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Translate REDCap Logic to R Logic

Source: R/rd_rlogic.R
rd_rlogic.Rd

[Stable]

Converts a REDCap logic expression into R-compatible logic. Processes one logic expression (logic) for one target variable (var) at a time. Supports common REDCap operators (and, or, =, <, >, etc.) and handles event-specific logic in longitudinal projects. Logic involving smart variables or repeated instruments may require manual review.

Usage

rd_rlogic(
  project = NULL,
  data = NULL,
  dic = NULL,
  event_form = NULL,
  logic,
  var
)

Arguments

project

A list containing the REDCap data, dictionary, and event mapping (expected redcap_data() output). Overrides data, dic, and event_form.

data

A data.frame or tibble with the REDCap dataset.

dic

A data.frame with the REDCap dictionary.

event_form

Only applicable for longitudinal projects (presence of events). Event-to-form mapping for longitudinal projects.

logic

A single REDCap logic string (e.g., "if([exc_1]='1' or [inc_1]='0', 1, 0)").

var

A single string specifying the target variable the logic applies to.

Value

A list with:

rlogic

The translated R-compatible logic as a string.

eval

The evaluation of the translated logic on the provided dataset, filtered by event if applicable.

Details

  • Translates REDCap operators and functions into R equivalents:

    • = → ==, <> → !=, and → &, or → |.

    • Converts functions like if(), rounddown(), datediff(), sum() to R equivalents.

  • Handles date transformations and empty strings ('') → NA.

  • Adjusts logic for longitudinal data using event_form if provided.

  • Evaluates the translated R logic against the dataset and returns the results.

  • Logic with repeated instruments, smart variables, or multiple events per variable may require manual inspection.

Examples

# Translate a single REDCap logic expression for one variable
covican |>
  rd_rlogic(
    logic = "if([exc_1]='1' or [inc_1]='0' or [inc_2]='0' or [inc_3]='0', 1, 0)",
    var = "screening_fail_crit"
  )
#> $rlogic
#> [1] "ifelse(data$exc_1=='1' | data$inc_1=='0' | data$inc_2=='0' | data$inc_3=='0', 1, 0)"
#> 
#> $eval
#>   [1]  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0
#>  [26] NA  0 NA  0 NA  0 NA  0 NA  0  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0
#>  [51] NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0  0  0  0 NA  0  0  0  0  0  0  0
#>  [76]  0  0  0  0  0  0  0  0  0  0  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0
#> [101] NA  0 NA  0 NA  0 NA  0 NA  1  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  1
#> [126]  0 NA  0 NA  0 NA  0 NA  0 NA  0  0 NA  0 NA  0 NA  0  0  0 NA  0 NA  0 NA
#> [151]  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA
#> [176]  0 NA  0  0 NA  0 NA  0 NA  0  0 NA  0 NA  0  0 NA  0 NA  0 NA  0 NA  0 NA
#> [201]  0 NA  0 NA  0 NA  0 NA  0  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA
#> [226]  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0
#> [251] NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA
#> [276]  0 NA  0 NA  0 NA  0 NA  0 NA  1  0 NA  1  0 NA  0 NA  0  0 NA  0  0 NA  0
#> [301] NA  0  0 NA  0  0 NA  0 NA  0  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0
#> [326] NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA  0 NA
#>