Statistics from Altmetric.com
Contributors CH wrote first draft which was reviewed by BM, AT and TB. All authors agreed final version before submission.
Competing interests None declared.
Patient consent Obtained.
Ethics approval The project was registered with the Standards, Quality and Audit Department and our Service Manager was consulted.
Provenance and peer review Not commissioned; internally peer reviewed.
Correction notice This paper has been amended since it was published Online First. Owing to a scripting error, some of the publisher names in the references were replaced with ’BMJ Publishing Group'. This only affected the full text version, not the PDF. We have since corrected these errors and the correct publishers have been inserted into the references.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.