Strongman, Helen
Brown, Adam
Smeeth, Liam
Bhaskaran, Krishnan
Funding for this research was provided by:
Wellcome Trust (107731/Z/15/Z)
Royal Society (107731/Z/15/Z)
Article History
Received: 3 September 2018
Revised: 21 January 2019
Accepted: 22 January 2019
First Online: 27 February 2019
Competing interests
: The authors declare no competing interests.
: The data that support the findings of this study are available from CPRD, but restrictions apply to the availability of these data, which were used under license for the current study, and so are not publicly available.
: The study was approved by the London School of Hygiene and Tropical Medicine Ethics Committee (Ref 13843) and the pre-specified scientific protocol was approved by the Independent Scientific Advisory Committee for MHRA Database Research (isac@cprd.com; protocol 12_090A3).