Figure 2
From: Comprehensive characterisation of pulmonary and serum surfactant protein D in COPD
Repeatability of SP-D measurements. Bland-Altman plot to assess the repeatability of SP-D levels in BAL (A) and serum (B) of elderly smokers (S2) and smokers with COPD between two samplings with a time delay of about 34 ± 10 days. The coefficient of reliability (derived from one-way ANOVA as the ratio of variance among subjects to total variance) is given as intraclass correlation coefficient (ICC).