient of variation cv can be used as an alternative. A case study of a chart review of advanced melanoma (MELODY) was used to characterize plausible values for cv in a real-world example.
resultsAcross sample sizes, any treatment given with greater than 1% frequency has a high likelihood of being observed. For a sample of size 200, and a treatment given to 5% of the population, the precision of a 95% confidence interval (CI) is expected to be ±0.03. For cost outcomes, for the median cv value observed in the MELODY study (0.72), a sample size of approximately 200 would be required to generate a 95% CI precise to within ±10% of the mean.
conclusionThis study presents a formal guidance on sample size calculations for retrospective burden of illness studies. The approach presented here is methodologically rigorous and designed for practical application in real-world retrospective chart review studies.
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