Questions & Answers

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Question When will we be able to order online? Phoning you from New Zealand is nice but not that convenient!
Answer Now! Since 2011 we have used a telephone order line. This had the advantage that we had personal contact with users. However time differences and issues of taking down orders correctly has been an increasing problem for overseas users. We have now (April 2017) put in place a eCommerce ordering - currently using a partner in Birmingham to help with this.
Please explain the units  - you use nmol/L and other labs use ng/mL? How do you convert from one to the other
Answer The nmol/L unit  is the on that all UK laboratories have been instructed to move to if they are not already using it - see To convert nmol/L to ng/mL divide by  a factor of 2.5.
e.g. Our result is 75 nmol/L would give 75/2.5 = 30 ng/mL
Do you do any other tests - for example serum calcium and iron studies direct to the public?
Answer The only test we currenlty offer to the public is Vitamin D. We may develop other services in the future but this will depend on full consideration of ethical issues and also the practicalities, as not everything is measurable on a blood spot sample 
Thank you for my ultra clear test results. Could I just check - your results state that greater than 50nmol/l is normal. My understanding is that total 25-hydroxyvitamin D should be over 75 nmol/L. 
Answer Vit D deficiency historically is defined as a blood level below 25 nmol/L  and many NHS laboratories quote this range. Scientific evidence is emerging that the optimal level for general health may be higher than 50 nmol/L but we will stay with this a the moment.
Question I am trying to determine how long to wait before retesting my vitamin D after increasing my supplementation?
Answer A paper from 1999 by Reinhold Vieth has information relevant to this and can be downloaded here......
Question How many times can I send in a test to you?
Answer For personal use we do not recommend that you test yourself more than twice a year. Some people are ordering multiple packs for use in their job or for research and group studies and this is fine.
Question What turn round do you offer for this test?
Answer Our aim is 5 working days laboratory time.
Question Are these packs suitable for a research project? Do you discount for bulk   purchase?
Answer   Yes, in fact the packs are already being used for a research project in Cambridge and interestingly also to study Vitamin D levels in animals at Chester Zoo! Our introductory prices are very competitive and we do not intend to discount them.
Question Can you send the test packs overseas?
Answer   Yes, but we do need to charge a bit more. You will also need to add airmail postage to the reply paid envelope locally
Question When are you starting this service?
        Answer We are now trialing this Direct to the Public Service and you can order test packs from us by phoning our call centre number: Tel: 0121 507 4278.

Ordering a Test Kit

  • Order online

  • Telephone orders: +44 (0)121 507 4278 Mon-Fri 09.00 - 17.00 UK time.

Video showing how to do the test:

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