Table 1

Eligibility criteria following the PICOS scheme18

ParticipantsAll types of participantsNone
InterventionThe Global Solar UV Index (introduced in 1995 by the WHO and partner organisations)Other versions of UV indices
  • Quantitative ‘status quo’ estimates (including baseline data of intervention studies) of

    • Awareness of the UV index

    • Understanding of the UV index

    • Use of the UV index

Other outcomes
Study design
  • Experimental studies

    • Randomised controlled trials

    • Others

  • Observational studies

    • Before-and-after studies with and without controls

    • Case–control studies

    • Prospective and retrospective cohort studies

    • (Repeated) cross-sectional studies

Qualitative studies
  • N/A, not applicable; UV, ultraviolet.