Retrospective Cohort Study
Copyright ©The Author(s) 2020.
World J Gastroenterol. Aug 7, 2020; 26(29): 4302-4315
Published online Aug 7, 2020. doi: 10.3748/wjg.v26.i29.4302
Figure 1
Figure 1 Geographical locations of the centres. The map shows the four centers in China and Europe: Xining in central China and Urumqi in the northwest of the country; Besançon in eastern France, and Ulm in southwestern Germany.