Time trends and geographical variation in Parkinson's disease in Scotland.

Parkinson's disease is a common and disabling condition which principally affects the elderly. The time and space distribution of Parkinson's disease has been examined to determine if it provides clues as to aetiology and factors affecting its distribution. Previous studies have used mortality data, data from epidemiological studies, and prescribing information particularly with regard to the use of levodopa. These studies have looked within countries and between countries.