Funding, protocol development and statistical planning

Adequate resourcing and study planning help make sure participation changes can be well managed.

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Click ‘Read More’, below, to see a summary of the recommendations in this section.

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Research grant applications:

  • Consider how to ensure there is adequate resource to support all study follow-up activity, including for participants whose participation changes during their time on study, and those who ‘complete’ all aspects of participation.

Protocol development:

  • Protocols should retain the standard confirmation that participants have the right to withdraw their consent at any time.
  • Protocol content should be written with an understanding that participation changes can take many forms. Use language to convey this complexity.
  • All members of the study team can make important contributions to the protocol. For agreeing content about participation changes, there may be particularly important roles for statisticians and patient contributors.
  • Consider presenting content about broad sorts of participation change in different sections.
  • Consider referencing the PeRSEVERE principles and related guidance in the protocol, if these guide your study’s approaches.
  • Consider using the protocol to emphasise some of the positions given in the PeRSEVERE principles, about how participation changes should be managed in the study.
  • The protocol should explain what needs to happen when a participant says they want to stop or reduce their participation in the study.
  • The protocol should include instructions for study staff in case they lose contact with participants.
  • The protocol should be clear about any data collection that needs to continue in all cases.
  • Options for reduced or alternative follow-up schedules or methods should be referenced, with instructions for how and when to broach them with participants.
  • The protocol should contain any definitions of study-specific participation changes that are anticipated.
  • The protocol could include guidance about what should happen if a participant wants to increase their level of involvement after having previously reduced it (especially if this is expected to happen relatively frequently, for any reason).
  • Participating study sites might be encouraged to contact the clinical trials unit/research organisation to discuss the best action to take if any particularly complex or challenging situations arise.


Statistical analysis plans (SAPs):

  • Given the breadth of existing guidance around content of SAPs, we have not given detailed recommendations within the PeRSEVERE guidance.
  • However, we suggest that, as with other study documents, the language and terminology used in SAPs reflects the complexity of participation changes.
  • If it has been agreed that participants who want to stop taking part can continue to contribute with less commitment via alternative follow-up schedules or methods, then the SAP could cover any implications for how the study outcome data will be analysed (i.e. if some data was collected in different ways).