Data has been collected annually since 2004/05. A new GMS Contract was introduced in April 2004 and a fundamental funding stream called the Quality and Outcomes Framework (QOF) was introduced at that time. QOF is a reward framework of indicators designed to remunerate general practices for providing good quality care to their patients. An important feature of QOF is the maintenance of registers which allow prevalence of a number of long-term conditions to be calculated. Register counts and prevalence per 1,000 GP registered population are published. Where registers are age-specific, prevalence per 1,000 age-specific population are also published.