Table 2.

Univariate analysis to assess predictors of timely procedural intervention

	First Intervention within 48 hrs	First Intervention after 48 hrs	p Value
	Pt demographics
Mean pt age (SD)	54.9 (17.3)	57.7 (18.1)	<0.001
No. male (%)	3,062 (45.9)	1,789 (49.6)	<0.001
No. race (%):
Caucasian	4,575 (68.4)	2,297 (63.6)	<0.001
African-American	428 (6.4)	284 (7.9)
Hispanic	1,231 (18.4)	788 (21.8)
Asian	190 (2.8)	79 (2.2)
Other/unknown	265 (4.0)	164 (4.5)
No. primary insurance   provider (%):
Public insurance	3,063 (45.8)	2,085 (57.0)	<0.001
Private insurance	2,621 (39.2)	1,041 (28.8)
Self-pay/uninsured	1,005 (15.0)	513 (14.2)
No. weekend admission (%)	1,672 (25.0)	1,138 (31.5)	<0.001
	Medical comorbidities
No. diabetes mellitus,   type II (%)	1,339 (20.0)	853 (23.6)	<0.001
No. hypertension (%)	2,630 (39.3)	1,655 (45.8)	<0.001
No. congestive heart   failure (%)	231 (3.5)	217 (6.0)	<0.001
No. coronary artery   disease (%)	802 (12.0)	573 (15.9)	<0.001
No. chronic renal   insufficiency (%)	816 (12.2)	636 (17.6)	<0.001
No. chronic lung disease (%)	747 (11.2)	477 (13.2)	0.002
Mean Charlson comorbidity   index (SD)	0.9 (1.3)	1.2 (1.6)	<0.001
	Presenting diagnoses
No. stone location (%):
Kidney	1,008 (15.1)	705 (19.5)	<0.001
Ureter	5,681 (84.9)	2,907 (80.5)
No. urinary tract infection (%)	4,432 (66.3)	2,382 (66.0)	0.8
No. hydronephrosis (%)	5,292 (79.1)	2,923 (80.9)	0.03
No. sepsis (%)	238 (3.6)	98 (2.7)	0.02
No. acute renal   insufficiency (%)	2,679 (40.1)	1,553 (43.0)	0.004
	Primary intervention
No. urological   intervention (%)	6,628 (99.1)	3,547 (98.2)	<0.001
No. interventional radiology   intervention (%)	61 (0.9)	65 (1.8)
	Outcomes
No. new onset acute renal   insufficiency (%)	69 (1.0)	64 (1.8)	0.001
No. new onset sepsis (%)	58 (0.9)	37 (1.0)	0.4
No. inpatient mortality (%)	11 (0.16)	17 (0.47)	0.002