Funding for this research was provided by:
National Institute for Health Research (NIHR) School of Primary Care Research
Received: 26 July 2017
Accepted: 25 January 2018
First Online: 26 February 2018
Ethics approval and consent to participate
: Routinely collected electronic data used as part of this study was approved by a THIN Scientific Review Committee of the Cegedim Strategic Data Medical Research United Kingdom (the data provider).
: The Health Improvement Network (THIN) is a large primary care database containing longitudinal anonymised medical records of patients. Access to these records is subject to approval from the respective scientific review board. Patients are given the option to have their de-personalised medical records collected for scientific research purposes, therefore patients consent are not required when working with anonymised patients records in the THIN database.
: The author declares that they have no competing interests.
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