Table 2.

Allocated causality and clinical significance classifications

	Clinical significance classification*
Causality classification	Category A	Category B	Category C	Total
Definite	33	10	11	54
Probable	10	9	12	31
Possible	20	8	14	42
Total	63	27	37	127

^*A drug-related problem that results in the patient being admitted to hospital: for up to 24 h (Category A); for 24–48 h (Category B); for a period greater than 48 h and/or requires admission to an intensive care unit (Category C).