Expand Reduced Imputed Data to Full Dataset

Reconstructs the full imputed dataset from a reduced form by merging imputed values back with the original observed data. This is the inverse operation of reduce_imputed_data().

Usage

expand_imputed_data(reduced_data, original_data, vars)

Arguments

reduced_data

A data.frame containing only the imputed values, as returned by reduce_imputed_data().

original_data

A data.frame containing the original dataset before imputation, with missing values in the outcome column.

vars

A vars object as created by rbmi::set_vars().

Value

A data.frame containing the full imputed dataset with one complete dataset per IMPID value. The structure matches the output of get_imputed_data().

Details

For each imputation (identified by IMPID), this function:

1. Starts with the original data (observed values)

2. Replaces missing outcome values with the corresponding imputed values

3. Stacks all imputations together

See also

reduce_imputed_data() to create the reduced dataset, get_imputed_data() to extract imputed data from an rbmi imputation object.

Examples

library(rbmi)
library(dplyr)

# Example with package data
data("ADMI", package = "rbmiUtils")
data("ADEFF", package = "rbmiUtils")

# Prepare original data to match ADMI structure
original <- ADEFF |>
  mutate(
    TRT = TRT01P,
    USUBJID = as.character(USUBJID)
  )

vars <- set_vars(
  subjid = "USUBJID",
  visit = "AVISIT",
  group = "TRT",
  outcome = "CHG"
)

# Reduce and then expand
reduced <- reduce_imputed_data(ADMI, original, vars)
expanded <- expand_imputed_data(reduced, original, vars)

# Verify expansion
cat("Original ADMI rows:", nrow(ADMI), "\n")
#> Original ADMI rows: 100000 
cat("Expanded rows:", nrow(expanded), "\n")
#> Expanded rows: 100000