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Assessing time‐by‐covariate interactions in proportional hazards regression models using cubic spline functions

Hess, Kenneth R.·1994·Statistics in Medicine

Abstract

Proportional hazards (or Cox) regression is a popular method for modelling the effects of prognostic factors on survival. Use of cubic spline functions to model time‐by‐covariate interactions in Cox regression allows investigation of the shape of a possible covariate‐time dependence without having to specify a specific functional form. Cubic spline functions allow one to graph such time‐by‐covariate interactions, to test formally for the proportional hazards assumption, and also to test for non‐linearity of the time‐by‐covariate interaction. The functions can be fitted with existing software using relatively few parameters; the regression coefficients are estimated using standard maximum likelihood methods.

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Metadata

Authors
Hess, K. R.
Venue
Statistics in Medicine
Publisher
Wiley
Published
1994-05-30
Volume
13
Issue
10
Pages
1045-1062
ISSN
  • 0277-6715 (ISSN-L)
  • 1097-0258
OpenAlex
W2097239572
Cited by
212
References
1
FWCI
2.49
Type
journal article
Language
en
Open access
closed

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CoChat. (2026). Citation check: Assessing time‐by‐covariate interactions in proportional hazards regression models using cubic spline functions. https://app.cochat.ai/papers/10.1002/sim.4780131007
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Hess, K. R. (1994). Assessing time‐by‐covariate interactions in proportional hazards regression models using cubic spline functions. Statistics in Medicine. https://doi.org/10.1002/sim.4780131007

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