Schwarz 2008.

Methods	Randomised trial conducted in the USA
Participants	Participants: adolescents (girls and boys) and caregivers Number per group: 37 caregivers and 41 adolescents aged 10–18 years in intervention group and 39 caregivers and 39 adolescents aged 10–18 years in control group Total number enrolled: 328 children and 170 caregivers Study population: homeless shelter children and adolescents and their caregivers
Interventions	Intervention: hepatitis B education intervention Description: the videos were "Respect Yourself/Protect Yourself" by the Hepatitis Foundation International (to instruct the person about hepatitis B infection and the importance of hepatitis B vaccine). The interventions included: health education, cash incentives, and free vaccination. 1 of the interventions was health education on hepatitis B vaccine for caregivers and adolescents. The caregivers and adolescents were exposed to an educational video called "Respect Yourself/Protect Yourself" which educated the participants about hepatitis B infection and the importance of hepatitis B vaccination. After the video presentation, the research nurse reviewed the contents of the video with a 5‐minute PowerPoint summary and encouraged the participants to ask questions to increase their understanding of the information presented. The families were given the vaccine information sheet for hepatitis B. Thereafter, free vaccination was offered as an incentive. The investigators offered free hepatitis B vaccine, provided caregivers with USD 10, and gave adolescents and caregivers gift packages containing cosmetics for the adults and sweets and toothbrushes for the children. All families were instructed to return after 1 month for the second visit (second dose), and after 2 months for a third dose. During the second visit, the caregivers were paid USD 10 and during the third visit they were paid USD 30 and adolescents and caregivers were given gift packages for both visits. Duration: 21 months Comparison 1: usual practice Description of comparison 1: education about the deleterious health consequences of cigarette smoking. Vaccine target: hepatitis B Disease targeted: hepatitis B Number of doses: 3 doses
Outcomes	Hepatitis B vaccine uptake Hepatitis B knowledge score
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No description.
Allocation concealment (selection bias)	Unclear risk	No description.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	The outcome is an objective measure.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	The outcome is an objective measure.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No loss to follow‐up.
Selective reporting (reporting bias)	Low risk	Study was free from selective outcome reporting.
Other bias	Low risk	No evidence of other bias.