While clinical efforts have focused on promoting patient self-management, with some success, work in Psychology on behaviour change has had little influence on clinical practice. In this project, the team wish to evaluate the potential for a novel intervention from the behaviour change literature, self-affirmation, to promote improved fluid control among non-adherent patients. The intervention works by promoting a patient's sense-of-self (self-affirmation), which has been shown to modify the patient's acceptance of health-risk information, their self-efficacy, their intention to change, and subsequently their behaviour.