Figure 2

Combination of clinical characteristics associated with groups from VIStA. A Number of times the characteristics were found significantly different between group 1 & 2 in a total of 500 divisions. Severity of airflow limitation (GOLDCD) is the single most important determinant of differential gene expression, being statistically significant in 95% of all VIStA outputs. B Summary of the individual and pairwise number of significant occurrences of the clinical characteristics. Node size is proportional to the number of times a measure was found significant, the width of a link indicates how often two measures appeared significant in the same VIStA division. The core group contains severity of airflow limitation (GOLDCD) and the two emphysema measures EMPHETCD and FV950. C, Number of times that pairwise combinations of clinical characteristics co-occurred in the 500 VIStA outcomes. The most significant pair (as compared to a Null model of independent occurrence) is EMPHETCD and FV950, which are both measures of emphysema. D The most frequent and significant triplet is a combination of GOLDCD and EMPHETCD and FV950, measuring disease severity. E We find significant combinations of the disease severity triplet in B with four clinical characteristics: BMI, PHLEGM, DWALK and AGE.