BACKGROUND : To evaluate the usefulness of point-of-care ultrasound (POCUS) performed by young military medicine residents after short training in the diagnosis of medical emergencies. METHODS : A prospective study was performed in the emergency department of a French army teaching hospital. Two young military medicine residents received ultrasound training focused on gall bladder, kidneys and lower limb veins. After clinical examination, they assigned a 'clinicaldiagnostic probability' (CP) on a visual analogue scale from 0 (definitely not diagnosis) to 10 (definitive diagnosis). The same student performed ultrasound examination and assigned an 'ultrasounddiagnostic probability' (UP) in the same way. The absolute difference between CP and UP was calculated. This result corresponded to the Ultrasound Diagnostic Index (UDI), which was positive if UP was closer to the final diagnosis than CP (POCUS improved the diagnostic accuracy), and negative conversely (POCUS decreased the diagnostic accuracy). RESULTS : Forty-eight patients were included and 48 ultrasound examinations were performed. The present pathologies were found in 14 patients (29%). The mean UDI value was +3 (0-5). UDI was positive in 35 exams (73%), zero in 12 exams (25%) and negative in only one exam (2%). CONCLUSIONS : POCUS performed after clinical examination increases the diagnostic accuracy of young military medicine residents.