Define Expanded Endpoint Specifications

Takes a dataset and an endpoint group specification, and it defines the expanded endpoint specifications. It creates metadata and filter strings for each endpoint group, which are used to subset the data accordingly. The function ensures that each endpoint group has the necessary information for further analysis.

Usage

define_expanded_ep(
  x,
  group_by,
  forced_group_levels = NULL,
  col_prefix = "endpoint_group"
)

Arguments

x

A data.table containing the data associated with the endpoints.

group_by

A list specifying the grouping for endpoints, where each element corresponds to a variable used for grouping endpoints and contains the levels for that grouping variable.

forced_group_levels

data.table (optional). Table with group levels that must be included in the expansion, regardless of group_by.

col_prefix

A prefix used to create the names of the metadata and filter columns in the output data.table. Defaults to "endpoint_group".

Value

A data.table with additional columns for metadata and filter conditions for each endpoint group. If the endpoint group is empty or consists only of NA values, the function returns NA.

Examples

library(data.table)
library(pharmaverseadam)

# Load sample data and add INDEX_ column
adcm <- as.data.table(pharmaverseadam::adcm)
adcm <- adcm[!is.na(CMCLAS)][1:50]  # Subset for brevity

# Define grouping: expand endpoint by therapeutic class
group_by <- list(CMCLAS = unique(adcm$CMCLAS))

# Generate expanded endpoint specifications
expanded <- define_expanded_ep(x = adcm, group_by = group_by)

# View structure: each row = one group level
expanded
#>    endpoint_group_metadata                             endpoint_group_filter
#>                     <list>                                            <char>
#> 1:               <list[1]> CMCLAS == "SYSTEMIC HORMONAL PREPARATIONS, EXCL."
#> 2:               <list[1]>                               CMCLAS == "UNCODED"
# Note: endpoint_group_metadata contains the group values
# endpoint_group_filter contains the filter string (e.g., 'CMCLAS == "NERVOUS SYSTEM"')