A Norwegian team looking into Long Covid ME/CFS formulated a quite good (but still somewhat flawed) questionnaire for quantifying functional disability that Pos

A Norwegian team looking into Long Covid ME/CFS formulated a quite good (but still somewhat flawed) questionnaire for quantifying functional disability that Post Exertional Mailaise (PEM) causes. Its called Funcap and there are two forms, 27 and 55 which are the number of questions. There is a publicly available SPA for this https://raffbenato.github.io/funcap55/ https://raffbenato.github.io/funcap55/ which will give you a good idea of the level of debilitation someone scoring 1 is dealing with. Funcap maps fairly well to the mild,moderate, severe and very severe descriptions that have been historically used and its fairly precise and improvements of 0.5 are very measurable. Its not popular yet but it should be its probably the best functionality questionnaire. In regards to linguistics there is a real issue with people who have never had a sensation understanding someone else describing it. ME/CFS is 4 symptoms and a few other groupings of them under the Canadian Consensus criteria but a lot of focus is put on fatigue and PEM. But the fatigue is not something someone who doesn't have the disease could understand. Its not tiredness like not sleeping enough, its somewhat more like the worst flu you ever had and made you want to stay in bed (which most people have not experienced) but its still underplaying the muscle weakness and lack of stamina and general feel of unwellness that encompasses this fatigue, its like all the cells in the body have no energy. There is simply no way to express this and have someone understand how debilitating that is and the consequences for breaching capacity, which make ME sufferers worse sometimes permanently. We just don't have the words or really the understanding because while many biological issues have been found nothing has yet been accepted as a biomarker of the condition.