Funding for this research was provided by:
Medical Research Council (MR/N013700/1, MR/N013700/1)
Text and Data Mining valid from 2018-11-05
Received: 20 March 2018
Accepted: 21 September 2018
First Online: 5 November 2018
Ethics approval and consent to participate
: Parents/legal guardians provided written informed consent. Ethical approval for the original collection of data was obtained by ethics committees in India, Japan and the UK for each country’s data collection separately.
: Not applicable.
: The authors declare that they have no competing interests.
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