Crane, Melanie A
Jenkins, Christine R
Goeman, Dianne P
Douglass, Jo A
Article History
Received: 1 March 2014
Revised: 21 June 2014
Accepted: 24 June 2014
First Online: 4 September 2014
Competing interests
: The authors declare no conflict of interest. DPG is an Associate editor of <i>npj Primary Care Respiratory Medicine</i>, but was not involved in the editorial review of, nor the decision to publish, this article.