What is Known: • Alanine aminotransferase (ALT) and ultrasound (US) are the most commonly used tools for detecting non-alcoholic fatty liver disease (NAFLD). • ALT and ultrasound have mediocre accuracy in detecting steatosis in children with obesity.

What is New: • In a head-to-head comparison, the difference in diagnostic accuracy of ALT and ultrasound in detecting steatosis is not significant. • A stepwise screening strategy combining both methods does not improve diagnostic accuracy.