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The research process is often described as a ‘cycle’ or ‘pathway’. The research cycle model below, describes PPI at eight stages. The reality is more complex, but these models are a helpful starting point for PPI contributors to understand how research projects work, and where they as contributors fit into the research.

There is a clear expectation from the NIHR and other major funders that involvement should happen throughout the research pathway and that it will be evidenced in monitoring reports and research outcomes. Depending on the research project, every stage of the research pathway can potentially benefit from PPI. The project may need more PPI input at various stages work done in one stage can be used in another part of the pathway. Case studies from researchers, show PPI in practice across the pathway. PPI is also an iterative process, influencing the research work, and changing its outcomes and impacts. 

The same PPI contributors do not need to be included at every stage, some may be more suited or interested in specific stages. PPI is best done where it is meaningful, and this may not be the same extent at every stage. It needs to be done where it can make a difference otherwise it appears tokenistic. Be prepared to explain how this decision was made to funders.

Key messages from current researchers are:

  • Be creative and pragmatic
  • Flexibility is important too
  • It is not always possible to insist on an established process
  • Every study will be different
  • There is no one way to do PPI

“It wasn’t a case of ‘us’ versus ‘them’. We all worked together; clinicians, academics, our industry partners (Qbtech) and PPI. That was the real success of the trial.” (Source: Lead Researcher – Aqua Study)


 The research cycle model



The PPI research cycle model