We appreciate Testa and colleagues' comments regarding our article. As they point out, an underlying assumption of Cox survival models is the proportionality of hazards for the covariates.1 As stated in our article, we assessed the validity of this assumption for each of the covariates, including indication for testing, and found the assumption to be appropriate.2
Peterson PN, Masoudi FA. The Hurdles of Translating a Single-Center Observation Into Practice—Reply. Arch Intern Med. 2008;168(15):1720. doi:10.1001/archinte.168.15.1720
Customize your JAMA Network experience by selecting one or more topics from the list below.
Create a personal account or sign in to: