Crude plasma was profiled using Surface Enhanced Laser Desorption/Ionization-Time Of Flight (SELDI-TOF) mass spectrometry. All plasma samples underwent two freeze-thaw cycles prior to analysis. Plasma samples were coded, blinded and randomized before application onto the following solid-phase fractionation surfaces (ProteinChipH arrays Bio-Rad): weak-cation exchange (CM10), strong-anion exchange (Q10) and reverse phase (H50) as previously described [16] . Liquid handling steps were automated using a Biomek 3000 Laboratory Automation Workstation (Beckman Coulter) and a 96 well BioprocessorH (Bio-Rad). Each ProteinChipH 96 well BioprocessorH included 1 quality control plasma standard derived from a single healthy individual, placed at random. Mass spectra were generated on a System 4000 Bio-Rad ProteinChipH mass spectrometer. Spectral peaks corresponding to mass/charge (m/z) clusters were detected and clustered using ProteinChipH Datamanager Client 4.1 software (BioRad). Mass spectrometer calibration was performed using Allin-1 Peptide and Protein calibrants (Bio-Rad). Reproducibility was determined by measuring the inter-ProteinChipH coefficient of variation (CV) for the quality control spectra, based on all peaks in the spectrum with intensity .1 mA. Overall interchip CV for the quality control sample was 20%, consistent with similar studies.