Once blood samples have been retrieved from the EPIC-Heart cases, biomarker assays can begin on the EPIC-Heart cases, the InterAct cases and the shared control cohort. The specific objectives relating to the measurement of biomarkers in EPIC-Heart are:

• to select and prioritise both standard analytes and novel vascular biomarkers to be assayed with the available resources;
• to identify the optimal partner laboratory to undertake the required assays on the necessary scale;
• to undertake the assay of standard analytes and novel vascular biomarkers in the case-cohort study and to deliver complete and accurate data to the central datahub;
• to develop and implement strategies for repeat measurements to allow for correction for regression dilution bias;