Defining impact

Defining impact

This page provides examples of the value and impact of consumer involvement

Involvement and Impact

It can be difficult to measure impact. This may be because consumer involvement is a complex social process making it challenging to pinpoint the impact of individual contributions (Crocker et al 2017). In addition, it is likely that consumer involvement carried out in the same way across different studies will not achieve the same impacts because many internal factors could influence the outcome.

At the individual trial level, it may not always be possible (or helpful) to consider consumer involvement as ‘an intervention’ that can be always be measured.  Consumer involvement may generate a range of impacts. Some will be more amenable to evaluation than others. This is likely to be because consumer involvement is highly context dependent. Researchers and consumers come with their own knowledge (whether from a textbook and/or from experience), share their expertise and experience with one another and through mutual learning, reach decisions about what research to do and how best to do it (Staley et al 2019). 


To confirm the value of this partnership, researchers/research organisations should work with consumers to agree on what will constitute a successful outcome and reflect on whether those outcomes have been met (see evaluation webpages).

Evidence of Impact

Evidence of the impact of consumer involvement is easier to demonstrate across studies.  A recent systematic review looking at the impact of involvement on recruitment, found that the involvement of people with lived experience of the condition under study was significantly associated with improved recruitment (Crocker et al 2018). In another study, researchers analysed 374 studies registered with the UK’s Mental Health Research Network; looking at the level of consumer involvement and its impact on recruitment. Studies with the highest levels of consumer involvement were 4.12 times more likely to achieve target recruitment (defined as reaching at least 90% of the target) than studies with the lowest levels (Ennis et al 2013).

A report released by The Economist Intelligence Unit and commissioned by Parexel, confirmed that trials with patient-centric designs; that is, trials that work with consumers to address the potential practical barriers to study participation, were nearly 20% more likely to be launched compared to trials that do employ patient-centric designs. The analysis also indicated that patient-centric trials took less time to recruit; on average, 4 months to enrol 100 patients compared to the average of 7 months for non-patient-centric trials.

Assessing the Impact of Consumer Involvement in Research


Measuring the Impact of Patient-Engaged Research: How a Methods Workshop Identified Critical Outcomes of Research Engagement (Dillon et al 2017)


Further Reading

  • Crocker, J et al. Is It Worth It? Patient and Public Views on the Impact of Their Involvement in Health Research and Its Assessment: a UK‐based Qualitative Interview Study. Health Expectations 20.3 (2017): 519–528
  • Staley K, Barron D. Learning as an outcome of involvement in research: what are the implications for practice, reporting and evaluation? Res Involv Engagem. (2019)
  • Brett, J et al. Mapping the impact of patient and public involvement on health and social care research: a systematic review. Health Expect. 2014;17(5):637–50.
  • Edelman, N et al. Evaluation of Public Involvement in Research: Time for a Major Re-Think? Journal of Health Services Research & Policy 21.3 (2016): 209–211.
  • Wright, D et al. Critical Appraisal Guidelines for Assessing the Quality and Impact of User Involvement in Research. Health Expectations 13.4 (2010): 359–368.
  • Crocker, J et al. Impact of Patient and Public Involvement on Enrolment and Retention in Clinical Trials: Systematic Review and Meta-Analysis. BMJ 28 Nov. (2018)
  • Ennis, L. et al. Impact of patient involvement in mental health research: longitudinal study. British Journal of Psychiatry (Sept 2013)
  • The Innovation Imperative: The Future of Drug Development, The Economist Intelligence Unit (2018)
  • Dillon, EC et al. Measuring the Impact of Patient-Engaged Research: How a Methods Workshop Identified Critical Outcomes of Research Engagement. JPCRR. (2017); 4: 237–246.
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