Question about how to correctly interpet Cox proportional hazards model for continuous variables I'm having an hard time trying to understand how to interpret the coefficients after fitting a Cox proportional hazards (CPH) model. I think I understand it when the variables are binary, in this case, the exponentiated coefficient refers to the hazard ratio between the two classes. However, this doesn't make sense when we're talking about a continuous variable, because we can't compare two groups. I've tried looking at other examples using CPH, but every time they only use binary variables to interpret the coefficients.

You can interpret the exponentiated coefficients as the hazard ratio associated with increasing the independent variable in 1 unit. For example, if the coefficient is $\beta=0.7$, we have $\exp(\beta)\approx2.0$, so increasing the independent variable by 1 doubles the hazard function ($\text{HR}=2.0$).
Interpretation is less straightforward than in the binary case and requires you to understand the units of your data. It may make sense to rescale your independent variables, so that 1 unit corresponds to something like 1 standard deviation or 10 years of age.
