Table 1.

NCC MERP index and Nesbit score for categorizing medication errors [20, 21]

Category NCC MERP		Content	Nesbit probability score
No error	A	Circumstances that have the capacity to cause error	0 = zero	Information only
Error, no patient harm	B	An error occurred, but the error did not reach the patient
	C	An error occurred that reached the patient, but did not cause patient harm	0.01 = very low	Problem orders
	D	An error occurred that reached the patient and required monitoring to confirm that it resulted in no harm to patient and/or required intervention to preclude harm	0.1 = low	Some harm is expected, but poorly clinical relevant
Error, patient harm	E	An error occurred that may have contributed to, or resulted in temporary harm to the patient and required intervention	0.4 = medium	Harm is expected, clinically relevant
	F	An error occurred that may have contributed to, or resulted in temporary harm to the patient and required initial, or prolonged hospitalization	0.6 = high	Harm is expected, life threatening
	G	An error occurred that may have contributed to, or resulted in permanent harm
	H	An error occurred that required intervention necessary to sustain life
Error, death	I	An error occurred that may have contributed to, or resulted in the patient’s death