Simple tools for complex syndromes: A three-level difficulty test for hepatic encephalopathy

BackgroundDespite the impact of hepatic encephalopathy on quality of life and prognosis, easily administered tests for its diagnosis are still lacking.AimTo assess the usefulness of the Scan package, a three-level-difficulty computerised reaction time test, to diagnose varying degrees of hepatic encephalopathy.MethodsSixty-one cirrhotic patients underwent clinical evaluation, paper-and-pencil psychometry and the Scan package; 32 healthy controls served as reference.ResultsTwenty-nine patients were classified as unimpaired, 15 as having minimal and 17 as having overt hepatic encephalopathy. All healthy controls were able to complete the Scan package; in contrast, the number of patients who were able to complete three/two/one part decreased in parallel with the degree of encephalopathy (χ2 = 17, p = 0.01). Reaction times in all three parts increased significantly with the severity of encephalopathy. However, the profile of increase was different [group: F(3,77) = 26, p < 0.0001; test: F(2,154) = 277, p < 0.0001; group × test: F(6,154) = 7, p < 0.0001], with different parts being more/less sensitive to varying degrees of encephalopathy.ConclusionsThe Scan package seems useful for the diagnosis of hepatic encephalopathy and covers a considerable portion of its spectrum of severity.