You can use this rest to show that you have stopped or reduced your alcohol consumption or to see if you will pass the DVLA medical. If you drink steadily and heavily (four-six units of alcohol per day) for several weeks, the percentage of transferrin that is deficient in carbohydrates will rise. The longer you drink at this level, the higher the level of CDT.
Our test is analysed using a different method from the official DVLA laboratory. It will not be possible to get a result for around 2% of people taking this test due to a normal genetic variant in transferrin. If this applies to you, an alternative test will be recommended.