Fig. 3

Mean (± SEM) serum concentrations of activin proteins and a representative cytokine as summarised by weighted standing time (WST), namely, (a) activin A (pg/mL), (b) activin B (pg/mL), (c) follistatin (ng/mL), and (d) interleukin-10 (IL-10) (pg/mL). WST classes are: Healthy study controls (0), ME/CFS—mild (1), ME/CFS—moderate (2), and ME/CFS—severe (3) WST class definitions are presented in Table 3