Glossary Please select an letter from the A-Z list or search # A B C D E F G H I J K L M N O P Q R S T U V W X Y Z false negative When a person has a medical condition but is diagnosed as not having it. false positive When a person does not have a medical condition but is diagnosed as having it. fatigue Tiredness, often severe (exhaustion). FibroScan A non-invasive test, used instead of a biopsy, to measure the stiffness or elasticity of the liver using an ultrasound probe. fibrosis Scarring of the liver – the development of hard, fibrous tissue. See also ‘cirrhosis’, which is more severe scarring. FibroTest A test that uses results from blood tests to predict liver damage. first-line therapy The regimen used when starting treatment for the first time. flare A rapid elevation of liver enzymes such as alanine aminotransferase (ALT) or aspartate aminotransferase (AST). flatulence Passing gas from the digestive system out of the anus, or back passage (also called 'passing wind' or 'farting'). foetus An unborn baby. folliculitis Infection of the follicles, small sacs or glands in the skin such as those found at the base of hairs. follow-up The period of time that a person takes part in a study. fulminant Occurring or flaring up suddenly and with great severity. fungi A group of organisms, including the yeasts which cause candidiasis and cryptococcosis. futility rule See ‘stopping rule’.