Funding for this research was provided by:
Research Trainees Coordinating Centre (ICA-CDRF-2016-02-014)
Received: 16 January 2018
Accepted: 19 June 2018
First Online: 18 July 2018
: LB is a research dietitian at the NIHR Bristol Biomedical Research Centre—Nutrition Theme. All co-authors are members of either the NIHR Bristol Biomedical Research Centre—Nutrition Theme or the CF Specialist Centre at the Bristol Royal Hospital for Children. FL is a senior research associate and dietitian. SLH is a consultant in Paediatric Respiratory Medicine. KH is a paediatric CF dietitian. JHS is a professor of Diabetes and Metabolic Endocrinology. RP is a systematic reviewer.
: Not applicable as this is a systematic review of completed studies.
: Not applicable
: The authors declare that they have no competing interests.
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