REDCapR (development version)

New Features

• New redcap_instrument_repeating() function exports repeating instrument-event mappings for a project. (#585 & #589, @ezraporter)

Minor Enhancements

• New columns returned from the server to redcap_project_info_read() no longer throw a warning. (#587)
• redcap_file_repo_list_oneshot() function tests for the new dag and role columns (#593)
• redcap_write() now accommodates single-column data.frames. Previously only single-column tibbles were accommodated. (@brandonerose, #591 & #592)
• Update urls for REDCap Community (#596)
• Simplified token files for other people to test with (#594)

REDCapR 1.6.0 (released 2025-10-07)

This release is primarily small changes to comply with a CRAN check. One of the examples accidentally called an external/test server, which is against CRAN rules.

Minor Enhancements

• Avoid calling server in a CRAN example (#577)
• Add new multilevel model test project to the test suite (#578)

REDCapR 1.5.0 (released 2025-07-27)

This release is primarily small changes to comply with new CRAN checks

Minor Enhancements

• Avoid native pipes outside of essential package code (#572). (Essential package code has always used magrittr pipes to allow REDCapR to run on version of R before 4.1.0.)
• Avoid calling server in a CRAN example (#571)

REDCapR 1.4.0 (released 2025-01-11)

New Features

• redcap_file_repo_list_oneshot() export a list of files/folders from the file repository (requested by @agdamsbo, #549)

Minor Enhancements

• Vignettes are not run/evaluated on CRAN, to comply with it policies. (#561)
• Alt text for figures. (#550)

REDCapR 1.3.0 (released 2024-10-22)

Minor Enhancements

• Redirection layer for test suite allows you to plug in your own server (#539, #542, #544)
• Skip a test when checked on CRAN servers (but not on local or GitHub Action machines)

REDCapR 1.2.0 (released 2024-09-08)

Possibly Breaking Change

These changes could possibly break existing code --but it's very unlikely. We feel they will (directly and indirectly) improve the package considerably.

• redcap_read(), redcap_read_oneshot(), redcap_dag_read(), redcap_log_read(), and redcap_report() return a tibble instead of a data.frame. (#415)

  This should affect client code only if you expect a call like ds[, 3] to return a vector instead of a single-column data.frame/tibble. One solution is to upcast the tibble to a data.frame (with something like as.data.frame()). We recommend using an approach that works for both data.frames and tibbles, such as ds[[3]] or dplyr::pull(ds, "gender").

  For more information, read the short chapter in R for Data Science.

• The *_collapsed parameters are deprecated. When your want to limit on records/fields/forms/events, pass the vector of characters, not the scalar character separated by commas (which I think everyone does already). In other words use c("demographics", "blood_pressure") instead of "demographics,blood_pressure".

  Here are the relationships between the four pairs of variables:

  records_collapsed   <- collapse_vector(records  , records_collapsed)
  fields_collapsed    <- collapse_vector(fields   , fields_collapsed)
  forms_collapsed     <- collapse_vector(forms    , forms_collapsed)
  events_collapsed    <- collapse_vector(events   , events_collapsed)
  

  If someone is using the *_collapsed parameter, they can programmatically convert it to a vector like:

  field_names <- trimws(unlist(strsplit(field_names_collapsed, ",")))
  

• redcap_read() will automatically include the "plumbing" variables, even if they're not included the list of requested fields & forms. (#442). Specifically:

  • record_id (or it's customized name) will always be returned
  • redcap_event_name will be returned for longitudinal projects
  • redcap_repeat_instrument and redcap_repeat_instance will be returned for projects with repeating instruments

This will help extract forms from longitudinal & repeating projects.

• redcap_read() and redcap_read_oneshot() now return an empty dataset if no records are retrieved (such as no records meet the filter criteria). Currently a 0x0 tibble is returned, but that may change in the future. Until now an error was deliberately thrown. (#452)

• redcap_event_instruments() now by default returns mappings for all arms. The previous default was to return the mappings for only the first arm. To recreate the previous behavior use a call like REDCapR::redcap_event_instruments(uri, token_2, arms = "1"). (Suggested by @januz, #482)

• redcap_users_export() used to return a boolean for user_rights, but now it can be 0, 1, or 2. (#523)

New Features

• New redcap_metadata_coltypes() function. Inspects the fields types and validation text of each field to generate a suggested readr::col_types object that reflects the project's current data dictionary. The object then can be passed to the col_types parameter of redcap_read() or redcap_read_oneshot(). (Suggested and discussed with @pbchase, @nutterb, @skadauke, & others, #405 & #294)
• New redcap_log_read() function. Exports a project's log. (Thanks @joundso, #383, #320)
• New redcap_project_info_read() function. Exports a project's information, such as its language and production status. (Suggested by @skadauke, @timothytsai, @pbchase, #236, #410)
• New parameter blank_for_gray_form_status in the functions redcap_read(), redcap_read_oneshot(), and redcap_read_oneshot_eav(). (@greg-botwin, #386, #389)
• A httr::handle value is accepted by functions that contact the server. This will accommodate some institutions with unconventional environments. (Suggested by @brandonpotvin, #429)
• sanitized_token() now accepts an alternative regex pattern. (Suggested by @maeon & @michalkouril, #370)
• redcap_read_eav_oneshot() is an UNexported function that returns data in an EAV format (#437)
• redcap_metadata_read() now correctly subsets the forms (identified & corrected by @ezraporter, #431 & #445)
• New redcap_event_read() function. Exports metadata associated with a project's longitudinal events (@ezraporter, #457 & #460)

Minor Enhancements

• Better documentation for the server url (suggested by @sutzig #395)

• read_read_oneshot()'s parameter guess_max now allows floating point values to support readr::read_csv() ability to accept a Inf value. (Suggested by @eveyp, #392)

• pkgdown pages run & display the examples, but CRAN still doesn't run them. It's illegal to call external resources/APIs from CRAN computers --mostly because they are occasionally unavailable, so the code breaks. (#419)

• Renamed some functions to follow a consistent pattern. Old names will be soft-deprecated for a while before being removed. (#416)

  • redcap_download_file_oneshot() to redcap_file_download_oneshot()
  • redcap_file_upload_oneshot() to redcap_file_upload_oneshot()
  • redcap_download_instrument() to redcap_instrument_download()

• redcap_dag_read() has new data_access_group_id field (introduced maybe in 13.1.0) (#459)

• redcap_users_export() has new mycap_participants field (introduced maybe in 13.0.0) (#459)

• Accommodate older versions of REDCap that don't return project-level variable, like has_repeating_instruments_or_events, missing_data_codes, external_modules, bypass_branching_erase_field_prompt (@the-mad-statter, #465, #466)

• redcap_meta_coltypes() correctly determines data type for autonumber record_id fields. It suggests a character if the project has DAGs, and an integer if not. (@pwildenhain, #472)

• redcap_log_read() now returns a new column reflecting the affected record id value (ref #478)

• redcap_read() and redcap_read_oneshot() now remove "pseudofields" (e.g., redcap_event_name, redcap_repeat_instrument, & redcap_repeat_instance) from the fields parameter. Starting with REDCap v13.4.10, an error is thrown by the server. REDCap will return a message if a common pseudofield is requested explicitly by the user. (#477)

• redcap_event_instruments() now can return mappings for all arms, instead of one arm per call.(Suggested by @januz, #482)

• validate_for_write() contains a few more checks. (#485) The complete list is now:

  • validate_data_frame_inherits()
  • validate_field_names()
  • validate_record_id_name()
  • validate_uniqueness()
  • validate_repeat_instance()
  • validate_no_logical()

• redcap_read() checks the event parameter and throws an error if a value is not recognized, or the project is not longitudinal (#493)

• The regex in regex_named_captures() is forgiving if there's an unnecessary leading space (@BlairCooper, #495, #501)

• redcap_log_read() assumes all columns are character, except for timestamp (#525)

• redcap_file_download_oneshot() no longer asks for the unnecessary parameter for repeating_instrument (that the REDCap server ignores). (@BlairCooper, #506, #530)

• redcap_read() and redcap_read_oneshot() accommodate readr::read_csv()'s parameter of na. (Suggested by @rmtrane in #529)

REDCapR 1.1.0 (released 2022-08-10)

New Features

• New redcap_delete() function. It deletes a vector of records. (Thanks @joundso, #372, #373)
• New redcap_arm_export() function. It retrieves a list of REDCap project arms. (#375)
• redcap_read() and redcap_read_oneshot() accept a new locale parameter that specifies date, time, and number formats, like using a comma as the decimal separator. It is a readr::locale object. (#377, suggested by @joundso)
• New redcap_instruments() function exports a list of the data collection instruments for a project. (#381, @vcastro)
• New redcap_event_instruments() function exports the instrument-event mappings for a project (i.e., how the data collection instruments are designated for certain events in a longitudinal project). (#381, @vcastro)
• New redcap_dag_read() function returns the Data Access Groups for a project (#382, @joundso)
• New detection when REDCap has trouble with a large request and drops records. (#400 w/ @TimMonahan)

Minor Enhancements

• sanitize_token() now allows lowercase characters --in addition to uppercase characters & digits. (#347, @jmbarbone)
• redcap_metadata_read() now uses json (instead of csv) to transfer the dictionary between server & client. This accommodates super-wide dictionaries with 35k+ variables. The user shouldn't notice a difference, and still will receive a data.frame. (#335, @januz & @datalorax)
• Include a few more testthat::skip_on_cran() calls to comply with CRAN's "fail gracefully" policy. Similarly, skip remaining examples that depend on external resources. (#352)
• retrieve_credential_local() can now user username to identify the desired credential row (#364)
• redcap_read() and redcap_read_oneshot() gain the http_response_encoding parameter that's passed to httr::content(). The default value remains "UTF-8". (#354, @lrasmus)
• Accommodate single-character REDCap variable names (#367 & #368, @daynefiler)
• Modify redcap_users_export() (which calls REDCap's user export). The API dropped the data_export variable and added the forms_export variable. (#396)
• For redcap_read_oneshot_eav(): if the project isn't longitudinal, a dummy value for event_id is used internally (#396)
• For the testing server & projects, the http errors are a little different, so the testing code was adjusted (#396)
• Set httr::user_agent, following the advice of httr's vignette (#397)

Test Suite

• Added two more dictionaries that are super wide -5k & 35k variables (#335 & #360, @januz & @datalorax)
• Read, modify, & read projects with DAGs (#353, daniela.wolkersdorfer, #353)

REDCapR 1.0.0 (released 2021-07-21)

The package has been stable for years and should be reflected in the major version number.

Minor Enhancements

• When writing records to the server, the functions redcap_write() and redcap_write_oneshot() have a new parameter that converts R's logical/boolean columns to integers. This meshes well with T/F and Y/N items that are coded as 1/0 underneath. The default will be FALSE (ie, the integers are not converted by default), so it doesn't break existing code. (#305)
• When writing records to the server, the functions redcap_write() and redcap_write_oneshot() can toggle the ability to overwrite with blank/NA cells (suggested by @auricap, #315)
• The functions redcap_read_oneshot(), redcap_read(), & redcap_read_oneshot_eav() now support the parameters datetime_range_begin and datetime_range_end. The are passed to the REDCap parameters dateRangeBegin and dateRangeEnd, which restricts records returned, based on their last modified date in the server. (Thanks @pbchase, #321 & #323.)
• Better documentation about the export_survey_fields parameter in the functions redcap_read() & redcap_read_oneshot(). (Thanks @isaactpetersen, #333)
• New function redcap_report() export records that populate a REDCap report. (#326.)
• New vignette Typical REDCap Workflow for a Data Analyst developed to support a workshop for the 2021 R/Medicine Conference (#332, with @higgi13425, @kamclean, & Amanda Miller)
• New function create_credential_local() starts a well-formed csv file that can contain tokens. (#340, after conversations with @higgi13425 & @kamclean.)

Stability Features

• update for newer version of testthat -v3.0.0 (#312)
• update for newer version of readr 2.0.0 (#343)
• update for newer version of readr 1.4.0 (#313)
• update for newer version of REDCap on test server (#310)
• save expected datasets as files -instead of included in the actual test code (#308)

Corrections & Bug Fixes

• Accepts more than one config_option element. (Proposed by @BastienRance, #307)
• Fixed calculation of success value returned by redcap_read() and redcap_write() when the parameter continue_on_error is true. (Bug found by @llrs, #317)
• redcap_survey_link_export_oneshot() documentation corrected & improved (@jrob95, #526)

REDCapR 0.11.0 (Released 2020-04-20)

Breaking Changes (possible, but unlikely)

• kernel_api() defaults to "text/csv" and UTF-8 encoding. Formerly, the function would decide on the content-type and encoding. More details are below in the 'Stability Features' subsection.

• constant() no longer accepts simplify as an options. An integer vector is always returned. (#280)

New Features

• It's now possible to specify the exact col_types (a readr::cols object) that is passed to readr::read_csv() inside redcap_read_oneshot(). (#258)

• reader::type_convert() is used after all the batches are stacked on top of each other. This way, batches cannot have incompatible data types as they're combined. (#257; thanks @isaactpetersen #245) Consequently, the guess_max parameter in redcap_read() no longer serves a purpose, and has been soft-deprecated. (#267)

• redcap_metadata_write() writes to the project's metadata. (#274, @felixetorres)

• redcap_survey_link_export_oneshot() retrieves the URL to a specific record's survey (e.g., "https://redcap-dev-2.ouhsc.edu/redcap/surveys/?s=8KuzSLMHf6") (#293)

• convert_logical_to_integer is a new parameter for redcap_write() and redcap_write_oneshot(). If TRUE, all [base::logical] columns in ds are cast to an integer before uploading to REDCap. Boolean values are typically represented as 0/1 in REDCap radio buttons. Defaults to FALSE to maintain backwards compatibility. (#305)

Stability Features

• httr::content() (which is inside kernel_api()) now processes the returned value as "text/csv", by default. This should prevent strange characters from tricking the process as the internal variable raw_text is being formed. See the [httr::content()](https://httr.r-lib.org/reference/content.html) documentation for a list of possible values for the content_type` parameter. (Thanks to great debugging by @vortexing #269, @sybandrew #272, & @begavett, #290)

• Similarly, kernel_api() now has an encoding parameter, which defaults to "UTF-8". (#270)

Minor Enhancements

• check for bad field names passed to the read records functions (#288)

Corrections

• 'checkmate' package is now imported, not suggested (Thanks @dtenenba, #255).

• Allow more than one httr::config() parameter to be passed (Thanks @BastienRance, #307).

REDCapR 0.10.2 (Released 2019-09-22)

Minor New Features

• export survey time-stamps optionally (Issue #159)
• redcap_next_free_record_name(): API call for 'Generate Next Record Name', which returns the next available record ID (Issue #237)
• redcap_read() and redcap_read_oneshot() allow the user to specify if all variables should be returned with the character data type. The default is to allow readr::read_csv() to guess the data type. (#194)
• redcap_read_oneshot() allows use to specify how many rows should be considered when readr::read_csv() guesses the data type. (#194)
• redcap_read(), redcap_read_oneshot(), and redcap_read_oneshot_eav() always return Linux-style line endings (ie \n) instead of Windows style line endings (ie, \r\n) on all OSes. (#198)
• read_metadata() always returns character vectors for all variables. With readr 1.2.0, some column were returned differently than before. (#193)
• 'raw_or_label_headers' now supported (Thanks Hatem Hosny - hatemhosny, #183 & #203)
• 'export_checkbox_labels' now supported (#186)
• redcap_users_export() now included (#163)
• 'forms' now supported for redcap_read(), redcap_read_oneshot(), & redcap_read_oneshot_eav()(#206). It was already implemented for redcap_metadata_read().
• If no records are affected, a zero-length character vector is returned (instead of sometimes a zero-length numeric vector) (#212)
• New function (called constants()) easily exposes REDCap-specific constants. (#217)
• id_position allows user to specify if the record_id isn't in the first position (#207). However, we recommend that all REDCap projects keep this important variable first in the data dictionary.
• Link to new secure Zenodo DOI resolver (@katrinleinweber #191)
• parameters in redcap_read() and redcap_read_oneshot() are more consistent with the order in raw REDCap API. (#204)
• When the verbose parameter is NULL, then the value from getOption("verbose") is used. (#215)
• guess_max parameter provided in redcap_read() (no longer just redcap_read_oneshot()). Suggested by @isaactpetersen in #245.
• Documentation website constructed with pkgdown (#224).
• redcap_variables() now throws an error when passed a bad URI (commit e542155639bbb7).

Modified Internals

• All interaction with the REDCap server goes through the new kernal_api() function, which uses the 'httr' and 'curl' packages underneath. Until now, each function called those packages directly. (#213)
• When converting REDCap's CSV to R's data.frame, readr::read_csv() is used instead of utils::read.csv() (Issue #127).
• updated to readr 1.2.0 (#200). This changed how some data variables were assigned a data types.
• uses odbc package to retrieve credentials from the token server. Remove RODBC and RODBCext (#188). Thanks to @krlmlr for error checking advice in https://stackoverflow.com/a/50419403/1082435.
• data.table::rbindlist() replaced by dplyr::bind_rows()
• the checkmate package inspects most function parameters now (instead of testit::assert() and base:stop() ) (#190 & #208).
• collapse_vector() is refactored and tested (#209)
• remove dependency on pkgload package (#218)
• Update Markdown syntax to new formatting problems (#253)

Deprecated Features

• retrieve_token_mssql(), because retrieve_credential_mssql() is more general and more useful.

REDCapR 0.9.8 (Released 2017-05-18)

New Features

• Enumerate the exported variables. with redcap_variables().
• Experimental EAV export in redcap_read_oneshot_eav(), which can be accessed with a triple colon (ie, REDCapR::redcap_read_oneshot_eav()).

Bug Fixes

• Adapted to new 2.4 version of curl (see #154)

REDCapR 0.9.7 (Released 2017-09-09)

New Features

• Support for filtering logic in redcap_read() and redcap_read_oneshot() (PR #126)
• New functions retrieve_credential_mssql() and retrieve_credential_local(). These transition from storing & retrieving just the token (ie, retrieve_token_mssql()) to storing & retrieving more information. retrieve_credential_local() facilitates a standard way of storing tokens locally, which should make it easier to follow practices of keeping it off the repository.
• Using parameterized queries with the RODBCext package. (Thanks @nutterb in issues #115 & #116.)
• Remove line breaks from token (Thanks @haozhu233 in issues #103 & #104)

Minor Updates

• When combining batches into a single data.frame, data.table::rbindlist() is used. This should prevent errors with the first batch's data type (for a column) isn't compatible with a later batch. For instance, this occurs when the first batch has only integers for record_id, but a subsequent batch has values like aa-test-aa. The variable for the combined dataset should be a character. (Issue #128 & https://stackoverflow.com/questions/39377370/bind-rows-of-different-data-types; Thanks @arunsrinivasan)
• Uses the dplyr package instead of plyr. This shouldn't affect callers, because immediately before returning the data, REDCapR::redcap_read() coerces the tibble::tibble (which was formerly called dplyr::tbl_df) back to a vanilla data.frame with as.data.frame().
• A few more instances of validating input parameters to read functions. (Issue #8).

REDCapR 0.9.3 (Released 2015-08-25)

Minor Updates

• The retrieve-token() tests now account for the (OS X) builds where the RODBC package isn't available.

REDCapR 0.9.0 (Released 2015-08-14)

New Features

• Adapted for version 1.0.0 of httr (which is now based on the curl package, instead of RCurl).

Minor Updates

• Uses requireNamespace() instead of require().
• By default, uses the SSL cert files used by httr, which by default, uses those packaged with R.
• Added warning if it appears readcap_read() is being used without 'Full Data Set' export privileges. The problem involves the record IDs are hashed.
• Reconnected code that reads only the id_position in the first stage of batching. The metadata needed to be read before that, after the updates for REDCap Version 6.0.x.
• retrieve_token_mssql() uses regexes to validate parameters

REDCapR 0.7-1 (Released 2014-12-17)

New Features

• Updated for Version 6.0.x of REDCap (which introduced a lot of improvements to API behavior).

REDCapR 0.6 (Released 2014-11-03)

New Features

• The config_options in the httr package are exposed to the REDCapR user. See issues #55 & #58; thanks to @rparrish and @nutterb for their contributions (https://github.com/OuhscBbmc/REDCapR/issues/55 & https://github.com/OuhscBbmc/REDCapR/issues/58).

REDCapR 0.5 (Released 2014-10-19)

New Features

• redcap_metadata_read() are tested and public.

Minor Updates

• Test suite now uses testthat::skip_on_cran() before any call involving OUHSC's REDCap server.
• Vignette example of subsetting, conditioned on a second variable's value.

REDCapR 0.4-28 (Released 2014-09-20)

New Features

• redcap_write() and redcap_write_oneshot() are now tested and public.
• redcap_write() and redcap_write_oneshot() are now tested and public.
• redcap_download_file_oneshot() function contributed by John Aponte (@johnaponte; Pull request #35)
• redcap_upload_file_oneshot() function contributed by @johnaponte (Pull request #34)
• Users can specify if an operation should continue after an error occurs on a batch read or write. Regardless of their choice, more debugging output is written to the console if verbose==TRUE. Follows advice of @johnaponte, Benjamin Nutter (@nutterb), and Rollie Parrish (@rparrish). Closes #43.

Breaking Changes

• The records_collapsed default empty value is now an empty string (i.e., "") instead of NULL. This applies when records_collapsed is either a parameter, or a returned value.

Updates

• By default, the SSL certs come from the httr package. However, REDCapR will continue to maintain a copy in case httr's version on CRAN gets out of date.
• The tests are split into two collections: one that's run by the CRAN checks, and the other run manually. Thanks, Gabor Csardi. Any test with a dependency outside the package code (especially the REDCap test projects) is run manually so changes to the test databases won't affect the success of building the previous version on CRAN.
• Corrected typo in redcap_download_file_oneshot() documentation, thanks to Andrew Peters (@ARPeters #45).

REDCapR 0.3 (Released 2014-09-01)

New Features

• Relies on the httr package, which provides benefits like the status code message can be captured (eg, 200-OK, 403-Forbidden, 404-NotFound). See https://cran.r-project.org/package=httr.

Updates

• Renamed the former status_message to outcome_message. This is because the message associated with http code returned is conventionally called the 'status messages' (eg, OK, Forbidden, Not Found).
• If an operation is successful, the raw_text value (which was formerly called raw_csv) is returned as an empty string to save RAM. It's not really necessary with httr's status message exposed.

Bug Fixes

• Correct batch reads with longitudinal schema #27

REDCapR 0.2 (Released 2014-07-02)

New Features

• Added redcap_column_sanitize() function to address non-ASCII characters
• Added redcap_write() (as an internal function).
• The redcap_project() object reduces repeatedly passing parameters like the server URL, the user token, and the SSL cert location.

Updates

• New Mozilla SSL Certification Bundles released on cURL (released 2013-12-05)
• Renamed redcap_read_batch() to redcap_read(). These changes reflect our suggestion that reads should typically be batched.
• Renamed redcap_read() to redcap_read_oneshot()
• Renamed redcap_write() to redcap_write_oneshot() (which is an internal function).
• Small renames to parameters

REDCapR 0.1 (Released 2014-01-14)

New Features

• Introduces redcap_read() and redcap_read_batch() with documentation
• SSL verify peer by default, using cert file included in package
• Initial submission to GitHub

Enhancements

• redcap_read() takes parameter for raw_or_label (Thanks Rollie Parrish #3)
• redcap_read() takes parameter for export_data_access_groups thanks to Rollie Parrish (@rparrish #4)

---

GitHub Commits and Releases

• For a detailed change log, please see https://github.com/OuhscBbmc/REDCapR/commits/main.
• For a list of the major releases, please see https://github.com/OuhscBbmc/REDCapR/releases.