Footnotes

• Contributors SEC conceived the idea for the article. The literature search was performed jointly between all authors. CB wrote the introduction section, along with regular reviewing of each draft of the article. AH wrote the administration section of the article along with regular reviewing of each draft of the article. SEC wrote the other sections of the article. NAK substantially reviewed the article, rewriting parts of some sections. SEC is the guarantor of the article.

• Funding None.

• Competing interests None.

• Provenance and peer review Commissioned; externally peer reviewed.