Worth, Allison
Hammersley, Victoria
Knibb, Rebecca
Flokstra-de-Blok, Bertine
DunnGalvin, Audrey
Walker, Samantha
Dubois, Anthony E J
Sheikh, Aziz
Article History
Received: 10 February 2014
Accepted: 8 April 2014
First Online: 26 June 2014
Competing interests
: The authors declare that they have no conflicts of interest in relation to this paper. AS is Joint Editor-in-Chief of the <i>PCRJ</i>, and BFdB is an Associate editor of the <i>PCRJ</i>, but neither was involved in the editorial handling, review or decision-making process in relation to this article. AS was supported by The Commonwealth Fund, a private independent foundation based in New York City. The views presented here are those of the author and not necessarily those of The Commonwealth Fund, its directors, officers, or staff.