Have been thinking about this a fair bit recently. One of the most common forms of advocacy with this illness is stressing how debilitating it is, but also how common, citing a greater prevelance than say, MS. However, it’s difficult to know how accurate our numbers really are with this. I believe the range of numbers you get for patients in the US is between 800,000 and 2.5 million - a huge difference. While in the UK, the figure of 250,000 seems to have been used for at least 20 years, possibly more. In their latest note on the update of the guidelines, NICE cite a figure of 190,000. I suppose my general question is - how does one accurately estimate the prevelance of an illness, and also what people think about the figures we usually use? To me, they’re not as robust as they could be, but I’m not sure how to improve that.