Methods
A protocol paper detailing the methods for this systemic review and meta-analysis have been previously published(9). Our systematic review protocol was submitted to the International Prospective Register of Systematic Reviews (PROSPERO) on the 20th of April 2020 and accepted on the 6th July 2020 (registration number CRD42020177386). We have presented the data using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement(10), the Meta-Analyses of Observational Studies checklist (MOOSE)(11) and the Cochrane Handbook for Systematic Reviews of Interventions(12).  Information regarding registration can be accessed from http://www.crd.york.ac.uk/PROSPERO.
Eligibility Criteria:
Eligibility of studies included in this systematic review was based on pre-planned inclusion and exclusion criteria applied to each of the following domains: participant, exposure, comparator, study type and outcome.