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Trial concepts implemented across registers

Source: R/ctrdata-trial-concepts.R
ctrdata-trial-concepts.Rd

ctrdata includes (since version 1.21.0) functions that implement selected trial concepts. Concepts of clinical trials, such as their start or status of recruitment, require to analyse several fields against various pre-defined values. The structure and value sets of fields differ between all ctrdata-registers. In this situation, the implemented trial concepts simplify and accelerate a user's analysis workflow and also increase analysis consistency.

Details

The implementation of trial concepts in ctrdata has not been validated with any formal approach, but has been checked for plausibility and against expectations. The implementation is based on current understanding, on public data models and on scientific papers, as relevant. As with other R functions, call help("f.startDate") or print its implementation code by entering the name of the function as command, e.g. f.startDate. Please raise an issue here to ask about or improve a trial concept.

The following trial concepts can be used by referencing their name when calling dbGetFieldsIntoDf (parameter calculate). Concepts will continue to be refined and added; last updated 2025-03-09.

  • f.controlType (factor) which type of internal or concurrent control is used in the trial? ("none", "no-treatment", "placebo", "active", "placebo+active" or "other")

  • f.isMedIntervTrial (logical) is the trial interventional and does it have one or more medicines (drugs or biological) as investigational (experimental) intervention? (irrespective of status of authorisation and of study design)

  • f.isUniqueTrial (logical) is the trial record unique in the data frame of trial, based on the default parameters of dbFindIdsUniqueTrials?

  • f.likelyPlatformTrial (logical) is the trial possibly a (research) platform trial, and what are related trials? (based on trial title, f.numTestArmsSubstances, number of periods)

  • f.numSites (integer) how many sites does the trial have?

  • f.numTestArmsSubstances (integer) how many arms or groups have medicines that are investigational? (cannot be calculated for ISRCTN or for phase 1 trials)

  • f.primaryEndpointDescription (list of character) string containing protocol definition, details and time frames, concatenated with " == "

  • f.primaryEndpointResults (columns of number, character, integer) returning the statistical testing p value and method as well as the number of subjects included in the test, each in one new column, for the first primary endpoint only

  • f.resultsDate (date) the planned or achieved date of results availability

  • f.startDate (date) the planned, authorised or documented date of start of recruitment

  • f.sampleSize (integer) the achieved (or planned) number of subjects or participants recruited

  • f.sponsorType (factor) a type or class of main or lead sponsor that is simplified to "not for profit", "for profit" or "other"

  • f.statusRecruitment (factor) a status that is simplified to "ongoing" (includes temporarily halted), "completed", "ended early" (includes terminated or ended prematurely) and "other" (includes planned, stopped, withdrawn)

  • f.trialObjectives (string) identifies with letters those objectives that could be identified by text fragments, e.g. "E S PD D", with "E" (efficacy), "S" (safety), "D" (dose-finding)

  • f.trialPhase (ordered factor) the phase(s) of medicine development with which a trial is associated

  • f.trialPopulation (columns of factor, string and string) age groups (e.g., "P" for paediatric participants, "A" for adults, "E" for older than 65 years, or "P+A"), inclusion and exclusion criteria texts

Author

Ralf Herold ralf.herold@mailbox.org