Fig. 4

Longitudinal covariation of bacterial relative abundances and clinical signs of oral mucositis during chemotherapy. a A circle correlation plot depicting covariation of salivary bacterial abundances with oral mucositis severity (OMAS) and other significant clinical variables, as determined via multi-level sPLS analysis. Bacterial species appear as red circles and clinical variables are shown as blue triangles. Data points were placed in the plot according to their correlation with the two main components. Positively correlated variables follow the same direction from the origin. The greater the distance from the origin, the stronger the association. Only variables with a correlation coefficient greater than 0.4 are shown. Red numbers and corresponding names indicate bacterial species positively correlated with OMAS (enriched as mucositis severity increased), while black numbers and names indicate bacterial species negatively correlated with OMAS (depleted during severe mucositis). SFR salivary flow rate, MD AB multi-dose antibiotic intake; b a similar analysis done for mucosal bacterial taxa. Bacterial species appear as orange circles and clinical variables as blue triangles. Red numbers and names indicate species positively correlated with OMAS, while black numbers and names indicate bacterial species negatively correlated with OMAS