Does chronic kidney disease affect the complications and prognosis of patients after primary colorectal cancer surgery?

Table 1 Characteristics of the studies included in the meta-analysis

Ref.	Country	Study design	Study date	Sample size			Definition of CKD and non-CKD		NOS
				CKD group	Non-CKD group	Total	CKD group	Non-CKD group
Currie et al[15], 2014	United Kingdom	Prospective	2006-2011	126	582	708	15 < eGFR < 60	eGFR ≥ 60	7
Nozawa et al[17], 2012	Japan	Retrospective	2001-2010	245	882	1127	eGFR < 60	eGFR ≥ 60	8
Higashino et al[16], 2020	Japan	Retrospective	2008-2015	14	567	581	Dialysis	Non-dialysis	7
Hu et al[18], 2015	United States	Retrospective	2009-2013	265	42138	42401	Dialysis	Non-dialysis	8
Chen et al[26], 2016	China	Retrospective	2012-2015	5	10	15	eGFR < 60	eGFR > 60	6
Obara et al[25], 2021	Japan	Retrospective	2007-2016	24	24	48	Dialysis	Non-dialysis	8
Obara et al[27], 2022	Japan	Retrospective	2011-2015	59	204	263	eGFR < 55	eGFR ≥ 55	7
Shiraishi et al[28], 2022	Japan	Retrospective	2016-2020	78	1294	1372	eGFR < 60	eGFR ≥ 60	8
Dudani et al[29], 2021	Canada	Retrospective	2005-2013	136	1118	1254	eGFR < 60	eGFR > 60	8

CKD: Chronic kidney disease; eGFR: Estimated glomerular filtration rates (mL/min/1.73 m²); NOS: Newcastle-Ottawa Scale.