WPSS assigns points for three variables and sums them (range 0–6):

Variable	Category	Score
WHO MDS subtype	RCUD, RARS or MDS with isolated del(5q)	0
	RCMD or RCMD-RS	1
	RAEB-1	2
	RAEB-2	3
Cytogenetic risk	Good (normal, -Y, del(5q), del(20q))	0
	Intermediate (all other cytogenetic abnormalities)	1
	Poor (complex ≥3 abnormalities or chromosome 7 anomaly)	2
Transfusion requirement	No regular RBC transfusions	0
Transfusion requirement	Regular RBC transfusions (≥1 unit every 8 weeks for ≥4 months)	1

Total WPSS score = sum of component scores (0–6).

WPSS (WHO classification-based Prognostic Scoring System) for Myelodysplastic Syndrome