Efficacy and effectiveness of liver screening program to detect fatty liver in the periodic health check-ups.

To determine whether the current liver screening program for fatty liver has sufficient scientific evidence to justify its continued implementation. The liver screening program to detect fatty liver was performed on 411 Japanese workers utilizing serum aspartate aminotransferase (ALT), alanine aminotransferase (AST), and gammaglutamyl transpeptidase (gamma-GTP). Based on the preceding studies, subjects with viral and alcohol hepatitis were excluded from the evaluation. The diagnosis of fatty liver was based on ultrasound findings. The program was evaluated by efficacy and effectiveness; efficacy was measured according to the receiver operating characteristic (ROC) curves in comparison with the Body Mass Index (BMI). Effectiveness, based on the efficacy determinations, was assessed by means of the positive predictive value (PPV) test performance, the disease characteristics, and the program price. The diagnostic performances of ALT and BMI were nearly acceptable but far from excellent. The areas under the curves of the two indices were 0.69 and 0.63, respectively and these were statistically equivalent. The PPV ranged from 15 to 28% where the prevalence of fatty liver was 12.3%. The price of the program was estimated at US 4 dollars per person based on the medical reimbursement fee rate. The efficacy of the liver screening program was found to be insufficient and BMI monitoring may provide a more suitable and inexpensive alternative. Furthermore, the effectiveness of the program is open to question, considering the generally benign prognosis of the disease in the absence of any accompanying morbid conditions and the high price of the program.