Table 4.

Overview of the original intervention study search filter's performance in PubMed and Embase in the validation reference gold standard

	PubMed
	Relevant records in a retrospective search (= gold standard, a+b): 73	Irrelevant records in a retrospective search (c+d): 10,512
Records retrieved with search filter (a+c): 3,957	True positives (a): 66	False positives (c): 3,891
Records not retrieved with search filter: 6,628	False negatives (b): 7	True negatives (d): 6,621
	Embase
	Relevant records in a retrospective search (= gold standard, a+b): 70	Irrelevant records in a retrospective search: 16,586
Records retrieved with search filter (a+c): 7,403	True positives (a): 63	False positives (c): 7,340
Records not retrieved with search filter: 9,253	False negatives (b): 7	True negatives (d): 9,246