Received: 22 December 2019
Accepted: 8 February 2020
First Online: 22 February 2020
Compliance with ethical standards
: JW, SR, GK and PR declare that they have no conflict of interest. AS received personal fees as speaker honoraria/consulting fees from Merck/Schering-Plough, AbbVie, Bayer, UCB, Novartis, BMS, Lilly, Sanofi Aventis, and Lilly, and unrestricted collaboration research grant to Diakonhjemmet Hospital from Lilly.