There is a dearth of evidence for the assumed beneficial effects of involving patients and the public in health-research decisions (S. Petit-Zeman and L. Locock Nature 501, 160–161; 2013). This is just one example of the general difficulty of measuring the impact of setting health-research priorities.

These priorities are decided by researchers and policy-makers to stimulate urgent research (see, for example, go.nature.com/pxealf). The guidelines for evaluating such priority-setting processes (R. F. Viergever et al. Health Res. Policy Sys. 8, 36; 2010) need to be extended to cover impact measurement and analysis.

Impact measurements might include: evaluating general changes, such as in the attitudes of researchers and policy-makers; monitoring the research that is undertaken in line with the established priorities (for example, by looking at conducted clinical trials or published articles: see J-A. Røttingen et al. Lancet http://doi.org/n4c; 2013); and assessing the impact of that research on factors such as health or socio-economic status (see R. Banzi et al. Health Res. Policy Sys. 9, 26; 2011).

Analysis of these impact measurements could be useful for building evidence to justify and improve prioritization in health research and to monitor progress for informing future priority-setting.