Brief Article
Copyright ©2012 Baishideng Publishing Group Co.
World J Gastroenterol. Oct 28, 2012; 18(40): 5779-5788
Published online Oct 28, 2012. doi: 10.3748/wjg.v18.i40.5779
Figure 1
Figure 1 Flow diagram of the identification of the relevant cohort studies and case-control studies.