A new traffic light test could help doctors diagnose liver disease earlier in high risk populations. The Southampton Traffic Light (STL) test, developed by Dr Nick Sheron and colleagues, at the University of Southampton and University Hospital Southampton NHS Foundation Trust, combines several different tests and clinical markers. It is estimated one in five adults in England, some 10 million people regularly exceed Government advice on safe drinking. However because liver disease develops without symptoms, many people have no idea they have liver failure until it is too late. The Department of Health states, “Men should not drink more than three to four units of alcohol a day and women should not regularly drink more than two to three units a day.” The Royal College of Physicians also advises no more than 21 units per week for men and 14 units per week for women. An average pint of beer or lager contains roughly two units of alcohol. A small 125ml glass of ordinary strength wine has one and a half units, while a 25ml shot of a 40 per cent spirit has one unit. The Southampton Traffic Light test combines different tests and indicators, to give a score showing the likelihood of a patient developing a problem. The researchers said, “The test can diagnose liver disease much earlier, enabling those at risk to change their drinking habits, which could save their lives.” They also went on to say, “That while it should not be a substitute for clinical judgment or other tests, it could help GP's determine the potential severity of liver disease, in high risk patients such as heavy drinkers, those with type 2 diabetes or the obese.” Dr Nick Sheron, a consultant at Southampton General Hospital who led the study, and who published his work in the British Journal of General Practice, hopes the test will save lives. He said, “We are reliant on general practitioners detecting liver disease in the community, so they can intervene to prevent serious liver problems developing, but so far we haven't been able to give them the tools they need to do this.” Nurses could take blood from those doctors recommend to be tested one week, for them to return for the results the next. Like traffic lights, the scores are given in three colours. Red will mean the patient already has liver fibrosis and may have cirrhosis. Amber means there is at least a 50:50 chance of scarring, with a significant possibility of death within five years. In such cases patients should be advised to stop drinking, to reduce their chance of developing further diseases, whilst green means there is no cirrhosis. It was given to more than 1,000 patients, and their progress carefully followed, in some cases over several years, to assess the ability of the test to predict the onset of liver fibrosis or cirrhosis. After proving accurate in severe liver disease, it is hoped the test could help GPs accurately assess the potential severity, of liver disease in high risk patients, including heavy drinkers, those with type 2 diabetes, or  people. Dr Sheron said, “It is a powerful tool and a message for people. We find that for most patients this is a pretty good stimulus to stop drinking or at least to cut down to safe levels.” Professor Sir Ian Gilmore, chair of the Alcohol Health Alliance, said, “One of the challenges of liver disease, which is rising dramatically in this country, is the silent nature of the condition, which is that it is often too late to reverse the damage. This large study from Dr Sheron and colleagues in Southampton may prove really useful for guiding the right patients towards specialist care in a timely way.”