Table 2.

Mapping of drugs and drug classes in the OMOP reference set to ATC

Aggregation	Drugs (ATC5)		Drug classes (ATC4)
Outcome	Positive	Negative	Positive	Negative
Acute kidney injury	23	59	19	68
Acute liver injury	79	33	68	43
Acute myocardial infarction	33	61	18	72
GI bleed	24	62	19	73
Total	159	215	124	256

Positive and negative controls mapped to drugs and drug classes in ATC for the four adverse event outcomes in the OMOP reference set