Background and Aims: Psychometric hepatic encephalop-athy score(PHES)is used widely for diagnosis of minimal hepatic encephalopathy(MHE).This prospective study aimed to determine the utility of the inhibitory control test(ICT)for the diagnosis of MHE.Additionally,the efficacy of rifaximin and lactulose for reversal of MHE was evaluated.Methods:A total of 180 eligible cirrhotic patients underwent testing for MHE.When PHES was ≤ ?5 and ICT lures were ≥ 14,MHE was diagnosed.The 108 patients with MHE were randomized to three groups for treatment with either lactulose,rifaximin,or placebo.Treatment outcomes were measured at the end of 3 months.Results: The 108 patients with MHE diagnosed by PHES and/or ICT accounted for 60％.The diagnosis of MHE was made by both ICT and PHES positivity in 56 patients,by abnormal ICT and normal PHES in 37 patients,and by abnor-mal PHES and normal ICT in 15 patients.For diagnosis of MHE,ICT had sensitivity of 78.87％,specificity of 66.06％with 60.22％positive predictive value and 82.76％negative predictive value.An area under the curve value of 0.724(95％CI: 0.653–0.788)was obtained for diagnosis of MHE.Reversal of MHE was seen in 71.42％,70.27％and 11.11％of patients in the rifaximin,lactulose and placebo arms(p < 0.001).Rifaximin showed better tolerability compared to lactulose.Conclusions: For the diagnosis of MHE,ICT is a simple tool but has lower sensitivity and better specificity than PHES.Rifaximin is as efficacious as lactulose in the treat-ment of MHE and better tolerated.