Funding for this research was provided by:
Medical Research Council (MM_UU_12013/6, 102215/2/13/2)
Wellcome Trust (102215/2/13/2, 105612/Z/14/Z)
University of Bristol (105612/Z/14/Z)
Elizabeth Blackwell Institute for Health Research (105612/Z/14/Z)
Received: 27 April 2018
Accepted: 13 December 2018
First Online: 17 January 2019
Ethics approval and consent to participate
: Ethics approval for the study was obtained from the ALSPAC Ethics and Law Committee and the Local Research Ethics Committee (NHS North Somerset & South Bristol Research Ethics Committee). Full details of ethics committee approval references for ALSPAC can be found online (ExternalRef removed/). This study was approved by the ALSPAC Executive Committee. Study participants who complete questionnaires consent to the use of their data by approved researchers. Up until age 18 an overarching parental consent was used to indicate parents were happy for their child (the study participant) to take part in ALSPAC. Consent for data collection and use was implied via the written completion and return of questionnaires. Study participants have the right to withdraw their consent for specific elements of the study, or from the study as a whole, at any time.
: JK reports personal fees from Actelion Pharmaceuticals, outside the submitted work; CJ reports grants from Elizabeth Blackwell Institute, during the conduct of the study. SG, RC, MM, PE, AJ, FH, NW and KT have nothing to disclose.
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