Summary of findings for the main comparison. Health education compared to usual practice.

Comparison 1: health education compared to usual practice
Population: adolescents and parents Setting: Sweden and USA intervention: health education Comparison: usual practice
Outcomes	Impact				№ of participants (studies)	Certainty of the evidence (GRADE)**
	Absolute effects* (95% CI)		Relative effect (95% CI)	Narrative results
	With usual practice	With health education
Uptake of HPV vaccinea	209 per 1000	298 per 1000 (242 to 367)	RR 1.43 (1.16 to 1.76)	Health education improves uptake of HPV vaccine compared to usual practice.	1054 (3)b	⊕⊕⊕⊕ Highc,d,e
CI: confidence interval; HPV: human papillomavirus; RR: risk ratio. *The anticipated absolute effect in the intervention group (and its 95% confidence interval) is based on the assumed likelihood of being vaccinated in the usual care group and the relative effect of the intervention (and its 95% CI). **GRADE Working Group grades of evidence.: High certainty: this research provides a very good indication of the likely effect. The likelihood that the effect will be substantially different† is low. Moderate certainty: this research provides a good indication of the likely effect. The likelihood that the effect will be substantially different† is moderate. Low certainty: this research provides some indication of the likely effect. However, the likelihood that it will be substantially different† is high. Very low certainty: this research does not provide a reliable indication of the likely effect. The likelihood that the effect will be substantially different† is very high. †Substantially different = a large enough difference that it might affect a decision.

^a The lag‐time between delivery of the intervention and assessment of outcomes ranged from three months (Grandahl 2016) to 11 months (Winer 2016 )

^bDiclemente 2015 (randomised trial); Grandahl 2016 (cluster‐randomised trial); Winer 2016 (cluster‐randomised trial).
 ^c Well conducted randomised trials with consistent findings (I² = 0%).

^d The findings from the one non‐randomised trial that assessed this comparison were similar to the findings of the randomised trials.

^eOne study reported that health education did not have any adverse events in relation to usual practice (Rickert 2015).