List of repeatable biomarkers in the lung compartments (for all markers with ICC>0.60).

Intraclass correlation coefficients (ICC) were derived from one-way ANOVA tables as the ratio of variance among subjects to total variance based on 2 measurements over a 6 week period (for log transformed data only) r: Pearson correlation coefficient. Data is sorted by matrix and decreasing ICC as derived from all subjects. Some markers are listed due to ICC>0.6 in the subgroups (in bold). Mean SD (Standard Deviation) values were derived from log-transformed data of the 2 visits, transformed again and listed for the 2 subgroups. This way these values are factors. To derive the SD value, that together with the median values of a marker (listed in table 4 and in the Online Supplement) can be used for sample size and power calculations, the respective median needs to be multiplied and divided by the value listed above (Example for HSA in BAL fluid of COPD patients: Approximate level of HSA in BAL is 11 µg/mL (table 4), the SD is 1.5×11–11/1.5 = 16.5–7.3 = 9.2 µg/mL). CD14 monocytes are displayed as % total cell count, CD16 neutrophils are displayed as 103cells/mL, TP: normalized to total protein, Mono: monocytes, NG: neutrophils, TCC: total cell count, EP: non-squamous epithelia cells, AM: macrophages.