The contributions of patients are valuable, providing alternative views to researchers - they are a formal mechanism which legitimises research and in some cases are key to making the research work. The public/patients/service users have direct experience and knowledge of phenomena that clinicians/academics don't have. This privileged knowledge means that:

• They are able to make judgments based on their understanding of their condition and may provide different perspectives
• They can have different aspirations and thoughts about health outcomes, that healthcare professionals and researchers may not have considered
• They can ensure that topic areas and priorities are pertinent to their experiences, needs and preferences
• They can ensure that researchers measure outcomes that are important to them

The reported benefits of involvement include:

• Improved study recruitment
• More patient focused outcomes
• Improved relevance and reliability of results

Patient and Public Involvement in research is increasingly becoming a condition of funding