Culture change in infection control: applying psychological principles to improve hand hygiene.

Hand hygiene occurs at the intersection of habit and culture. Psychological and social principles, including operant conditioning and peer pressure of conforming social norms, facilitate behavior change. Participatory leadership and level hierarchies are needed for sustainable patient safety culture. Application of these principles progressively and significantly improved hand hygiene compared with the hospital aggregate control. Changes to hand hygiene auditing and response processes demonstrate ability to improve and sustain adherence rates within a clinical microsystem.