Footnotes

• Twitter @mariapsebastian

• Contributors MPS conceived the idea, performed the literature search, wrote the manuscript draft and is the guarantor. SLD contributed to drafting of the manuscript, edited the draft and performed a critical review of the manuscript. OAU critically reviewed the manuscript.

• 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.