Footnotes

• Contributors All authors contributed equally to the planning and completion of this 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 DM is the CEO and TYW is a cofounder of the health technology company, Plano Pte Ltd, Singapore, which develops software solutions and applications for monitoring vision and smart device screen time usage.

• Patient consent None declared.

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