Efficacy and Feasibility of Stroop Test (Smart Phone Application) in the Diagnosis of Minimal Hepatic Encephalopathy

Background and Aim of the Study: Minimal hepatic encephalopathy (MHE) diagnosis is often difficult due to unavailability of screening tests. A combination of test methods is recommended. Present screening tests are cumbersome and time consuming. This study aims to test the efficacy of Stroop test to detect MHE in patients with cirrhosis of liver. Materials and Methods: This cross sectional study includes patients with cirrhosis of any etiology. The control group comprised of non-cirrhotic patients matched for age and level of education. Demographic data were collected and then they were subjected to Number connection test A and Stroop test as per accepted protocol and the results were recorded. Number connection test (NCT) cut-off was computed from the control population usingmean 2SD. Cutoff for Stroop test was then computed using ROC analysis as it was a non-parametric variable. The two tests were then compared in the cirrhotic population using chi-square test and statistical analysis was done using SPSS version 16.0. Results: The study included a total of 101 cirrhotics and 102 controls. Majority of the cirrhotics were male (90%) with alcohol etiology as the majority. The mean Stroop test values in controls (37.16 s) were lower than that for cirrhotics (42.26 s) with a P-value of 0.042. The prevalence of MHE in cirrhotics using NCT (cut-off of 83 s) was 23.76%. Stroop test showed a diagnostic accuracy of 82% with sensitivity of 87.5% and specificity of 80.5% with a cut-off of 43 s obtained after ROC analysis. Conclusions: Stroop test was found to be a valid and feasible measure which was easy to administer, simple to score and interpret. It is a viable addition to the fast growing battery of psychometric tests, the efficacy of which needs to be established in larger prospective trials with relevant clinical end-points.