The PINE Study follows a large population-based cohort of individuals with and without Parkinson's disease and other forms of parkinsonism in Aberdeen, Scotland. The cohort was originally recruited for an incidence study, for which most participants consented to be followed up (94%). Each eligible participant who consented to follow up was age and sex matched with a patient from the same primary care practice or a register of elderly people who had taken part in a previous community-based screening project. Since its inception, PINE has sustained high retention and annual follow up.