Table 1

Definitions of quintiles

Variable	Unit	New variable	Name in text
SSS	Units (0–58)	SSS quintile	SSS quintile
ΔSSS	Units (3 months-acute)	ΔSSS quintile	Stroke recovery
EPO (acute)	mIU/mL	Acute EPO quintile	Acute EPO quintile
EPO (3 months)	mIU/mL	3-month EPO quintile	3-month EPO quintile
ΔEPO	mIU/mL (3 months-acute)	ΔEPO quintile	ΔEPO quintile

Variable	Information	q1	q2	q3	q4	q5	Interpretation
SSS	Ranges	1–36	37–50	51–54	55–57	58	Low values=severe stroke
	Severity	Severe	Major	Moderate	Minor	Mild
	n	117	126	120	109	128
ΔSSS	Ranges	−15 to −1	0	1–3	4–10	11–53	High values=more recovery
	n	15	148	114	146	123
EPO (acute)	Ranges	1.20–5.399	5.4–6.799	6.8–8.499	8.5–11.339	11.34–78.1	High values=more EPO
	n	95	94	103	102	98
EPO (3-month)	Ranges	1.6–6.099	6.1–7.699	7.7–9.599	9.6–12.699	12.7–57	High values=more EPO
	n	88	91	101	95	94
ΔEPO	Ranges	−71 to −1.60	−1.60 to 0.30	0.30–1.80	1.80–3.80	3.80–31.1	High values=increase of EPO
	n	87	91	92	87	92