Elin Strømme Nilsen, Hilde Tinderholdt Myrhaug, Marit Johansen, Sandy Oliver, Andrew D Oxman

The importance of consumer involvement in health care is widely recognised. Consumers can be involved in developing healthcare policy and research, clinical practice guidelines and patient information material, through consultations to elicit their views or through collaborative processes. Consultations can be single events, or repeated events, large or small scale. They can involve individuals or groups of consumers to allow debate; the groups may be convened especially for the consultation or be established consumer organisations. They can be organised in different forums and through different media. We anticipated finding few comparative evaluations that reliably evaluated the effects of consumer involvement.