Table 1. Classification results.

	Positive cases					Negative cases
	Level 1	Level 2	Level 2 updated	Level 3	Level 3 updated	Insufficientevidence	Not a case	No evidence
ABC tool	101	221	N/A	7	N/A	488	2844	2373
Ontology with negation	98	223	223	8	8	3	3078	2622
Ontology without negation	98	178	223	4	8	3	3078	2622

The first row are the results of running the ABC tool online, as described in [19]. The second row is the initial ontology-based classification, using the same rules and with the addition of the negation for information non present in the reports. The last row is the ontology-based classification without the addition of the negation. Level 1, 2 and 3 columns represent the existing Brighton classification categories. Level 2 updated and Level 3 updated represent the category as they should have been encoded based on communication with the Brighton collaboration.