Table 3. Effectiveness of nirsevimab against hospitalisation in infants by the screening method and test-negative design, three regions in Spain, October 2023–January 2024 (n = 166 admissions).

Method	RSV-LRTI (n = 95)		Negative RSV-LRTI (n = 71)
	(1−OR) x 100	95% CI	(1−OR) x 100	95% CI
Screening
Murcia	86.9	77.1 to 92.9	27.5		−47.3 to 66.2
Valencia	69.3	36.4 to 86.2	19.6		−180.8 to 82.3
Valladolid	97.0	87.7 to 99.6	NA
Pooled data	84.4	76.8 to 90.0	32.4		−27.5 to 63.4a
Test-negative design
Pooled data	70.2	38.3 to 88.5a	NA

CI: credible interval; LRTI: lower respiratory tract infection; NA: not available; OR: odds ratio; RSV: respiratory syncytial virus.

^a Only data from Murcia and Valencia were considered because there were no negative RSV-LRTI in Valladolid.