Figure 1

Gut microbiota diversity in the fecal samples of the experimental groups of subjects. Boxplots show (a) the total number of OTUs, (b) Chao index and (c) Simpson’s eveness indexes in patients with established SSc and gastrointestinal symptoms (SSc/GI+), patients with SSc without gastrointestinal symptoms (SSc/GI-), and healthy controls (HC), respectively. Significant differences are highlighted by different minor letters according to ANOVA and Tukey’s honestly significant difference (HSD) test for comparison of means (P < 0.05).