Pekkarinen, Pirkka T. http://orcid.org/0000-0002-8203-3409
Bäcklund, Minna
Efendijev, Ilmar
Raj, Rahul
Folger, Daniel
Litonius, Erik
Laitio, Ruut
Bendel, Stepani
Hoppu, Sanna
Ala-Kokko, Tero
Reinikainen, Matti
Skrifvars, Markus B.
Funding for this research was provided by:
Orionin Tutkimussäätiö
Article History
Received: 19 November 2018
Accepted: 14 February 2019
First Online: 28 February 2019
Ethics approval and consent to participate
: The study was approved by the Ethical committee of the Operative Division of Helsinki University Hospital (194/13/03/02/2014 TMK02 §97), the Finnish National Institute for Health and Welfare (THL/713/5.05.01/2014), Statistics Finland (TK-53-1047- 14), the Finnish Social Insurance Institution (Kela 55/522/ 2015), and the Office of the Data Protection Ombudsman (2794/204/2015). The need for informed consent was waived based on the retrospective non-interventional nature of the study.
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.