Trial registration

\label{trial-registration}
Having gained ISRCTN registration for our previous study of Twitter (ISRCTN84658943) we applied again but now these identifiers are now only supplied for randomised trials involving human participants.

Funding

\label{funding}
This study is largely undertaken on intramural support from the University of Nottingham. Modest extramural funding was gained for facilitating this and other studies (£15K, Economic and Social Research Council, UK) and for holding a one day study design meeting for medical students (£2.5K, Economic and Social Research Council, UK).

Acknowledgements

\label{acknowledgements}
The research team is grateful to Julie Wood and the Communications and External Affairs team of the Cochrane Collaboration who gave permission for use of the access code for the summaries pages via Google Analytics.
Thanks also to Joanne Thomas and Max Goldman (Sense about Science - senseaboutscience.org) who helped with the language to be used within the tables.
We also wish to thank James Heilman (Wikipedian, The Wikipedia Open Textbook of Medicine) for his ongoing support in seeding Wikipedia with good evidence.