thanks for helping!

I am testing a repeated measures dataset (multiple rows per participant) in a multilevel Cox regression with time-varying predictors. I'm trying to see if effects vary by assessor. My variables are:

  • ID: participant ID (time independent)
  • dynamic: repeated measure test score (time dependent)
  • assessor: person doing assessment, nesting variable (time independent)
  • intervention : binary, whether or not dynamic was followed by intervention (time dependent)
  • entry: beginning of prediction interval (time dependent)
  • exit: end of prediction interval (time dependent)
  • flag: if survival event occurred during interval (time dependent)

I want to eventually test if interactions between dynamic and intervention vary by assessor, but starting with univariate tests, I have two questions.

First: I keep seeing two separate ways of specifying that I want the slope (of "dynamic")to vary by assessor. What is the difference between




Second: Does it make sense to test a random coefficient for a binary variable? Would that use different syntax? Would random effects be interpretable or would I go by chi-square of the models?


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.