Fig. 1

Annual ultrasound productivity and number of GPs offering ultrasound between 2004 and 2018. US: ultrasound; US productivity refers to the annual number of ultrasound exams per physician-year. * 2018 data is up to 30 September 2018. The yearly values are based on those GPs that performed at least one ultrasound examination in the respective year. The overall values are based on all GPs, i.e., they performed at least one ultrasound across all years