This builds the model formula which is used inside fit_mmrm()
and provided
to mmrm::mmrm()
internally. It can be instructive to look at the resulting
formula directly sometimes.
Usage
build_formula(
vars,
cor_struct = c("unstructured", "toeplitz", "heterogeneous toeplitz", "ante-dependence",
"heterogeneous ante-dependence", "auto-regressive", "heterogeneous auto-regressive",
"compound symmetry", "heterogeneous compound symmetry")
)
Value
Formula to use in mmrm::mmrm()
.
Examples
vars <- list(
response = "AVAL", covariates = c("RACE", "SEX"),
id = "USUBJID", arm = "ARMCD", visit = "AVISIT"
)
build_formula(vars, "auto-regressive")
#> AVAL ~ RACE + SEX + ARMCD * AVISIT + ar1(AVISIT | USUBJID)
#> <environment: 0x558e9beb7f20>
build_formula(vars)
#> AVAL ~ RACE + SEX + ARMCD * AVISIT + us(AVISIT | USUBJID)
#> <environment: 0x558e9bef94e8>