Weekday vs weekend endoscopy: Is there a true difference in patient outcomes? A meta-analysis

Table 1 Details described on the studies included in meta-analysis

Ref.	Study type	Location	Time	# of Pts	Group	Pts/Group
Youn et al[3]	Retrospective	South Korea	1/07-12/09	388	Weekend	62
	4 centers				Weekday	326
de Groot et al[4]	Prospective	The Netherlands	10/09-9/11	571	Weekend	167
	8 centers				Weekday	404
Byun et al[9]	Retrospective	South Korea	1/05-2/09	294	Weekend	74
	1 center				Weekday	220
Jairath et al[11]	Retrospective	United Kingdom	5/07-6/07	6749	Weekend	1499
	212 centers				Weekday	5250
Button et al[22]	Retrospective	Wales	4/99-3/07	24421	Weekend	5686
	22 centers				Weekday	18285
Dorn et al[18]	Retrospective	United States	1998-2003	98975	Weekend	23339
	NIS database				Weekday	75636
Shaheen et al[1]	Retrospective	United States	1993-2005	237412	Weekend	57270
	NIS database				Weekday	180142
Myers et al[10]	Retrospective	United States	1998-2005	36734	Weekend	9237
	NIS database				Weekday	27497
Ananthakrishnan et al[2]	Retrospective	United States	2004	419939	Weekend	97002
	NIS database				Weekday	322937
Bell et al[14]	Retrospective	Canada	4/88-3/97	45167	Weekend	3602
	190 centers				Weekday	41565
Haas et al[8]	Retrospective	United States	1/08-10/08	174	Weekend	50
	1 center				Weekday	124

Table 2 Quality assessment of the studies based upon the effective public health practice project scale

Ref.	Selection bias	Study design	Confounders	Blinding	Data collection method	Withdrawals and dropouts	Overall assessment
Youn et al[3]	Moderate	Moderate	Weak	N/A	Strong	N/A	Moderate
de Groot et al[4]	Strong	STRONG	Moderate	N/A	Strong	Strong	Strong
Byun et al[9]	Weak	Moderate	Weak	N/A	Strong	N/A	Weak
Jairath et al[11]	Strong	Moderate	Weak	N/A	Strong	N/A	Moderate
Button et al[22]	Strong	Moderate	Weak	N/A	Strong	N/A	Moderate
Dorn et al[18]	Strong	Moderate	Weak	N/A	Strong	N/A	Moderate
Shaheen et al[1]	Strong	Moderate	Weak	N/A	Strong	N/A	Moderate
Myers et al[10]	Strong	Moderate	Weak	N/A	Strong	N/A	Moderate
Ananthakrishnan et al[2]	Strong	Moderate	Weak	N/A	Strong	N/A	Moderate
Bell et al[14]	Strong	Moderate	Weak	N/A	Strong	N/A	Moderate
Haas et al[8]	Weak	Moderate	Weak	N/A	Strong	N/A	Weak

N/A: Not applicable.