Is there any more documentation on the scoring system? As I understand it, the weights are just the percentage of COVID+ patients that had each symptom. Fever

Is there any more documentation on the scoring system? As I understand it, the weights are just the percentage of COVID+ patients that had each symptom. Fever gets 90.5 points because between 83 and 98% of pts had a fever and (83+98)/2 = 90.5. The thresholds are back-calculated from recommendations: A 60 year old with a fever and dry cough should see a doctor. Using the point system above, that's 212.9 points, so...that's where the line is drawn. This feels very adhoc to me, even though the (fractional!) point system makes it seem rigorous.