The authors acknowledge the special input of members of the working group: Inga Bjornevoll, Cristophe Cordier, Miguel del Campo, Yurgagul Erdem, Ulrika Hosterey-Ugander, Lisa Jeffers, Milena Paneque, Sari Rasi, Vigdis Stefansdottir, Fulya Teksen and Conny van der Meer.
Conflict of interest
The authors declare that they have no conflict of interest.