How often people can give blood may be guided by new national study

The INTERVAL study is the first of its kind in the world. It will gather evidence from 50,000 blood donors to see if the length of time between donations can be tailored to individual donors, based on factors such as age, weight, diet and inherited factors.

The study is being run by the universities of Oxford and Cambridge in collaboration with NHS Blood and Transplant (NHSBT).

Participants will be able to take part in the 25 fixed donor centres run by NHSBT across England, with the research project forming part of routine practice at those centres. England is one of the few countries which can run a study of this size due to NHSBT operating as a single organisation with standard practice across all donation venues.

Donating blood can lower the body's iron levels, and blood donation intervals are set to minimise iron deficiency. In England and North Wales intervals are currently 12 weeks for men and 16 weeks for women – but these vary across Europe.

'It is hoped that this new research will provide definitive scientific data to inform optimum donation frequency,' said Professor David Roberts of the Radcliffe Department of Medicine at the University of Oxford, who is leading the study with Professor John Danesh of the University of Cambridge.

'Ultimately we aim to make giving blood even easier by providing more opportunities for a person to donate, whilst at the same time keeping them safe from anaemia,' Professor Roberts added.

NHSBT's medical and research director Dr Lorna Williamson said, 'The aim of this ground-breaking research is to see if donation intervals can be tailored to suit individual donors by age, gender and other characteristics.'

Men taking part in the study will be allocated to donate at intervals of 8, 10 or 12 weeks and women at 12, 14 and 16 week intervals over a period of two years.

Professor John Danesh of the Department of Public Health and Primary Care at the University of Cambridge said: 'In order to examine their iron levels, we will collect blood samples at both the start and end of the trial. Donors will then be monitored throughout the study via an online questionnaire once every six months. There will also be on-line tests of mental function and, for some donors, of physical activity monitoring.'

Recruitment for blood donors to take part in INTERVAL began in June 2012 and will continue into 2013, with results beginning to emerge in 2015. By mid-September, around 7,500 donors had already enrolled to take part in the study.

Anyone wishing to take part in the INTERVAL study must be able to give blood when called at one of NHSBT's fixed donor centres, be 18 years or over and have access to the internet with a valid email address.

Provided by Oxford University