Table 3:

Adjusted model estimates of risk factors for intensive care unit admission for patients admitted to hospital with multisystem inflammatory syndrome in children^*

Variable	Absolute risk, % (95% CI)	Risk difference, % (95% CI)	Relative risk (95% CI)
Age, yr
0–5	18.4 (11.6 to 25.2)	–	–
6–12	43.6 (34.4 to 52.8)	25.2 (13.6 to 36.9)	2.37 (1.34 to 3.40)
13–18	46.2 (28.2 to 64.1)	27.7 (8.3 to 47.2)	2.51 (1.14 to 3.88)
Sex
Male	28.0 (21.3 to 34.8)	–	–
Female	35.6 (27.7 to 43.5)	7.6 (−2.9 to 18.1)	1.27 (0.85 to 1.69)
Country
Canada	34.7 (28.5 to 40.9)	–	–
Costa Rica	9.2 (1.0 to 17.4)	−25.5(−36.0 to −15.0)	0.26 (0.03 to 0.51)
Iran	58.7 (28.5 to 40.9)	24.0 (2.3 to 50.9)	1.69 (0.95 to 2.43)
Initial leukocyte count, × 10⁹/L^†
< 5	29.2 (14.6 to 43.9)	−1.1 (−17.2 to 15.0)	0.96 (0.44 to 1.49)
5–15	30.3 (24.1 to 36.6)	–	–
> 15	33.2 (20.2 to 46.2)	2.9 (−11.8 to 17.5)	1.10 (0.60 to 1.59)
Initial platelet count, × 10⁹/L^†
< 150	33.8 (23.6 to 44.0)	2.9 (−9.4 to 15.2)	1.09 (0.69 to 1.50)
≥ 150	30.9 (24.8 to 37.1)	–	–
Initial ferritin, μg/L^†
≤ 500	26.6 (20.9 to 32.5)	–	–
> 500	45.1 (33.8 to 56.4)	18.4 (5.6 to 31.3)	1.69 (1.12 to 2.26)
Gastrointestinal involvement	30.4 (25.2 to 35.6)	−11.7 (−30.3 to 6.9)	0.72 (0.39 to 1.05)
Mucocutaneous involvement	32.6 (27.0 to 38.1)	7.4 (−6.8 to 21.5)	1.29 (0.59 to 1.99)
Admission period
Mar. 1–Nov. 1, 2020	24.9 (16.8 to 33.0)	–	–
Nov. 1, 2020–Mar. 7, 2021	37.2 (28.9 to 45.6)	12.3 (−0.3 to 25.0)	1.50 (0.86 to 2.13)

Note: CI = confidence interval.
↵* Models are adjusted for sex, age, country, presence of comorbidity, coinfection, confirmed case status, treatment and admission time. Average marginal effects are presented with adjusted risk differences from multivariable logistic regressions.
↵† Number of observations differing from complete data set of 232, leukocytes: 4 missing; platelets: 2 missing; ferritin: 7 missing.