Integrating the Proposed Solution

Oct 13, 2025 by wbrum.org 92 views

Introduction

REDCapR is a powerful R package for interacting with REDCap databases. One of its key features is the ability to download reports from REDCap, which can be useful for data analysis and visualization. However, the current implementation of REDCapR's column type guessing mechanism has some limitations. In this article, we will discuss these limitations and propose a solution that utilizes the data dictionary/schema provided by REDCap.

Current Implementation

The current implementation of REDCapR's column type guessing mechanism is based on the following code snippet:

https://github.com/OuhscBbmc/REDCapR/blob/d8144a70900f9a299cbd34fde18a51177eee3130/R/redcap-report.R#L185-L191

This code snippet uses the httr package to send a POST request to the REDCap API with the required parameters. The response from the API is then parsed to extract the column types. However, this approach has some limitations. For example, it may not always accurately guess the column types, especially for complex data types such as matrices.

Proposed Solution

To improve the column type guessing mechanism, we can utilize the data dictionary/schema provided by REDCap. This dictionary contains information about the column types, which can be used to accurately determine the types of each column. We can use the following code snippet to retrieve the data dictionary/schema:

get_coltypes <- function(token, uri) {
  formData_dict <- list(token = token,
                          content = 'metadata',
                          format = 'csv',
                          returnFormat = 'json'
  )
  response_dict <- httr::POST(uri, body = formData_dict, encode = "form")
  dict_raw <- httr::content(response_dict, col_types = cols(.default = "c",
                                                   matrix_ranking = "-",
                                                   matrix_group_name = "-",
                                                   question_number = "-",
                                                   required_field = "-",
                                                   custom_alignment = "-")) |>
    mutate(
      coltype = case_when(
        field_type == "text" &
          text_validation_type_or_show_slider_number == "number" ~ "d",
        field_type == "text" &
          text_validation_number == "integer" ~ "i",
        field_type == "text" ~ "c",
        field_type == "calc" ~ "d",
        field_type %in% c("radio", "dropdown") ~ "i",
        field_type %in% c("checkbox", "truefalse", "yesno") ~ "l",
        TRUE ~ "c"
      ),
      field_name_overall = field_name
    )

  dict_raw |>
    filter(field_type == "checkbox") |>
    separate_longer_delim(select_choices_or_calculations, delim = " | ") |>
    separate_wider_delim(select_choices_or_calculations, delim = ", ",
                         names = c("choice_number", "choice_name")) |>
    mutate(field_name = sprintf("%s___%s", field_name, choice_number)) |>
    (\(x) bind_rows(dict_raw, x))()
}

This code snippet uses the httr package to send a POST request to the REDCap API with the required parameters. The response from the API is then parsed to extract the column types. The mutate function is used to create a new column called coltype that contains the accurate column types.

Integrating the Proposed Solution

To integrate the proposed solution into the existing code, we can use the following code snippet:

report_cols <-
  readr::read_csv(file = I(kernel$raw_text), col_types = cols(.default = "c")) |>
  colnames()
report_coltypes <- get_coltypes(token, redcap_uri) |>
  filter(field_name %in% report_cols) |>
  pull(coltype, field_name)
report_coltypes[c("redcap_repeat_instrument", "redcap_repeat_instance")] = "i"
ds <- readr::read_csv(file = I(kernel$raw_text), col_types  = report_coltypes)

This code snippet uses the get_coltypes function to retrieve the accurate column types from the data dictionary/schema. The filter function is used to filter the column types to only include the columns that are present in the report. The pull function is used to extract the column types from the data frame. Finally, the readr::read_csv function is used to read the report into a data frame with the accurate column types.

Conclusion

In conclusion, the current implementation of REDCapR's column type guessing mechanism has some limitations. To improve this mechanism, we can utilize the data dictionary/schema provided by REDCap. The proposed solution uses the httr package to send a POST request to the REDCap API with the required parameters. The response from the API is then parsed to extract the accurate column types. The get_coltypes function can be used to integrate this solution into the existing code. By using this solution, we can improve the accuracy of the column type guessing mechanism and provide more accurate results for data analysis and visualization.

Future Work

In the future, we can further improve the column type guessing mechanism by incorporating additional features such as:

Support for complex data types: The current implementation only supports simple data types such as integers and strings. We can extend this to support complex data types such as matrices and arrays.
Support for custom data types: The current implementation only supports standard data types such as integers and strings. We can extend this to support custom data types such as dates and times.
Improved accuracy: The current implementation uses a simple heuristic to guess the column types. We can improve this by using more advanced machine learning algorithms to improve the accuracy of the column type guessing mechanism.

Q: What is the current implementation of REDCapR's column type guessing mechanism?

A: The current implementation of REDCapR's column type guessing mechanism is based on the following code snippet:

https://github.com/OuhscBbmc/REDCapR/blob/d8144a70900f9a299cbd34fde18a51177eee3130/R/redcap-report.R#L185-L191

This code snippet uses the httr package to send a POST request to the REDCap API with the required parameters. The response from the API is then parsed to extract the column types.

Q: What are the limitations of the current implementation?

A: The current implementation has some limitations. For example, it may not always accurately guess the column types, especially for complex data types such as matrices.

Q: How can we improve the column type guessing mechanism?

A: We can improve the column type guessing mechanism by utilizing the data dictionary/schema provided by REDCap. This dictionary contains information about the column types, which can be used to accurately determine the types of each column.

Q: What is the proposed solution for improving the column type guessing mechanism?

A: The proposed solution uses the httr package to send a POST request to the REDCap API with the required parameters. The response from the API is then parsed to extract the accurate column types. The get_coltypes function can be used to integrate this solution into the existing code.

Q: How can we integrate the proposed solution into the existing code?

A: We can integrate the proposed solution into the existing code by using the following code snippet:

report_cols <-
  readr::read_csv(file = I(kernel$raw_text), col_types = cols(.default = "c")) |>
  colnames()
report_coltypes <- get_coltypes(token, redcap_uri) |>
  filter(field_name %in% report_cols) |>
  pull(coltype, field_name)
report_coltypes[c("redcap_repeat_instrument", "redcap_repeat_instance")] = "i"
ds <- readr::read_csv(file = I(kernel$raw_text), col_types  = report_coltypes)

Q: What are the benefits of using the proposed solution?

A: The proposed solution has several benefits, including:

Improved accuracy: The proposed solution uses the data dictionary/schema provided by REDCap to accurately determine the types of each column.
Reduced errors: The proposed solution reduces the likelihood of errors caused by incorrect column types.
Improved data analysis and visualization: The proposed solution provides more accurate results for data analysis and visualization.

Q: What are the future directions for improving the column type guessing mechanism?

A: Some future directions for improving the column type guessing mechanism include:

Support for complex data types: The current implementation only supports simple data types such as integers and strings. We can extend this to support complex data types such as matrices and arrays.
Support for custom data types: The current implementation only supports standard data types such as integers and strings. We can extend this to support custom data types such as dates and times.
Improved accuracy: The current implementation uses a simple heuristic to guess the column types. We can improve this by using more advanced machine learning algorithms to improve the accuracy of the column type guessing mechanism.

By incorporating these features, we can further improve the accuracy and reliability of the column type guessing mechanism and provide more accurate results for data analysis and visualization.