Duodenum-Preserving Resection of the Pancreatic Head versus Pancreaticoduodenectomy for Treatment of Chronic Pancreatitis with Enlargement of the Pancreatic Head: Systematic Review and Meta-Analysis

Table 1

The characteristics of all the included studies.

Author	Year	Country	Study type	Group	Patients number	Male/female	Age, y	Study quality
								RCT(jadad system)
								retro(NOS system)
Keck et al. [8]	2012	Germany	RCT	Beger	42	35/7	41.2	5
				PD/PPPD	43	37/6	42.7
Strate et al. [9]	2008	Germany	RCT	Frey	31	25/6	43.1 ± 6.5	5
				PD/PPPD	30	26/4	44.6 ± 5.3
Müller et al. [10]	2008	Germany	RCT	Beger	20	18/2	43.0 ± 9.0	5
				PD/PPPD	20	18/2	46.0 ±11.0
Farkas et al. [11]	2006	Germany	RCT	Frey	20	15/5	43.0 ± 5.0	5
				PD/PPPD	20	15/5	45.0 ± 8.0
Helmut et al. [12]	2002	Germany	RCT	Beger	35	—	43	7
				PD/PPPD	30	—	48
Izbicki et al. [13]	1998	Germany	RCT	Frey	31	19/9	43.0 ± 5.0	5
				PD/PPPD	30	19/10	45.0 ± 8.0
Klempa et al. [14]	1995	Germany	RCT	Beger	22	—	—	5
				PD/PPPD	21	—	—
Büchler et al. [15]	1995	Germany	RCT	Beger	20	25/9	43.0 ± 9.0	7
				PD/PPPD	20	12/8	46.0 ± 11.0
Zheng et al. [16]	2012	China	Retro	DPPHR	66	21/16	46.0 (8.8)	7
				PD/PPPD	57	23/14	45.6 (9.7)
Hildebrand et al. [17]	2010	Germany	Retro	Frey	22	8/14	46.6 ± 9.1	7
				PD/PPPD	59	26/33	54.1 ± 9.7
McClaine et al. [18]	2009	America	Retro	DPPHR	22	8/14	44.9 ± 11.1	9
				PD/PPPD	59	26/33	46.8 ± 11.1
Möbius et al. [19]	2007	Germany	Retro	DPPHR	29	—	—	7
				PD/PPPD	24	—	—
Belina et al. [20]	2005	Czech	Retro	Frey	48	39/9	45 (23–71)	7
				PD/PPPD	56	55/1	48 (29–71)
Witzigmann et al. [21]	2003	Germany	Retro	DPPHR	38	28/10	42 ± 10	9
				PD/PPPD	32	25/7	47 ± 12
Kelemen and Horváth [22]	2002	Japan	Retro	Beger	32	13/0	45.3 (36–64)	7
				Frey	13	26/6	45.9 (36–58)
				PD/PPPD	21	19/2	48.2 (31–70)

RCT: randomized controlled trial, PD/PPPD: pancreaticoduodenectomy, and DPPHR: duodenum-preserving pancreatic head resection. Jadad scale system: The Jadad scale, sometimes known as Jadad scoring or the Oxford quality scoring system, is a procedure to independently assess the methodological quality of a clinical trial. It is the most widely used assessment in the world. The Newcastle-Ottawa System: the quality of the nonrandomized studies was assessed by using this system. The quality of the studies was evaluated by examining three items: patient selection, comparability of groups, and assessment of outcome.