This function is used to define the names of key variables within the data.frame's
that are provided as input arguments to draws() and ancova().
Usage
set_vars(
subjid = "subjid",
visit = "visit",
outcome = "outcome",
group = "group",
covariates = character(0),
strata = group,
strategy = "strategy"
)Arguments
- subjid
The name of the "Subject ID" variable. A length 1 character vector.
- visit
The name of the "Visit" variable. A length 1 character vector.
- outcome
The name of the "Outcome" variable. A length 1 character vector.
- group
The name of the "Group" variable. A length 1 character vector.
- covariates
The name of any covariates to be used in the context of modeling. See details.
- strata
The name of the any stratification variable to be used in the context of bootstrap sampling. See details.
- strategy
The name of the "strategy" variable. A length 1 character vector.
Details
In both draws() and ancova() the covariates argument can be specified to indicate
which variables should be included in the imputation and analysis models respectively. If you wish
to include interaction terms these need to be manually specified i.e.
covariates = c("group*visit", "age*sex"). Please note that the use of the I() function to
inhibit the interpretation/conversion of objects is not supported.
Currently strata is only used by draws() in combination with method_condmean(type = "bootstrap")
and method_approxbayes() in order to allow for the specification of stratified bootstrap sampling.
By default strata is set equal to the value of group as it is assumed most users will want to
preserve the group size between samples. See draws() for more details.
Likewise, currently the strategy argument is only used by draws() to specify the name of the
strategy variable within the data_ice data.frame. See draws() for more details.
Examples
if (FALSE) { # \dontrun{
# Using CDISC variable names as an example
set_vars(
subjid = "usubjid",
visit = "avisit",
outcome = "aval",
group = "arm",
covariates = c("bwt", "bht", "arm * avisit"),
strategy = "strat"
)
} # }