[Technical quality assurance in diagnostic ultrasound in outpatient care in Germany]

Technical quality assurance in diagnostic ultrasound is based on nationally standardized protocols which are mandatory for outpatient care in Germany. Quality assurance includes technical requirements for sonographic instruments based on limiting values for technical parameters and requirements for image quality and documentation. Certification by regional Associations of Statutory Health Insurance Physicians (Kassenärztliche Vereinigungen - KV) requires acceptance tests to prove compliance with all required standards.

Between April 2009 und December 2011a total of 7457 acceptance tests were performed by the KV Westfalen-Lippe, which represents nearly 13 000 physicians in northwestern parts of Germany. Results of these acceptance tests are evaluated with respect to display mode or Doppler technique, anatomic region and year of manufacture of the instruments.

In 2469 acceptance tests (33 %), objections were raised, mainly due to noncompliance with technical parameters. The frequency of objections strongly increases with the age of sonographic instruments and exceeds 90 % for instruments manufactured before 1995. In acceptance tests where compliance with technical parameters has been approved, insufficient documentation was reported in 6 % and inadequate image quality in 8 % of the tests. Frequency and cause of objections depend on display mode and anatomic region.

The study shows that sonographic instruments of higher age often do not meet the required standards, and it can be expected that updates in technical equipment will result in improvements in diagnostic performance and clinical outcome.