Introduction
DBS and venous blood sample, death, Cardiovascular disease
DISEASE, CARDIOVASCULAR DISEASE, CARDIOVASCULAR DISEASE
Cardiovascular disease is the leading cause of death worldwide. In the UK, cardiovascular disease is patterned by several social and environment factorsStandard protocols for blood sample collection require face-to-face contact. Most commonly, collection of bio-specimens for research takes place in a clinic and/or the participant’s home by a trained phlebotomist or nurse. Research clinics, typically a medical or research facility or ‘mobile clinic’, provide expert medical personnel, phlebotomists, and specialised equipment to ensure the appropriate handling of samplesThe resource challenges of the above approaches can be addressed by dried blood spot (DBS) sampling, which is a low resource-demanding alternative to venous blood draws, and as less invasive, may be more acceptable to participants. DBS samples are small volumes of capillary blood, obtained by fingerprick and blotting of the blood onto filter paper. This method, which has been used in new born screening programmes, reduces personnel and shipping costs, and is an accepted means of collecting blood samples in a research settingA number of social studies such as National Social Life, Health, and Aging projectFor the successful use of DBS in population surveys, it needs to be demonstrated that the characteristics of participants that complete a DBS collection are not systematically different compared to those that provide venous blood. Further, to enable population level estimates of disease, it is necessary to determine whether analyte concentrations measured in DBS and venous blood samples are equivalent. To address these issues, we included DBS and venous blood sample collection in a randomised study of the general population. The aims of this study were (a) to describe the demographic characteristics of participants that took part in the survey, consented to give venous and/or DBS samples, and who provided good quality DBS samples; (b) to estimate serum-equivalent DBS values and compare results to venous samples, investigating how blood sample characteristics affects the agreement between the two measures; c) to investigate if serum-equivalent DBS measures are suitable to assess clinical risk.