Funding for this research was provided by:
National Institute for Health Research (NIHR-RP-02-12-012)
Article History
Received: 9 July 2019
Accepted: 7 November 2019
First Online: 6 January 2020
Ethics approval and consent to participate
: This study was approved by the CPRD Independent Scientific Advisory Committee (protocol reference 16_290).
: Patient consent not required.
: The authors declare that they have no competing interests.