Table 4.

Results of country-level determinants analysis of the proportion of zero-dose children reached with supplementary immunization activities.

Variable	Coefficient	Standard error	Regression p-value	Correlation coefficient	Correlation p-value
Constant	1.078	0.287	0.01	N/A	N/A
Routine measles immunization coverage	−0.004	0.005	0.46	−0.495	0.06
Gross domestic product per capita	0.001	0.001	0.91	−0.210	0.45
Population density	−0.001	0.001	0.68	−0.310	0.26
Percent of urban population	−0.004	0.006	0.54	−0.417	0.12
Health care expenditure per capita	0.002	0.005	0.79	−0.255	0.36
WHO Africa region fixed effect	(reference)
WHO Americas region fixed effect	−0.083	0.195	0.69	N/A	N/A
WHO Southeast Asia region fixed effect	0.331	0.258	0.25	N/A	N/A
Low-income country fixed effect	(reference)
Lower middle-income country fixed effect	−0.113	0.179	0.55	N/A	N/A

WHO = World Health Organization. A full list of countries by WHO region is included in the supplementary appendix (Table A).

Note: “Zero-dose children” are defined as children with no previous history of measles vaccination.