Figure 4: Correlating features of the nasopharyngeal swabs and tracheal aspirates.

A) Shannon diversity comparison between nasopharyngeal swabs (N = 124) and tracheal aspirates (N = 98). Mean difference was assessed using Student’s t-test. B) Comparison of the correlation between tracheal aspirate diversity and nasopharyngeal diversity for the 85 paired samples. The strength of the relationship was measured with Pearson’s correlation. C) Chi-square test comparing clusters assigned to the nasopharyngeal swabs against clusters assigned to the tracheal aspirates. A post-hoc chi-square test was used to identify unlikely correlations.