Table 3.

Overlap of distinct drug-HOI pairs at the drug ingredient level after mapping drugs to RxNorm and HOIs to SNOMED-CT

Literature (MEDLINE and CTD) vs spontaneous reporting (n = 3 049 743)	Product labeling (US and EU) vs spontaneous reporting (n = 2 702 577)	Literature (MEDLINE and CTD) vs product labeling (US and EU) (n = 566 379)	All three (n = 3 057 406)
119 293 (3.9%)	87 279 (3.2%)	14 838 (2.6%)	14 295 (0.5%)

The counts and percentages shown contrast the sum of the union (shown in the heading) and intersection of the distinct drug-HOI pairs from both sources mentioned. CTD: Comparative Toxicogenomics Database, EU: European Union, US: United States