Is there a simple way to assess whether COVID causes the symptoms in the study? Yes, just run the logistic regression with serology results as the only predictor. Fortunately for us the study includes this model – model 2.
This makes the assumption that people are equally likely to get infected with COVID regardless of health. What evidence is there for this assumption?
This makes the assumption that people are equally likely to get infected with COVID regardless of health. What evidence is there for this assumption?
Yes, this is a good point, I suspect most long COVID studies probably have the same flaw