For those of you interested in using geographical differences in prevalence rates to try to get a greater understanding of PD, the paper by Pedro-Cuesta et al. is a must. It does for Spain what the paper by Willis does for the US.

Highlights:
- north bad, south good;
- identifies hot-spots.

"Spatial distribution of Parkinson's disease mortality in Spain, 1989-1998, as a guide for focused aetiological research or health-care intervention"
Jesús de Pedro-Cuesta, Eduard Rodríguez-Farré and Gonzalo Lopez-Abente
BMC Public Health, vol 9, Dec 2009.
http://www.biomedcentral.com/1471-2458/9/445

John