as_mmrm_df function

Creates a "MMRM" ready dataset

Converts a design matrix + key variables into a common format In particular this function does the following:

• Renames all covariates as V1, V2, etc to avoid issues of special characters in variable names

• Ensures all key variables are of the right type

• Inserts the outcome, visit and subjid variables into the data.frame

  naming them as outcome, visit and subjid

• If provided will also insert the group variable into the data.frame named as group

as_mmrm_df(designmat, outcome, visit, subjid, group = NULL)

Arguments

• designmat: a data.frame or matrix containing the covariates to use in the MMRM model. Dummy variables must already be expanded out, i.e. via stats::model.matrix(). Cannot contain any missing values
• outcome: a numeric vector. The outcome value to be regressed on in the MMRM model.
• visit: a character / factor vector. Indicates which visit the outcome value occurred on.
• subjid: a character / factor vector. The subject identifier used to link separate visits that belong to the same subject.
• group: a character / factor vector. Indicates which treatment group the patient belongs to.