To assess the value of Stroop smartphone application (EncephalApp-Stroop) in screening minimal hepatic encephalopathy (MHE).

Ninety hepatitis B cirrhotic patients without overt hepatic encephalopathy (OHE), admitted to our hospital from January 2015 to February 2016, and other 90 healthy volunteers were chosen in our study. Psychometric hepatic encephalopathy scale (PHES) and EncephalApp-Stroop were performed. Normal reference value formulas were established based on the 5 psychometric tests at PHES in healthy controls. EncephalApp-Stroop contained "off" state (neutral stimuli) and "on" state (incongruent stimuli). The time of completing five correct runs and the number of runs in "on" and "off" states were calculated. PHES was used to diagnose MHE as gold standard to compare the results of OHE patients and healthy subjects and the results of patients with/without MHE. EncephalApp-Stroop results were compared with PHES results by receiver operator characteristic analysis.

OHE patients had significantly longer time than healthy subjects in Stroop "on" and "off" states (P<0.05). Traditionally, the total scores of PHES below -4 were diagnosed as MHE, and all the 90 patients taking PHES as gold standard, 52 patients were diagnosed as MHE. The time at Stroop "on" and "off" states and the number of trials completing 5 correct runs were longer/larger in patients with MHE as compared with those in patients without MHE, with significant differences (P<0.05). The validation cohort of EncephalApp-Stroop showed 87% sensitivity and 79% specificity.

The EncephalApp-Stroop is a valid, short and reliable tool for screening MHE.

Hepatitis B cirrhotic; Minimal hepatic encephalopathy; Psychometric hepatic encephalopathy scale; EncephalApp-Stroop