7. Hospital stay small‐incision vs open cholecystectomy: all available data.

Trial	Type of data	SIC ‐ mean/median	SIC ‐ SD/range	OC ‐ mean/median	OC ‐ SD/range	Skewness SIC	Skewness OC
Assalia 1993	A ‐ SD	3	0.4	4.7	0.8	7.5	5.88
Coelho 1992a	A ‐	1,7	‐	3,5	‐	‐	‐
Coelho 1993	A ‐ range	1	1 ‐ 1	2	2 ‐ 3	‐	‐
O'Dwyer 1992a	M ‐ range	3	1 ‐ 10	5	3 ‐ 8	‐	‐
Schmitz 1997a	A ‐ SD	11.5	1.2	15.4	2.5	9.58	6.16
Seenu 1994	A ‐ range	2.6	1 ‐ 4	4	3 ‐ 8	‐	‐
Wani 2002	A ‐	3	‐	5	‐	‐	‐
	A: Average / mean	SD: standard deviation	M: median