Table 2.

Summary of included secondary analyses

Variables	Group	Total (N = 116)
		N	%
Publication metric
Publish time period	2006–2011	26	22.4
	2012- August 2018	90	77.6
Country of affiliationsa	High income	80	68.9
	Low-middle income	36	31.0
Country analyzed	Multiple countries	37	31.9
	Single country	79	68.1
Affiliations match with survey countriesb	Yes	38	48.1
	No	41	51.9
Survey year (last year)	before 2011	84	72.4
	2012–2018	32	27.6
Publication delay	Mean (SD)	5.4 (2.6)
	Within 5 years	66	56.9
	More than 5 years	50	43.1
Analyses content
Survey types	DHS	100	86.2
	MICS	7	6.0
	Both	9	7.8
Outcomes	Specific immunization	55	41.7
	Complete/full immunization	53	40.2
	Partial or incomplete immunization	12	9.4
	Never vaccinated	11	8.3
	Otherc	1	0.8
Type of analysis	Factors associated	77	55.4
	Inequalities	21	15.1
	Timeliness	12	8.6
	Trends	16	11.5
	Others	13	9.4
Proxies for “quality”
How persons without documented vaccination were handled	Caregiver recall used	86	74.1
	Recall excluded	12	10.3
	Not mentioned	17	14.6
	From other sourcesd	1	0.9
Percentage of documented vaccination seen	Mentioned	36	31.0
	No mentioned	80	69.0
Weighted analysis	Yes	67	57.8
	No	4	3.4
	Not mentioned	45	38.8
Potential survey biases	Listed	54	46.6
	Not listed	62	53.4
Limitation(s) of secondary analyses	Listed	89	76.7
	Not listed	27	23.3

^aThe affiliations of first and corresponding authors separately counted; most of them (110/116) were from the same affiliation or income-level country. For those with first and corresponding author had a different affiliation (6/116), the higher income-level was used for classification

^bOnly secondary analyses using survey data from single country are included here (i.e., multi-country analyses exclude from this row)

^cThe one outcome listed as “other” was on knowledge about Human Papilloma Virus (HPV) vaccine

^dInformation from administrative activities (e.g., vaccination records kept by health facilities), censuses, and vital registration systems was referred