Build a survival formula safely via jmvcore::asFormula

Wraps jmvcore::asFormula with the function allow-list extended to cover common survival modelling helpers (Surv, strata, cluster, frailty, tt, pspline, ns, bs, I, const, finegray). Use this instead of base stats::as.formula() in survival / Cox / Fine-Gray paths so the formula goes through jmvcore's allow-listed parser.

Usage

.asSurvivalFormula(x, env = parent.frame())

Arguments

x

A character formula string (e.g. "survival::Surv(t, d) ~ x").

env

Environment to attach to the returned formula. Defaults to the calling frame, which is what downstream re-evaluation needs.

Value

A parsed formula object.

Details

The returned formula's environment is set to the CALLER's frame. asFormula otherwise leaves it pointing at its own evaluation frame, which does not hold the caller's mydata. Model fitting still works, because coxph(fml, data=) is handed the data directly — but any method that later re-evaluates the model call does not get it. cox.zph() is the visible casualty: ticking "Proportional hazards assumption" aborted the entire analysis with "object 'mydata' not found", taking every other result down with it.