Hi there. i wanted to asses the assumption of cox regression . here is the baysian cox model that i fit using brms package .
fitcox = brm(time | cens(censored) ~ a + b + c + (1 | grouping_var),
data = PL, family = cox(),
warmup = 1000, iter = 2000, chains = 4,
control = list(adapt_delta = 0.95),
prior = c(set_prior(“normal(0,10)”, class = “b”)))
print(fitcox)
how can i asses the proportional hazard assumption for the model (any function that should I use?