Table 1.

Summary of specificity results for the Elecsys Anti-SARS-CoV-2 immunoassay in blood donor and routine diagnostic samples

Group	Sample cohort	Samples tested, n	Reactive, n	Non-reactive, n	Specificity, % (95% CI)
Groups A and B		9575	14	9561	99.85 (99.75–99.92)
Group A (blood donors)	Austria (Innsbruck), influenza seasona	1048	5	1043	99.52 (98.89–99.84)
	Germany (Hagen), no seasonal selection	2625	2	2623	99.92 (99.73–99.99)
	Switzerland (Bern), no seasonal selection	3041	5	3036	99.84 (99.62–99.95)
	Switzerland (Bern), outside influenza season	2003	2	2001	99.90 (99.64–99.99)
	Switzerland (Bern), influenza season	1038	3	1035	99.71 (99.16–99.94)
	All	6714	12	6702	99.82 (99.69–99.91)
Group B (routine diagnostic testing)	Germany (Augsburg), routine diagnostic	400	0	400	100.00 (99.08–100.00)
	Germany (Augsburg), pregnancy	1498	2	1496	99.87 (99.52–99.98)
	Germany (Heidelberg), pregnancy	758	0	758	100.00 (99.51–100.00)
	Germany (Augsburg and Heidelberg), pregnancy	2256	2	2254	99.91 (99.68–99.99)
	Germany (Heidelberg), paediatrics	205	0	205	100.00 (98.22–100.00)
	All	2861	2	2859	99.93 (99.75–99.99)

CI confidence interval, SARS-CoV-2 severe acute respiratory syndrome coronavirus 2

^aSamples from Innsbruck were analysed at Augsburg