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. 2016 May 16;353:i2416. doi: 10.1136/bmj.i2416

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Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions

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graphic file with name damj031028.f2_default.jpg — Fig 2 Numbers of articles in which only one or more models were developed (dark blue), only one or more models were externally validated (light blue), or one or more models were developed and externally validated (white), ordered by publication year (up to June 2013). Predictions of the total numbers in 2013 are displayed with dotted lines