Table 2.

Calculation of relative risk

Study	Calculation	Risk definition by calculation
Sokal et al. 19847	Exp 0.0116 × (age − 43.4) + 0.0345 × (spleen − 7.51) + 0.188 × [(platelet count ÷ 700)2 − 0.563] + 0.0887 × (blast cells − 2.10)	Low risk: <0.8
		Intermediate risk: 0.8-1.2
		High risk: >1.2
Euro	0.666 when age ≥50 y + (0.042 × spleen) + 1.0956 when platelet count >1500 × 109L + (0.0584 × blast cells) + 0.20399 when basophils >3% + (0.0413 × eosinophils) × 100	Low risk: ≤780
Hasford et al. 19988		Intermediate risk: 781-1480
		High risk: >1480
EUTOS	Spleen × 4 + basophils × 7	Low risk: ≤87
Hasford et al. 20119		High risk: >87

Age is given in years. Spleen is given in centimeters below the costal margin (maximum distance). Blast cells, eosinophils, and basophils are given in percent of peripheral blood differential. All values must be collected before any treatment. To calculate Sokal and Euro risk score, go to http://www.leukemia-net.org/content/leukemias/cml/cml_score/index_eng.html. To calculate EUTOS risk score, go to http://www.leukemia-net.org/content/leukemias/cml/eutos_score/index_eng.html.