Table 6.

Wald statistic for independent variables of final models by outcome and population

	Upper quartile length of stay		30 day non-elective readmission		In-hospital mortality
	Elective	Non-elective	Elective	Non-elective	Elective	Non-elective
Age	31.1	31.4	0.0	0.4	46.4	747.2
Sex	18.7	0.2	6.9	77.6	9.5	85.2
Country	162.0	244.2	31.1	102.1	12.8	137.8
Admission history	-	-	225.9	1888.4	-	-
Dr Foster global frailty score	1020.7	2579.9	2.0	3.8	62.7	318.2
Elixhauser score	1727.5	4075.1	420.4	848.4	973.9	4842.1