Table 2.

Association of Illness Severity as Measured by PRISM III-12

Variables	Unadjusted		Multivariable
	β (95% CI)	p a	β (95% CI)	p
Age (ref = 2wk to <1yr)		0.002		0.008
1yr to <3yr	1.9 (1.1, 2.7)	<0.001	1.1 (0.3, 1.8)	0.004
3yr to <6yr	2.1 (0.9, 3.4)	<0.001	1.0 (−0.4, 2.3)	0.15
6yr to <18yr	4.4 (3.3, 5.6)	<0.001	2.8 (1.6, 4.0)	<0.001
Female gender (ref = male)	0.7 (0.0, 1.3)	0.07	0.2 (−0.5, 0.9)	0.57
Raceb (ref = White)		0.37		0.42
Black/African American	0.1 (−0.9, 1.0)	0.85	−0.1 (−0.9, 0.7)	0.79
Multiracial	0.4 (−1.4, 2.1)	0.67	0.6 (−1.1, 2.3)	0.47
Other	1.0 (0.1, 2.1)	0.07	0.8 (−0.1, 1.6)	0.07
Ethnicity (ref = non-Hispanic)	−0.8 (−1.7, 0.1)	0.10	−0.3 (−1.1, 0.5)	0.49
Primary diagnosis (ref = bronchiolitis)		0.002		0.007
Pneumonia	2.4 (1.4, 3.4)	<0.001	1.1 (0.0, 2.3)	0.04
Acute respiratory failure related to sepsis	8.5 (7.5, 9.6)	<0.001	7.1 (6.0, 8.2)	<0.001
Asthma or reactive airway disease	4.4 (3.1, 5.7)	<0.001	2.8 (1.4, 4.1)	<0.001
Aspiration pneumonia	4.3 (3.4, 5.3)	<0.001	2.9 (1.5, 4.3)	<0.001
Other	3.8 (2.6, 5.1)	<0.001	2.6 (1.2, 4.1)	<0.001
Income quartilec (ref = Low)		0.29		0.31
Low Middle	1.0 (0.0, 2.0)	0.05	0.9 (−0.1, 1.9)	0.08
High Middle	0.6 (−0.4, 1.6)	0.26	0.3 (−0.7, 1.3)	0.55
High	0.8 (0.0, 1.6)	0.06	0.1 (−0.5, 0.8)	0.69

PRISM III-12 = Pediatric Risk of Mortality score from first twelve hours in the PICU; CI = Confidence Interval.

Higher PRISM scores are associated with greater illness severity.

^aVariables significant at p <0.20 in unadjusted analyses were included in the multivariable analysis.

^bRace and ethnicity were included in the multivariable analysis to control for potential confounding with income.

^cIncome quartile was included in the multivariable analysis because it is the predictor variable of interest.