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Table 4 Advantages and challenges of generic and comparison-specific case report forms

From: Changing platforms without stopping the train: experiences of data management and data management systems when adapting platform protocols by adding and closing comparisons

CRF type Generic Comparison-specific
Advantages • Efficient if data requirements are similar across comparisons
• Data are captured consistently across comparisons
• Capacity to still make sections specific by arm, comparison, sites, patient sub-group, etc.
• CRF changes need to be made on only one set of CRFs, reducing time taken for development/amendments
• Generally fewer CRFs overall
• Efficient if data requirements are substantially different across comparisons
• Only data required for a single comparison is captured
• Not likely to become as complex as generic CRFs. May therefore be easier for site staff to use.
• Each CRF is easier to maintain for comparison-specific changes
• Not all changes across life of the trial must be included, only those during the lifespan of the CRF
Challenges • Adding comparisons/questions.
- Increasing length and complexity as additional data requirements are added
- Question numbering can become unwieldy if new questions are needed within the existing CRF
- Unanticipated changes may require existing CRF to be redeveloped or a new CRF to be developeda
- Shared control arm participants may be affected by new comparisons requiring conditional questions/sections to be addedb
• Less flexibility in collecting data
- Must ensure CRFs can be relevant for all comparisons
• Changes external to the trial may be more likely to impact generic CRFsc
- Universal coding lists changing the names or values of items on the listd
- Changes in standard of care
• Generic changes will need to be made across specific CRFs separately, increasing maintenance time and risk of errors.
• More CRFs in total
- Can take longer to train site staff on each individual CRF if they are different from each other
- Version control/CRF tracking. Multiple similar versions with differing version numbers. Data management staff must be more careful to ensure correct version is used.
• If a shared control arm is being used, CRFs for this arm must still capture data required for multiple comparisons whilst ensuring this does not introduce bias; additional questions may lead to events being more likely to be reported or introduce other biases. Some questions may need to be added to all comparison-specific CRFs to avoid this.
  1. CRF Case report form
  2. aSee practical examples from STAMPEDE CRF amendments
  3. bEasier to accomplish in electronic data capture with conditional formatting in the study database
  4. cCould still be a challenge for comparison-specific CRFs
  5. dE.g. Common Terminology Criteria for Adverse Events (CTCAE) update V3.0 to V4.0