Footnotes

• Contributors AHS: Protocol writing, Conception, Writing—Original draft. JB: Software, Writing—Original Draft and Reviewing. AK: Data extraction, Writing—Original Draft. IBY: Data Extraction, Writing—Original Draft. SS: Writing—Original Draft and Reviewing, Illustration/Figure, Manuscript Proofing. YK: Software, Writing—Original Draft and Reviewing. HA: Writing—Original Draft and Reviewing. AG: Conception, Methodology, Supervision, Writing—Reviewing.

• Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

• Competing interests None declared.

• Provenance and peer review Not commissioned; internally peer reviewed.