derive_var_bcvacritxfl_util: Add 'CRITx'/'CRITxFL' pair to BCVA dataset
In admiralophtha: ADaM in R Asset Library - Ophthalmology

derive_var_bcvacritxfl_util

R Documentation

Add `CRITx`/`CRITxFL` pair to BCVA dataset

Description

The derive_var_bcvacritxfl_util() function has been superseded in favor of admiral::derive_vars_crit_flag().

Helper function for derive_var_bcvacritxfl() that adds a criterion variable CRITx and its corresponding flag CRITxFL to a dataset containing BCVA records

Usage

derive_var_bcvacritxfl_util(
  dataset,
  crit_var,
  critx_text,
  critxfl_cond,
  counter,
  bcva_range = NULL,
  bcva_uplim = NULL,
  bcva_lowlim = NULL
)

Arguments

`dataset`	Input dataset (usually ADBCVA).
`crit_var`	Variable with respect to which `CRITx`/`CRITxFL` are derived (usually `CHG` or `AVAL`).
`critx_text`	String containing the text for `CRITx` variable.
`critxfl_cond`	String containing R code detailing the criterion to be satisfied for `CRITxFL` variable to be equal to "Y".
`counter`	Integer detailing the value of x to use in `CRITxFL`.
`bcva_range`	Numeric vector of length two detailing lower and upper change in BCVA limits (`bcva_range` will be called in `critxfl_cond` if the criterion stipulates that change in BCVA lie inside some range).
`bcva_uplim`	Numeric value detailing highest change in BCVA limit (`bcva_uplim` will be called in `critxfl_cond` if the criterion stipulates that change in BCVA lie below some upper limit).
`bcva_lowlim`	Numeric value detailing lowest change in BCVA limit (`bcva_lowlim` will be called in `critxfl_cond` if the criterion stipulates that change in BCVA lie above some lower limit).

Details

The criterion for change in BCVA in CRITxFL can be of three types: (1) value lies within some range; ⁠a <= crit_var <= b⁠; (2) value is below some upper limit; crit_var <= a; (3) value is above some lower limit; b <= crit_var. For (1), bcva_range must be specified to this function; for (2), bcva_uplim; for (3) bcva_lowlim. It is necessary to supply at least one of these three arguments. NOTE: if crit_var is equal to NA, then the resulting criterion flag is also marked as NA.