Figure 4

Partial least squares discriminant analysis (PLS-DA) loading plot based on the relative abundance of bacterial taxa determined by 454 sequence analysis of the microbiota of sputum from patients with greater than 3 exacerbation event per annum (green circle) and sputum from patients with 3 or fewer exacerbation events per annum (blue circle). PLS1 (R ² X = 0.0701, R ² Y = 0.232, Q ² = 0.0467) and PLS 2 (R ² X = 0.0477, R ² Y = 0.124, Q ² = 0.0601) are given. The solid ellipse indicates Hotellings T ² range, at 95% confidence. Patient samples falling outside of the ellipse are deemed to be the major outliers. Some sample labels have been removed for ease of interpretation.