Müller-Hagedorn, Silvia
Wiechers, Cornelia
Arand, Jörg
Buchenau, Wolfgang
Bacher, Margit
Krimmel, Michael
Reinert, Siegmar
Poets, Christian F.
Article History
Received: 24 October 2017
Accepted: 13 April 2018
First Online: 23 April 2018
Ethics approval and consent to participate
: In Germany, retrospective audits aimed at quality improvement do not require ethical approval.
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