derive_var_bcvacritxfl: Adds 'CRITx'/'CRITxFL' pairs to BCVA dataset

In admiralophtha: ADaM in R Asset Library - Ophthalmology

Adds CRITx/CRITxFL pairs to BCVA dataset

Description

The derive_var_bcvacritxfl() function has been deprecated in favor of admiral::derive_vars_crit_flag() - please see the criterion flag section of the ADBCVA vignette for more details.

Adds a criterion variables CRITx and their corresponding flags CRITxFL to a dataset containing BCVA records

Usage

derive_var_bcvacritxfl(
  dataset,
  crit_var,
  bcva_ranges = NULL,
  bcva_uplims = NULL,
  bcva_lowlims = NULL,
  additional_text = "",
  critxfl_index = NULL
)

Arguments

dataset	Input dataset containing BCVA data (usually ADBCVA). Permitted values a dataset, i.e., a data.frame or tibble Default value none
crit_var	Variable with respect to which CRITx/CRITxFL are derived (usually CHG or AVAL). Permitted values an unquoted symbol, e.g., AVAL Default value none
bcva_ranges	List of numeric vectors. For each vector c(a,b) in bcva_ranges, a pair of variables CRITx, CRITxFL is created with the condition: ⁠a <= crit_var <= b⁠. If criterion flags of that type are not required, then leave as NULL. Permitted values a list containing one or more numeric vectors, each of length two. E.g. ⁠list(c(1, 2), c(3, 4)⁠ Default value NULL
bcva_uplims	List containing one or more numeric elements. For each element a in bcva_uplims, a pair of variables CRITx, CRITxFL is created with the condition: crit_var <= a. If criterion flags of that type are not required, then leave as NULL. Permitted values a list containing one or more numeric scalars. E.g. list(2, -4) Default value NULL
bcva_lowlims	List containing one or more numeric elements. For each element b in bcva_lowlims, a pair of variables CRITx, CRITxFL is created with the condition: crit_var >= b. If criterion flags of that type are not required, then leave as NULL. Permitted values a list containing one or more numeric scalars. E.g. list(2, -4) Default value NULL
additional_text	string containing additional text to append to CRITx. Permitted values a character scalar, i.e., a character vector of length one Default value ""
critxfl_index	positive integer detailing the first value of x to use in CRITxFL. If not supplied, the function takes the first available value of x, counting up from x = 1. Permitted values a positive integer, e.g. 2 or 5 Default value NULL

Details

This function works by calling derive_var_bcvacritxfl() once for each of the elements in bcva_ranges, bcva_uplims and bcva_lowlims. NOTE: if crit_var is equal to NA, then the resulting criterion flag is also marked as NA.

Value

The input BCVA dataset with additional column pairsCRITx, CRITxFL.

Author(s)

Edoardo Mancini

See Also

Other deprecated: derive_var_bcvacritxfl_util()

Examples

library(tibble)
library(admiral)
library(admiraldev)

adbcva1 <- tribble(
  ~STUDYID, ~USUBJID, ~AVISIT, ~BASETYPE, ~PARAMCD, ~CHG,
  "XXX001", "P01", "BASELINE", "LAST", "SBCVA", 0,
  "XXX001", "P01", "WEEK 2", "LAST", "FBCVA", 2,
  "XXX001", "P02", "BASELINE", "LAST", "SBCVA", -13,
  "XXX001", "P02", "WEEK 2", "LAST", "FBCVA", 5,
  "XXX001", "P03", "BASELINE", "LAST", "SBCVA", NA,
  "XXX001", "P03", "WEEK 2", "LAST", "FBCVA", 17
)

derive_var_bcvacritxfl(
  dataset = adbcva1,
  crit_var = exprs(CHG),
  bcva_ranges = list(c(0, 5), c(-5, -1), c(10, 15)),
  bcva_uplims = list(5, 10),
  bcva_lowlims = list(8),
  additional_text = ""
)

adbcva2 <- tribble(
  ~STUDYID, ~USUBJID, ~AVISIT, ~BASETYPE, ~PARAMCD, ~AVAL, ~CHG,
  "XXX001", "P01", "BASELINE", "LAST", "SBCVA", 4, NA,
  "XXX001", "P01", "BASELINE", "LAST", "SBCVA", 6, NA,
  "XXX001", "P01", "AVERAGE BASELINE", "AVERAGE", "SBCVA", 5, NA,
  "XXX001", "P01", "WEEK 2", "LAST", "SBCVA", -3, NA,
  "XXX001", "P01", "WEEK 4", "LAST", "SBCVA", -10, NA,
  "XXX001", "P01", "WEEK 6", "LAST", "SBCVA", 12, NA,
  "XXX001", "P01", "WEEK 2", "AVERAGE", "SBCVA", -2, -7,
  "XXX001", "P01", "WEEK 4", "AVERAGE", "SBCVA", 6, 1,
  "XXX001", "P01", "WEEK 6", "AVERAGE", "SBCVA", 3, -2
)

restrict_derivation(
  adbcva2,
  derivation = derive_var_bcvacritxfl,
  args = params(
    crit_var = exprs(CHG),
    bcva_ranges = list(c(0, 5), c(-10, 0)),
    bcva_lowlims = list(5),
    additional_text = " (AVERAGE)"
  ),
  filter = PARAMCD %in% c("SBCVA", "FBCVA") & BASETYPE == "AVERAGE"
)

admiralophtha documentation built on Jan. 18, 2026, 9:07 a.m.