ArticleThe Journal of arthroplasty2021
Immortal Time Bias in the Analysis of Time-to-Event Data in Orthopedics.
Article in The Journal of arthroplasty, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
9 citing papers in PubMed, 15 citations in OpenAlex.
- Assessing Impact of Concomitant Use of Proton Pump Inhibitors and Clopidogrel on Incidence of Major Adverse Cardiovascular Events: A Retrospective Cohort Study.Pharmacoepidemiology and drug safety · 2025Article
- Methodological Considerations Regarding the Article "Association Between Non-Benzodiazepine Hypnotics and Tinnitus: A Nationwide Cohort Study in Taiwan" [Letter].Nature and science of sleep · 2025Article
- Article
- Discordance in Published 30-Day Readmission Rates Following Primary Total Hip and Total Knee Arthroplasty: Centers for Medicare and Medicaid Services (CMS) Versus the National Surgical Quality Improvement Program (NSQIP).The Iowa orthopaedic journal · 2024Article
- Survival analyses and their applications in orthopaedics.Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA · 2023Review
- The influence of immortal time bias in observational studies examining associations of antifibrotic therapy with survival in idiopathic pulmonary fibrosis: A simulation study.Frontiers in medicine · 2023Article
- Living With Survival Analysis in Orthopedics.The Journal of arthroplasty · 2021Article
- Identifying and avoiding design related biases in observational studies using the target trial framework.BMJ medicineArticle
- Metformin exposure after glioblastoma diagnosis and mortality: A large population-based study.Neuro-oncology advancesArticle
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors at 2 institutions in 1 country.
Funding
Abstract
Many outcomes in arthroplasty research are analyzed as time-to-event outcomes using survival analysis methods. When comparison groups are defined after a time-delayed exposure or intervention, a period of immortal time arises and can lead to biased results. In orthopedics research, immortal time bias often arises when a minimum amount of follow-up is required for study inclusion or when comparing outcomes in staged bilateral vs unilateral arthroplasty patients. We present an explanation of immortal time and the associated bias, describe how to correctly account for it using proper data preparation and statistical techniques, and provide an illustrative example using real-world arthroplasty data. We offer practical guidelines for identifying and properly handling immortal time to avoid bias. Please visit the followinghttps://youtu.be/58p8w5o-ci4for a video that explains the highlights of the paper in practical terms.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.