British claim they have a simple method of dividing Covid-19 patients into 4 risk groups:

https://medicalxpress.com/news/2020-09-discovery-covid-groups-treatment.html

Sample quote

Some of the data used to identify which group a person falls into—and, therefore, their risk of dying—included age, sex, the number of pre-existing conditions, respiratory rate on admission, and the results of two blood tests.

One in every hundred patients in the low-risk group was found to be at risk of dying.
It was 10 in a hundred patients in the intermediate-risk group,
31 in a hundred in the high-risk group and
62 in a hundred in the very high-risk group.

End quote