Introduction: Many researchers find it difficult to involve consumers: it may require overcoming considerable cultural barriers. First, why should they do it? Second, where may suitably qualified consumers be found? Third, how should consumers be involved? This paper offers some suggestions as to how such problems may be tackled.

Discussion: Why? Because the whole point of medical research is to benefit patients: they are important stakeholders. From the beginning, the Cochrane Collaboration has sought to involve consumers in its work. Consumers can contribute personal knowledge of how it feels to experience a disease or a treatment. A researcher may see only a very small part of a specialist topic: the detail, not the broad canvas. Consumer input should improve the quality of review by constantly focusing the minds of researchers on the relevance and accessibility of their work. Involving consumers may also help researchers to use plain language and avoid jargon.
Where may consumers be found? and how can we be sure that they are suitably qualified? It is unwise for doctors and researchers to rely on their favourite patients for feedback. If local consumers are difficult to find, consult the international Consumer network. So as to minimise the risk of bias, consult more than one consumer, and ask people who are accountable to a wide constituency (for instance, a local or national support organisation), also try to find people who have undergone appropriate training (for instance, Project LEAD).
How to involve consumers? Treat consumers as colleagues, in exactly the same way as you would your fellow-researchers. Treat them with respect; listen to what they say; incorporate their comments unless you have very strong reasons not to (in which case tell them: this is what courtesy demands); thank them (they will be glad of feedback since they often work in isolation). Budget for their expenses, And regard the exercise as one that will improve your review: it should be undertaken with commitment and enthusiasm.