This commentary addresses these omissions: What is the impact of all this focus on measuring impact? How is the language of impact shaping the debate about, and the practice of, public involvement in health research? And how have shifting conceptualisations of public involvement in health research shaped, and been shaped by, the way we think about and measure impact? We argue that the focus on impact risks distorting how public involvement in health research is conceptualised and practised, blinding us to possible negative impacts.
