Table 4.

Validation of the influenza risk score: severe in-hospital complication by index score categories

Risk group (points)	No. with SIHC/no. at risk	Percentage (95 % CI)a	Odds ratio (95 % CI)
Low risk (0–2)	4/211	1.9 (0.1–3.7)	Ref.
Intermediate risk (3–4)	30/291	10.3 (6.8–13.8)	6 (2.1–17.1)
High risk (>4)	24/81	29.6 (19.7–39.5)	21.8 (7.3–65.3)
AUC			0.74

AUC, area under the receiver operating characteristic curve; CI, confidence interval; Ref., reference group

The low-risk group was considered as the reference group

^a p < 0.001 for the Cochran–Armitage test for trend