The DOI matches its Crossref record; 3 of the 3 references it cites were found in a registry or an index.
Time-varying covariates and coefficients in Cox regression models
Open accessAbstract
Time-varying covariance occurs when a covariate changes over time during the follow-up period. Such variable can be analyzed with the Cox regression model to estimate its effect on survival time. For this it is essential to organize the data in a counting process style. In situations when the proportional hazards assumption of the Cox regression model does not hold, we say that the effect of the covariate is time-varying. The proportional hazards assumption can be tested by examining the residuals of the model. The rejection of the null hypothesis induces the use of time varying coefficient to describe the data. The time varying coefficient can be described with a step function or a parametric time function. This article aims to illustrate how to carry out statistical analyses in the presence of time-varying covariates or coefficients with R.
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“To handle PH violations, a time-dependent coefficients method with a step function was applied [8].”
From Pediatric traumatic brain injury and later psychotic syndromes in Finland (2025) · cites this paper as [8]
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Cites
Regression Models and Life-Tables
Cox, D. R. (1972) · Journal of the Royal Statistical Society Series B: Statistical Methodology · doi:10.1111/j.2517-6161.1972.tb00899.x · Cited by 39,793
Modeling Survival Data: Extending the Cox Model
Therneau, T. M., & Grambsch, P. M. (2000) · Statistics for Biology and Health · doi:10.1007/978-1-4757-3294-8 · Cited by 8,674
Proportional hazards tests and diagnostics based on weighted residuals
GRAMBSCH, P. M., & THERNEAU, T. M. (1994) · Biometrika · doi:10.1093/biomet/81.3.515 · Cited by 5,885
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Depressive symptoms predict clinical recurrence of inflammatory bowel disease
Jordi, S. B. U., Lang, B. M., Auschra, B., von Känel, R., Biedermann, L., Greuter, T., Schreiner, P., Rogler, G., Krupka, N., Sulz, M. C., et al. (2022) · Inflammatory Bowel Diseases · doi:10.1093/ibd/izab136 · Cited by 41
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Zhang, Z., Chen, L., Sun, B., Ruan, Z., Pan, P., Zhang, W., Jiang, X., Zheng, S., Cheng, S., Xian, L., et al. (2024) · Nature Communications · doi:10.1038/s41467-024-53239-9 · Cited by 37
Self-citationAnticoagulant therapy for splanchnic vein thrombosis: an individual patient data meta-analysis
Candeloro, M., Valeriani, E., Monreal, M., Ageno, W., Riva, N., Lopez-Reyes, R., Peris, M. L., Beyer Westendorf, J., Schulman, S., Rosa, V., et al. (2022) · Blood Advances · doi:10.1182/bloodadvances.2022007961 · Cited by 36
Pediatric traumatic brain injury and later psychotic syndromes in Finland
Laaksonen, J., Ponkilainen, V., Möttönen, J., Mattila, V. M., & Kuitunen, I. (2025) · European Journal of Pediatrics · doi:10.1007/s00431-025-06224-3 · Cited by 4
Metadata
- Authors
- Zhang, Z., Reinikainen, J., Adeleke, K. A., Pieterse, M. E., & Groothuis-Oudshoorn, C. G. M.
- Venue
- Annals of Translational Medicine
- Publisher
- AME Publishing Company
- Published
- 2018-04
- Volume
- 6
- Issue
- 7
- Pages
- 121-121
- ISSN
- 2305-5839 (ISSN-L)
- 2305-5847
- OpenAlex
- W2793750436
- Cited by
- 811
- References
- 3
- FWCI
- 36.68
- Type
- journal article
- Language
- en
- Open access
- hybrid
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- Zhang, Z., Reinikainen, J., Adeleke, K. A., Pieterse, M. E., & Groothuis-Oudshoorn, C. G. M. (2018). Time-varying covariates and coefficients in Cox regression models. Annals of Translational Medicine. https://doi.org/10.21037/atm.2018.02.12
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.
