Impact of time before (a,b,c) and after (d-g) centrifugation on measured VEGF-A and PF-4 levels.

<p>In some EDTA samples, VEGF-A (a,c,d) and PF-4 levels (b,f) increased with longer incubation times. This was particularly significant when EDTA samples were stored for longer periods of time before centrifugation (c). In PECT samples (c,e,g), VEGF and PF-4 values were not affected by longer sample storage times.</p

Overview of sample acquisition procedures and the distribution of samples from blood acquisition centers to measuring centers and central laboratory.

<p>Overview of sample acquisition procedures and the distribution of samples from blood acquisition centers to measuring centers and central laboratory.</p

(a) Scatter plot for the influence of cannula (neonatal vs. butterfly) on measured VEGF-A plasma levels; (b) Scatter plot for intrapersonal fluctuations in plasma VEGF-A levels over one week; (c) Scatter plot for the impact of filling level of blood collection tubes on the resulting VEGF-A levels.

<p>Location of values near the bisecting line indicates comparable measurement results.</p