Figure 5From: Multiplex serum biomarker assessments: technical and biostatistical issuesScatter plot of the late-to-early ratio of analyte concentrations versus the late-to-early ratio of assay upper limits of quantitation; a smooth curve is superimposed. Early assays were done on 10/31/2005, 11/01/2005 or 2/17/2006; late assays were done on 5/13/2010.Back to article page