Table 4.

Themes that emerged promoting MMR vaccine hesitancy or refusal

Themes	Sub-themes	Studies
Vaccine factors	Fear of vaccine side effects	2–9, 13, 15, 17, 19, 20
	Doubts of vaccine safety	2, 3, 6, 7, 9–12, 14
	High risk compared to benefit from vaccine	7–9, 12, 13, 15, 17, 18
	Experience (self/peers) of vaccine side effects	2, 4, 5, 9, 11, 14, 18
	Vaccination given too young	2, 3, 7–9, 15, 18
	Fear of combined vaccines	7, 11, 15, 18, 19
	Immune overloading	2, 7, 8, 12
	Doubts of vaccine efficacy	2, 8, 12, 17
	Fear of vaccine constituents	2, 7, 10, 14
	Intrusion/invasive procedure	8, 15, 18, 20
	Doubts of necessity of vaccine	7, 12
	Family history of autism	19
Measles factors	Lack of severity of measles	4, 5, 7–9, 13–15, 18, 20
	Perceived low susceptibility to measles	4, 5, 8, 9, 15
	Measles helps child development	3, 8, 19
	Competence to cope with measles	3
Trust factors	Mistrust in healthcare workers/experts/government	2, 3, 5, 6, 10, 11, 18, 19
	Bad experience/relationship/communication with healthcare workers	9, 10, 13, 14, 18
	Fear of commercial motivation	2, 7, 20
Social factors	Natural immunity preferred	2, 3, 5, 8, 12, 19, 20
	Alternative medicine preferred	3, 12–14
	Right to autonomous decision	3, 5, 16, 18
	Healthy lifestyle measures are sufficient to treat/prevent	2, 5, 7, 8
	Decision requires more time	3, 6
	Disease is a natural part of life	3
	Fear of judgement from peers	9
Practical factors	Contradictions to vaccination	7, 14–16, 18
	Access to clinics	15, 16, 18
	Temporary residence	14, 15, 18
	Forgetfulness	7, 14, 15
	Competing priorities	15, 18
	Cost of individual vaccine	15, 18
	Did not receive timely vaccination invitation	1, 7
	Vaccine not offered	14
Knowledge factors	Insufficient information	2, 7, 9, 10, 13, 14, 16, 18
	Misinformation online/media	11, 14, 16, 18, 19
	Lack competence to make decision	5, 6
	Discordant information	7, 10
	Lay knowledge from family/peers	15, 20
	Advised against/cautioned by healthcare provider	7, 11