CRASH generates separate haematologic and non-haematologic toxicity subscores plus a combined score. Each predictor contributes 0-2 points.

Domain	Predictor	Criteria	Points
Haematologic	Chemotherapy regimen risk (MAX2/Chemotox)	MAX2 0-0.44 / 0.45-0.57 / >0.57	0 / 1 / 2
Haematologic	Diastolic blood pressure	≤72 mmHg / >72 mmHg	0 / 1
Haematologic	IADL score	26-29 / <26	0 / 1
Haematologic	LDH	0-459 U/L / >459 U/L	0 / 2
Non-haematologic	Chemotherapy regimen risk (MAX2/Chemotox)	MAX2 0-0.44 / 0.45-0.57 / >0.57	0 / 1 / 2
Non-haematologic	ECOG performance status	0 / 1-2 / 3-4	0 / 1 / 2
Non-haematologic	MMSE	30 / <30	0 / 2
Non-haematologic	MNA	28-30 / <28	0 / 2

Haematologic and non-haematologic subscores are the sums of their respective item points, including Chemotox in both. Combined CRASH score = haematologic subscore + non-haematologic subscore - Chemotox points, so regimen risk is counted once.

Band	Haematologic subscore	Non-haematologic subscore	Combined score	Approx severe toxicity in derivation cohort
Low	0-1	0-2	0-3	H about 7%, NH about 33%, combined about 50%
Intermediate-low	2-3	3-4	4-6	H about 23%, NH about 46%, combined about 58%
Intermediate-high	4-5	5-6	7-9	H about 54%, NH about 67%, combined about 77%
High	>5	>6	>9	H about 100%, NH about 93%, combined about 79%

Chemotherapy Risk Assessment Scale for High-Age Patients (CRASH) Score