harmonize_survey_values: Harmonize values in surveys

In retroharmonize: Ex Post Survey Data Harmonization

Harmonize values in surveys

Description

Harmonize value codes and value labels across multiple surveys and combine them into a single data frame.

Usage

harmonize_survey_values(survey_list, .f, status_message = FALSE)

harmonize_waves(waves, .f, status_message = FALSE)

Arguments

survey_list	A list of surveys (data frames). In earlier versions this argument was called waves.
.f	A function applied to each labelled variable (class "retroharmonize_labelled_spss_survey"). The function must not change the length of the input vector.
status_message	Logical. If TRUE, prints the identifier of each survey as it is processed.
waves	A list of surveys. Deprecated.

Details

The function first aligns the structure of all surveys by ensuring that they contain the same set of variables. Missing variables are added and filled with appropriate missing values depending on their type.

Variables of class "retroharmonize_labelled_spss_survey" are then harmonized by applying a user-supplied function .f to each variable separately within each survey.

The harmonization function .f must return a vector of the same length as its input. If .f returns NULL, the original variable is kept unchanged.

Prior to version 0.2.0 this function was called harmonize_waves.

The earlier form harmonize_waves is deprecated. The function is currently called harmonize_waves.

Value

A data frame containing the row-wise combination of all surveys, with harmonized labelled variables and preserved attributes describing the original surveys.

See Also

Other harmonization functions: collect_val_labels(), crosswalk_surveys(), harmonize_na_values(), harmonize_values(), harmonize_var_names(), is.crosswalk_table(), label_normalize()

Examples

examples_dir <- system.file("examples", package = "retroharmonize")
survey_files <- dir(examples_dir, pattern = "\\.rds$", full.names = TRUE)

surveys <- read_surveys(
  survey_files,
  export_path = NULL
)

# Keep only supported variable types
surveys <- lapply(
  surveys,
  function(s) {
    s[, vapply(
      s,
      function(x) inherits(x, c(
        "retroharmonize_labelled_spss_survey",
        "numeric",
        "character",
        "Date"
      )),
      logical(1)
    )]
  }
)

# Identity harmonization (no-op)
harmonized <- harmonize_survey_values(
  survey_list = surveys,
  .f = function(x) x,
  status_message = FALSE
)

head(harmonized)

retroharmonize documentation built on Jan. 14, 2026, 9:08 a.m.