Sokal Score is a prognostic score done at diagnosis to
determine the patient as low-risk, intermediate-risk and
high-risk based on diagnosis markers of the spleen size,
platelet count, age and blast count.

Here is a link to calculate SOKAL SCORE from diagnosis
blood picture and characteristics:

http://www.roc.se/Sokal.asp

The Gleevec IRIS trials found that low-risk Sokal score
patients had a higher incidence of complete cytogenetic
remissions compared to high-risk patients.