Table 4.

Highest and lowest performing individual ads by topic and framing

Topic	Highest performing framing	Headline	CTR (%)	Lowest performing framing	Headline	CTR (%)
COVID-19 general	Descriptive	WHO Official Updates: Coronavirus Disease 2020	22.4	Loss	Don’t miss new updates | WHO Official coronavirus info	6.4
COVID-19 vaccines	Descriptive	Official Updates | COVID-19 vaccine updates	17.2	Loss	Don’t miss anything | Coronavirus vaccine updates	3.0
Masks	Appeals to values	Protect each other | Wear a mask. Fight coronavirus	13.4	Emphasising reasons	See how to wear a mask safely | Wear a mask. Fight coronavirus	2.6
Vaccines general	Descriptive	Vaccines are safe | Protect against disease	8.8	Collective	2–3 million lives saved yearly | Get vaccinated	4.0

CTR, click-through rate.