Welcome to the QThrombosis®-2018 risk calculator: http://qthrombosis.org

This calculator is not suitable if you have a history of venous thrombosis, a family history of thrombosis, are pregnant, are taking anticoagulants, or have symptoms suggestive of a thrombosis.

About you
Age (25-84):
Sex: Male Female
UK postcode: leave blank if unknown
Clinical information
Smoking status:
Do you have or have had any of the following...
varicose vein surgery?
chronic kidney disease (stage 4 or 5)?
heart failure?
chronic obstructive airways disease?
crohns or ulcerative colitis?
Have you been...
admitted to hospital in last 6 months?
Are you taking any of the following...
Women only
hormone replacement therapy (HRT)?
an oral contraceptive?
Leave blank if unknown
Body mass index
Height (cm):
Weight (kg):
Calculate risk over years.

Welcome to the QThrombosis® risk calculator

Welcome to the QThrombosis® Web Calculator. You can use this calculator to work out your risk of developing a venous thromboembolism by answering some simple questions.

It has been designed to assess future risk of thrombosis in patients without symptoms. It is not designed to be used when making a diagnosis of thrombosis.

The QThrombosis® algorithms have been developed by Julia Hippisley-Cox and Carol Coupland and are based on routinely collected data from many thousands of GPs across the country who have freely contributed data to the QResearch database for medical research.

QThrombosis® has been developed for the UK population, and is intended for use in the UK. All medical decisions need to be taken by a patient in consultation with their doctor. The authors and the sponsors accept no responsibility for clinical use or misuse of this score.

The science underpinning the QThrombosis® algorithms has been published in the BMJ. Please see the "Publications" page for more details.