Welcome to your CLOTS Website!


The CLOTS Trial is a research study

The CLOTS study aims to find out whether graduated compression stockings or Intermittent Pneumatic Compression sleeves reduce the risk of a person admitted to hospital with a stroke developing a deep vein thrombosis (DVT).

The CLOTS study actually comprises three trials comparing alternative treatments to see which are best

  • Trial 1 is comparing Long stockings with No stockings (completed - results available)
  • Trial 2 is comparing Long stockings with Short stockings (completed - results to be published in 2010)
  • Trial 3 is comparing Intermittent Pneumatic Compression (IPC) with No IPC (ongoing - results expected in 2014)

Progress Report & Results so far    

Joining a CLOTS study

People who have had a stroke and who are admitted to a hospital participating in the CLOTS trial may be asked whether they would like to join the study. Only those patients unable to walk without help from another person are suitable for the trial. If the person can walk on their own they are at lower risk of developing a deep vein thrombosis.

Before the patient is entered into the trial they will be given an explanation of the research by a nurse or a doctor. They will be given a patient information leaflet. The patient is only entered into the study if they wish to. Before entering the study they will, if they can write, complete a consent form. If the person with the stroke has a problem speaking or understanding then a close family member or friend may consent for them.

Consent just means that the person with the stroke has agreed to participate in the trial. Normally this is recorded on a special form which the person or a relative or friend signs.

Allocating the treatment

The doctor or nurse who has invited the person with the stroke to join the study will fill in a randomisation form which includes details of the person, their stroke and their treatment. The doctor or nurse puts the information on this form into a secure computer in Edinburgh via the internet or telephone. The computer then sends a message back indicating which treatment the person should receive. The computer chooses the treatment at random - like tossing a coin - heads the patient gets one treatment, tails the other. This random allocation of treatment ensure that groups of patients taking the treatment are similar to each other.

The nurse applies the type of stockings or IPC chosen by the computer. The patient will normally wear the stockings or IPC until they are able to walk on their own or until they leave hospital - whichever occurs first. They will usually wear them continuously, both day and night. However, if the patient with the stroke decides not to wear the stockings anymore they can choose to have them taken off.