Sorry, no epidemiological studies. Must be a first in modern medical history. No wonder we are so angry. There are some studies that I have heard of to look at the overall numbers of CFS patients in the population. These studies are often vitiated by the use of overinclusive definitions of the disease and so get no-where. I do not know of any study that looks at how the numbers with this disease have grown over time in the population. There have only been small studies of epidemic outbreaks made by the local doctors concerned at the time. There dont appear to be any looking longitudinally - to see how the disease progresses and what disease associations there are. I was initially very surprised when the WPI associated ME with leukemia and autism as there seem to be more autistic type disorders in families with ME. In Britain it had always been treated as a completely benign disease! There have been no biobanks established to preserve tissue samples for research. Those that are being established now are being done by patient charities. For a common disease that has been around since the fifties this is astounding, dont you think? These problems with research are longstanding complaints in the ME community but however often the poor quality of the research is pointed out, better scientific studies have never been done.