Table 1.

Exclusion and inclusion criteria

	Inclusion criteria	Exclusion criteria
Study design	Title or abstract must mention measles or measles vaccination.	Studies published before 2011.
	Title or abstract must mention ‘vaccine uptake’, ‘attitudes’, ‘acceptance’, ‘hesitancy’, or ‘refusal’.	Studies not in English.
	Primary data.	Secondary data.
	Focus groups, in-depth interviews, questionnaires, and surveys.	Purely quantitative data.
Study population	Parental population group.	Study population of only children, adolescents, healthcare workers, or students.
	Studies conducted only in Europe.	Studies conducted outside Europe.
Research topic	Studies focusing on attitudes or beliefs about measles vaccine.	Studies focusing primarily on effectiveness of interventions, epidemiological mapping, or serological research.