**8. Acknowledgment**

Professor David Johnson is a recipient of consultancy fees, research grants, travel sponsorships and speakers' honoraria from Amgen, Roche and Janssen-Cilag. He is a recipient of consultancy fees from Sandoz and is a co-investigator on industry-sponsored research by Amgen, Roche and Janssen-Cilag. He is currently supported by a Queensland Government Health Research Fellowship. Other authors do not have any conflicts of interest to declare.
