Chinese research into severe ulcerative colitis has increased in quantity and complexity

Figure 1 Number of Chinese publications regarding ulcerative colitis published in each year from 2001 to 2015. About 13499 ulcerative colitis related articles were published in Chinese medical journals from 2001 to 2015. The annual increase is statistically significant (r = 0.94, P < 0.01). Almost half of the overall papers (6447/13499) were published in the last 5 years (2011-2015). UC: Ulcerative colitis.

Figure 2 Flowchart of study selection. The search of WANFANG, VIP and CNKI databases with the search terms “severe ulcerative colitis” in the Article Title or Keywords retrieved 510 papers when the publication year was limited to the most recent 15 years (2001-2015). Removal of duplicates resulted in 201 individual papers on severe ulcerative colitis (SUC) during this time. We included original research articles and case reports/case series in our analyses of the complexity of SUC research (n = 125).

Figure 3 Annual number of Chinese publications where the prime focus was severe ulcerative colitis from 2001 to 2015. There were 201 severe ulcerative colitis related publications from 2001 to 2015. The increase in the number of publications in each year is statistically significant (r = 0.86, P < 0.01). SUC: Severe ulcerative colitis.

Figure 4 Relative proportions of descriptive studies, observational analytical studies, and clinical trials in every 5-year period from 2001 to 2015. There was a significant increase in observational analytical studies and clinical trials, especially in the most recent 5 years (P < 0.05).

Figure 5 Number of severe ulcerative colitis patients reported in Chinese publications from 2001 to 2015 (shown with each 5-year period). There were 6222 patients reported in 201 severe ulcerative colitis related publications with a significant increase in the number of patients over the time period (r = 0.83, P < 0.01).

Figure 6 Relative proportions of research topics in medical management. About 16 of the 21 observational analytical studies and all of the 36 clinical trials focused on the medical management of severe ulcerative colitis, almost half (46.2%) of them are about Traditional Chinese Medicine.