Table 3B.

Final Model for Risk Factors Associated with Stage II Hospital Length of Stay Excluding 13 Subjects Not Discharged Between Norwood and Stage II Procedures. (N=331, generalized R²=0.24).

Variable	Hazard ratio (95% CI)	P	Reliability
Site		<.001	98%
Log of Norwood Length of stay in days	1.56 (1.25, 1.96)	<.001	79%
Non-elective reason for timing of stage II	1.88 (1.42, 2.50)	<.001	89%
Associated clinical diagnosis with stage II: Branch PA stenosis present	1.60 (1.22, 2.10)	<.001	81%
Pre-stage II Echo: RV fractional area change (range 0 to 1)*	0.91 (0.85, 0.98) Per 0.05 increase	0.017	54%

^*28 subjects had missing RV fractional area change on pre-stage II Echo.