Table 4. Procedural effect on LOS in gallstone-related pancreatitis.

				% Change in LOS when ERCP was done at any time on the admission
	Univariate OR (95 %)	S.E.	P value	Multivariate OR (95 %CI)	S.E.	P value
Conservative Management	Ref		NA	Ref		NA
ERCP	0.27 (0.27 0.28)	.004	< 0.001	0.29 (0.28 0.30)	.004	< 0.001
Age	0.01 (0.01 0.01)	.000	< 0.001	0.00 (0.00 0.00)	.000	0.004
Severe pancreatitis	0.69 (0.68 0.70)	.006	< 0.001	0.55 (0.54 0.56)	.006	< 0.001
Elixhauser Index	0.10 (0.10 0.11)	.000	< 0.001	0.07 (0.07 0.07)	.005	< 0.001

LOS, length of stay; ERCP, endoscopic retrograde cholangiopancreatography; S.E., standard error.