References

Adamu, Abdu A., Olalekan A. Uthman, Muktar A. Gadanya, and Charles S. Wiysonge. 2019. “Implementation and Evaluation of a Collaborative Quality Improvement Program to Improve Immunization Rate and Reduce Missed Opportunities for Vaccination in Primary Health-Care Facilities: A Time Series Study in Kano, Nigeria.” Expert Review of Vaccines 18 (9): 969–91. https://doi.org/10.1080/14760584.2019.1647782.
Aheto, Justice Moses K., Iyanuloluwa Deborah Olowe, Ho Man Theophilus Chan, Adachi Ekeh, Boubacar Dieng, Biyi Fafunmi, Hamidreza Setayesh, et al. 2023. “Geospatial Analyses of Recent Household Surveys to Assess Changes in the Distribution of Zero-Dose Children and Their Associated Factors Before and During the COVID-19 Pandemic in Nigeria.” Vaccines 11 (12): 1830. https://doi.org/10.3390/vaccines11121830.
Bates, Douglas, Martin Maechler, Ben Bolker, and Steven Walker. 2025. Lme4: Linear Mixed-Effects Models Using Eigen and S4. https://github.com/lme4/lme4/.
Beaumont, Jean-François, and Nelson Émond. 2022. “A Bootstrap Variance Estimation Method for Multistage Sampling and Two-Phase Sampling When Poisson Sampling Is Used at the Second Phase.” Stats 5 (2): 339–57. https://doi.org/10.3390/stats5020019.
Bednarczyk, Robert A, Kyra A Hester, Sameer M Dixit, Anna S Ellis, Cam Escoffery, William Kilembe, Katie Micek, Zoë M Sakas, Moussa Sarr, and Matthew C Freeman. 2022. “Exemplars in Vaccine Delivery Protocol: A Case-Study-Based Identification and Evaluation of Critical Factors in Achieving High and Sustained Childhood Immunisation Coverage in Selected Low-Income and Lower-Middle-Income Countries.” BMJ Open 12 (4): e058321. https://doi.org/10.1136/bmjopen-2021-058321.
Bell, James, Belinda Lartey, Marcos Fernandez, Natasha Darrell, Holly Exton-Smith, Cassie Gardner, Emily Richards, et al. 2023. “A Structural Equation Modelling Approach to Understanding the Determinants of Childhood Vaccination in Nigeria, Uganda and Guinea.” Edited by Abram L. Wagner. PLOS Global Public Health 3 (3): e0001289. https://doi.org/10.1371/journal.pgph.0001289.
Bell, James, Belinda Lartey, Gemma Spickernell, Natasha Darrell, Frances Salt, Cassie Gardner, Emily Richards, et al. 2022. “Applying a Social-Ecological Model to Understand Factors Impacting Demand for Childhood Vaccinations in Nigeria, Uganda, and Guinea.” SSM - Qualitative Research in Health 2 (December): 100180. https://doi.org/10.1016/j.ssmqr.2022.100180.
Benjamini, Yoav, and Yosef Hochberg. 1995. “Controlling the False Discovery Rate: A Practical and Powerful Approach to Multiple Testing.” Journal of the Royal Statistical Society: Series B (Methodological) 57 (1): 289–300.
Bosch-Capblanch, Xavier, K. Banerjee, and A. Burton. 2012. “Unvaccinated Children in Years of Increasing Coverage: How Many and Who Are They? Evidence from 96 Low- and Middle-Income Countries.” Tropical Medicine & International Health 17 (6): 697–710. https://doi.org/10.1111/j.1365-3156.2012.02989.x.
Carter, Austin, Nadia Akseer, Kevin Ho, Oliver Rothschild, Niranjan Bose, Agnes Binagwaho, Lisa R Hirschhorn, et al. 2020. “A Framework for Identifying and Learning from Countries That Demonstrated Exemplary Performance in Improving Health Outcomes and Systems.” BMJ Global Health 5 (12): e002938. https://doi.org/10.1136/bmjgh-2020-002938.
Center for International Earth Science Information Network (CIESIN), Columbia University. 2024. GRID3 NGA - Settlement Extents v3.1.” New York: GRID3. https://doi.org/10.7916/x9xg-e262.
Cooper, Chelsea M., Rebecca Fields, Corinne I. Mazzeo, Nyapu Taylor, Anne Pfitzer, Mary Momolu, and Cuallau Jabbeh-Howe. 2015. “Successful Proof of Concept of Family Planning and Immunization Integration in Liberia.” Global Health: Science and Practice 3 (1): 71–84. https://doi.org/10.9745/GHSP-D-14-00156.
Dimitrova, Anna, Gabriel Carrasco-Escobar, Robin Richardson, and Tarik Benmarhnia. 2023. “Essential Childhood Immunization in 43 Low- and Middle-Income Countries: Analysis of Spatial Trends and Socioeconomic Inequalities in Vaccine Coverage.” PLOS Medicine 20 (1): e1004166. https://doi.org/10.1371/journal.pmed.1004166.
Dooley, Claire. 2019. gridEZ: Algorithm for Generating Enumeration Zones.” https://github.com/cadooley/gridEZ.
Eti, Eno-Obong, Angela Odiachi, Leanne Dougherty, Matthew Alabi, Adetayo Adetunji, and Adebola Adedimeji. 2024. Everything Created by a White Man Is for Pagans: Understanding the Barriers to Childhood Immunization in North-Eastern and North-Western Nigeria.” medRxiv. https://doi.org/10.1101/2024.03.29.24305068.
Etim, E. E., A. Odiachi, L. Dougherty, M. Alabi, A. Adetunji, and A. Adedimeji. 2025. “Understanding Caregivers’ and Community Influencers’ Perspectives on the Barriers to Childhood Immunisation in Northern Nigerian States with Public-Private Partnerships in Routine Immunisation Programme.” BMC Public Health 25 (1): 1471. https://doi.org/10.1186/s12889-025-22710-7.
Eze, G. U., and O. O. Adeleye. 2015. “Enhancing Routine Immunization Performance Using Innovative Technology in an Urban Area of Nigeria.” West African Journal of Medicine 34 (1): 3–10.
Federal Ministry of Health and Social Welfare of Nigeria (FMoHSW), National Population Commission (NPC) [Nigeria], and ICF. 2025. “Nigeria Demographic and Health Survey 2024.” DHS Final Report. Abuja, Nigeria,; Rockville, Maryland, USA: FMoHSW, NPC,; ICF. https://dhsprogram.com/publications/publication-FR395-DHS-Final-Reports.cfm.
Fleck, Fiona. 2004. “Nigerian State of Kano Resumes Polio Vaccination.” BMJ 328 (7453): 1515. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC449847/.
Florczyk, Aneta J., Christina Corbane, Daniele Ehrlich, Sergio Freire, Thomas Kemper, Lorenzo Maffenini, Michele Melchiorri, et al. 2019. GHS Settlement Model grid (GHS‑SMOD), Global Human Settlement Layer Data Package 2019 (GHS P2019).” EUR 29788 EN (JRC 117104). European Commission, Joint Research Centre (JRC). https://doi.org/10.2760/290498.
FMoHSW, NPC, and ICF. 2024. “Nigeria Demographic and Health Survey 2023–24: Key Indicators Report.” Abuja, Nigeria,; Rockville, Maryland, USA: Federal Ministry of Health and Social Welfare of Nigeria (FMoHSW); National Population Commission (NPC) [Nigeria]; ICF.
Gavi. 2023. “Nigeria Country Profile.” 2023. https://zdlh.gavi.org/country-profiles/nigeria#background.
———. 2025. “Zero-Dose Children and Missed Communities.” 2025. https://www.gavi.org/our-alliance/strategy/phase-5-2021-2025/equity-goal/zero-dose-children-missed-communities.
Gavi Zero-Dose Learning Hub. 2023. “Nigeria Zero-Dose Situation Analysis.” https://zdlh.gavi.org/.
Ibekwe, Jonas Lotanna, Victor Oluwafemi Femi-Lawal, Jolly Akor Thomas, Faith Uzoamaka Okei, Moses Ojomakpenen Ojile, and Oluwatobiloba Oladipupo Akingbulugbe. 2024. “Nigerians’ Attitudes and Perceptions Towards Vaccine Acceptance During and After the COVID-19 Pandemic.” Journal of Medicine, Surgery, and Public Health 2: 100066. https://doi.org/10.1016/j.glmedi.2024.100066.
Ibraheem, Rasheedat, Moshood Akintola, Mohammed Abdulkadir, Hafsat Ameen, Oladimeji Bolarinwa, and Muhammed Adeboye. 2021. “Effects of Call Reminders, Short Message Services (SMS) Reminders, and SMS Immunization Facts on Childhood Routine Vaccination Timing and Completion in Ilorin, Nigeria.” African Health Sciences 21 (2): 951–59. https://doi.org/10.4314/ahs.v21i2.57.
Ibrahim, Aminu Abdullahi. 2025. “Kano Tops Nigeria’s Zero-Dose Immunization List as Boost Project Targets Urgent Action.” April 12, 2025. https://kanofocus.com/2025/04/12/kano-tops-nigerias-zero-dose-immunization-list-as-boost-project-targets-urgent-action/.
IHME. 2023. GBD Results.” Institute for Health Metrics and Evaluation (IHME). 2023. https://vizhub.healthdata.org/gbd-results/.
———. 2024. “Vaccine Coverage.” Institute for Health Metrics and Evaluation (IHME). 2024. https://www.healthdata.org/research-analysis/health-topics/vaccine-coverage.
Jacobson Vann, Julie C., Robert M. Jacobson, Tamera Coyne-Beasley, Josephine K. Asafu-Adjei, and Peter G. Szilagyi. 2018. “Patient Reminder and Recall Interventions to Improve Immunization Rates.” Cochrane Database of Systematic Reviews, no. 1: CD003941. https://doi.org/10.1002/14651858.CD003941.pub3.
Jean Baptiste, A. E., J. Wagai, S. Hahné, A. Adeniran, R. I. Koko, S. de Vos, M. Shibeshi, E. A. M. Sanders, B. Masresha, and E. Hak. 2024. “High-Resolution Geospatial Mapping of Zero-Dose and Underimmunized Children Following Nigeria’s 2021 Multiple Indicator Cluster Survey/National Immunization Coverage Survey.” Journal of Infectious Diseases 230 (1): e131–38. https://doi.org/10.1093/infdis/jiad476.
Kano State Ministry of Health. 2014. “Appendix B.2: Estimated Immunization Coverage, Dropout, and Design Effects Among Children 12–23 Months, by LGA.”
Kazi, Muhammad Ahmed, Sajid Bashir Soofi, Imtiaz Hussain, Masawar Hussain, Muhammad Umer, Ahmad Khan, Khalid Feroz, et al. 2024. 2023 Supplementary Immunization Coverage Survey in Super High Risk Union Councils of Pakistan (TPVICS-SHRUCs Rounds 1–3). Aga Khan University; Survey Report. Book 3. https://ecommons.aku.edu/pakistan_coe-wch_survey_report/3.
Kish, Leslie. 1965. Survey Sampling. New York: John Wiley & Sons.
Korn, Edward L, and Barry I Graubard. 1998. “Confidence Intervals for Proportions with Small Expected Number of Positive Counts Estimated from Survey Data.” Survey Methodology 24: 193–201.
LaFond, Anne, Natasha Kanagat, Robert Steinglass, Rebecca Fields, Jenny Sequeira, and Sangeeta Mookherji. 2015. “Drivers of Routine Immunization Coverage Improvement in Africa: Findings from District-Level Case Studies.” Health Policy and Planning 30 (3): 298–308. https://doi.org/10.1093/heapol/czu011.
Lakens, Daniël, Anne M. Scheel, and Peder M. Isager. 2018. “Equivalence Testing for Psychological Research: A Tutorial.” Advances in Methods and Practices in Psychological Science 1 (2): 259–69. https://doi.org/10.1177/2515245918770963.
Lumley, Thomas, Peter Gao, and Ben Schneider. 2024. Survey: Analysis of Complex Survey Samples. http://r-survey.r-forge.r-project.org/survey/.
Mahachi, Kurayi, Joss Kessels, Kofi Boateng, Anne Eudes Jean Baptiste, Pamela Mitula, Ebru Ekeman, Laura Nic Lochlainn, et al. 2022. “Zero- or Missed-Dose Children in Nigeria: Contributing Factors and Interventions to Overcome Immunization Service Delivery Challenges.” Vaccine 40 (37): 5433–44. https://doi.org/10.1016/j.vaccine.2022.07.058.
Mindset. 2026. “Methods for Estimating Vaccination Coverage and Zero-Dose Prevalence: Head-to-Head Comparison Report.” Mindset. https://zd-head2head.netlify.app/.
Nigeria country-wide operational ward boundaries (administrative level 3), v1.0.” 2024. GRID3. https://data.grid3.org/datasets/GRID3::grid3-nga-operational-wards-v1-0/about.
NPC, and ICF. 2019. “Nigeria Demographic and Health Survey 2018.” Abuja, Nigeria,; Rockville, Maryland, USA: National Population Commission (NPC) [Nigeria]; ICF.
NPHCDA. 2021. “Nigeria Strategy for Immunisation and PHC System Strengthening Version 2.0 (2021–2024): A Companion Document to Nigeria Strategy for Immunisation and PHC System Strengthening [NSIPSS 2018–2028].” National Primary Health Care Development Agency (NPHCDA).
Ophori, Endurance A., Festus A. Tula, Omoyibo E. Azih, Elimian E. Okojie, and Benson F. Ikpo. 2014. “Current Trends of Immunization in Nigeria: Prospect and Challenges.” Tropical Medicine and Health 42 (2): 67–75. https://www.jstage.jst.go.jp/article/tmh/42/2/42_2013-13/_article.
Oyo-Ita, Angela E., Patrick Hanlon, Ogonna Nwankwo, Xavier Bosch-Capblanch, Dachi Arikpo, Ekperonne Esu, Christian Auer, and Martin Meremikwu. 2021. “Cost-Effectiveness Analysis of an Intervention Project Engaging Traditional and Religious Leaders to Improve Uptake of Childhood Immunization in Southern Nigeria.” PLOS ONE 16 (9): e0257277. https://doi.org/10.1371/journal.pone.0257277.
Oyo-Ita, Angela, Xavier Bosch-Capblanch, Amanda Ross, Afiong Oku, Ekpereonne Esu, Soter Ameh, Olabisi Oduwole, Dachi Arikpo, and Martin Meremikwu. 2021. “Effects of Engaging Communities in Decision-Making and Action Through Traditional and Religious Leaders on Vaccination Coverage in Cross River State, Nigeria: A Cluster-Randomised Control Trial.” PLOS ONE 16 (4): e0248236. https://doi.org/10.1371/journal.pone.0248236.
Ozigbu, Chamberline E., Bankole Olatosi, Zhenlong Li, James W. Hardin, and Nicole L. Hair. 2022. “Correlates of Zero-Dose Vaccination Status Among Children Aged 12–59 Months in Sub-Saharan Africa: A Multilevel Analysis of Individual and Contextual Factors.” Vaccines 10 (7): 1052. https://doi.org/10.3390/vaccines10071052.
Parker, JDTM, Makram Talih, Donald J Malec, Vladislav Beresovsky, Margaret D Carroll, Joe Fred Gonzalez, Brady E Hamilton, et al. 2017. “National Center for Health Statistics Data Presentation Standards for Proportions.”
Pathways. n.d. “Segmentation.” n.d. https://www.projectpathways.org/segmentation.
Pesaresi, Martino, Marcello Schiavina, Panagiotis Politis, Sergio Freire, Kai Goch, Jürgen H. Uhl, Alessandro Carioli, et al. 2023. GHS‑BUILT‑C R2023A: Morphological Settlement Zone (MSZ) dataset.” European Commission, Joint Research Centre (JRC). https://data.europa.eu/89h/3c60ddf6-0586-4190-854b-f6aa0edc2a30.
Phillips, David E, Joseph L Dieleman, Stephen S Lim, and Jessica Shearer. 2017. “Determinants of Effective Vaccine Coverage in Low and Middle-Income Countries: A Systematic Review and Interpretive Synthesis.” BMC Health Services Research 17 (1): 681. https://doi.org/10.1186/s12913-017-2626-0.
Rhoda, Dale. 2021. Vaccination coverage quality indicators (VCQI): A flexible collection of Stata programs for standardized survey data analysis.” 2021 Stata Conference 32. Stata Users Group. https://ideas.repec.org/p/boc/scon21/32.html.
Rutstein, Shea Oscar. 2008. “Data Reduction Using Principal Component Analysis.” Calverton, Maryland, USA: ICF International. https://dhsprogram.com/publications/publication-mr6-methodological-reports.cfm.
———. 2015. “Steps to Constructing the New DHS Wealth Index.” Rockville, Maryland, USA: ICF International. https://dhsprogram.com/publications/publication-mn9-methodological-notes.cfm.
Rutstein, Shea Oscar, and Kiersten Johnson. 2004. “The DHS Wealth Index.” DHS Comparative Reports No. 6. Calverton, Maryland, USA: ORC Macro, MEASURE DHS+. https://dhsprogram.com/publications/publication-cr6-comparative-reports.cfm.
Sato, Ryoko. 2023. “Zero-Dose, Under-Immunized, and Dropout Children in Nigeria: The Trend and Its Contributing Factors over Time.” Vaccines 11 (1): 181. https://doi.org/10.3390/vaccines11010181.
Sbarra, A. N., S. Rolfe, J. Q. Nguyen, L. Earl, N. C. Galles, A. Marks, et al. 2021. “Mapping Routine Measles Vaccination in Low- and Middle-Income Countries.” Nature 589 (7842): 415–19. https://doi.org/10.1038/s41586-020-03043-4.
Schneider, Ben. 2025. Svrep: Tools for Creating, Updating, and Analyzing Survey Replicate Weights. https://bschneidr.github.io/svrep/.
Sirko, Wojciech, Sergey Kashubin, Marvin Ritter, Alfred Annkah, Yacine S. E. Bouchareb, Yann Dauphin, Daniel Keysers, Mark Neumann, Moustapha Cisse, and John A. Quinn. 2021. “Continental-Scale Building Detection from High Resolution Satellite Imagery.” https://arxiv.org/abs/2107.12283.
Thomson, Dana R. 2022. Designing and Implementing Gridded Population Surveys. Edited by Dale A. Rhoda. Boston, MA: Dana Thomson Consulting. https://gridpopsurvey.com/wp-content/uploads/2024/05/Designing_and_Implementing_Gridded_Population_Surveys_2022a.pdf.
Tillé, Yves. 1996. “An Elimination Procedure of Unequal Probability Sampling Without Replacement.” Biometrika 83 (2): 238–41.
UN. n.d. Goal 3: Ensure healthy lives and promote well-being for all at all ages.” n.d. https://sdgs.un.org/goals/goal3.
UNICEF. 2025. “Under-Five Mortality.” 2025. https://data.unicef.org/topic/child-survival/under-five-mortality/.
UNICEF. n.d. “Nigeria Immunization Schedule.” Accessed July 6, 2025. https://www.unicef.org/nigeria/documents/nigeria-immunization-schedule.
Utazi, C. Edson, Justice M. K. Aheto, Adelle Wigley, Natalia Tejedor-Garavito, Amy Bonnie, Christopher C. Nnanatu, John Wagai, et al. 2023. “Mapping the Distribution of Zero-Dose Children to Assess the Performance of Vaccine Delivery Strategies and Their Relationships with Measles Incidence in Nigeria.” Vaccine 41 (1): 170–81. https://doi.org/10.1016/j.vaccine.2022.11.026.
Utazi, C. Edson, Iyanuloluwa D. Olowe, H. M. Theophilus Chan, Winfred Dotse-Gborgbortsi, John Wagai, Jamila A. Umar, Sulaiman Etamesor, et al. 2024. “Geospatial Variation in Vaccination Coverage and Zero-Dose Prevalence at the District, Ward and Health Facility Levels Before and After a Measles Vaccination Campaign in Nigeria.” Vaccines 12 (12): 1299. https://doi.org/10.3390/vaccines12121299.
Utazi, C. E., J. Thorley, V. A. Alegana, et al. 2019. “Mapping Vaccination Coverage to Explore the Effects of Delivery Mechanisms and Inform Vaccination Strategies.” Nature Communications 10: 1633. https://doi.org/10.1038/s41467-019-09611-1.
Utazi, C. E., J. Thorley, V. A. Alegana, M. J. Ferrari, S. Takahashi, C. J. E. Metcalf, J. Lessler, and A. J. Tatem. 2018. “High Resolution Age-Structured Mapping of Childhood Vaccination Coverage in Low and Middle Income Countries.” Vaccine 36 (12): 1583–91. https://doi.org/10.1016/j.vaccine.2018.02.020.
Vaccine Impact Modelling Consortium. 2021. “Estimating the Health Impact of Vaccination Against Ten Pathogens in 98 Low‑income and Middle‑income Countries from 2000 to 2030: A Modelling Study.” The Lancet 397 (10272): 398–408. https://doi.org/10.1016/S0140-6736(20)32657-X.
Wagai, John Ndegwa, Dale Rhoda, Mary Prier, Mary Kay Trimmer, Caitlin B. Clary, Joseph Oteri, Bassey Okposen, Adeyemi Adeniran, Carolina Danovaro-Holliday, and Felicity Cutts. 2021. “Implementing WHO Guidance on Conducting and Analysing Vaccination Coverage Cluster Surveys: Two Examples from Nigeria.” PLOS ONE 16 (2): e0247415. https://doi.org/10.1371/journal.pone.0247415.
WHO. n.d. IA2030 IG 2.1: Number of Zero Dose Children.” n.d. https://www.who.int/data/gho/indicator-metadata-registry/imr-details/7792.
———. n.d. Immunization Agenda 2030.” n.d. https://www.immunizationagenda2030.org/.
WHO. 2018. Vaccination Coverage Cluster Surveys: Reference Manual. Geneva: World Health Organization. https://www.who.int/publications/i/item/WHO-IVB-18.09.
WHO Regional Office for Africa. 2019. “NERICC: Nigeria’s Panacea for Routine Immunization and Primary Health Care Strengthening.” 2019. https://www.afro.who.int/news/nericc-nigerias-panacea-routine-immunization-and-primary-health-care-strengthening.
WHO, and UNICEF. 2022. “WUENIC—World Health Organization/UNICEF Estimates of National Immunization Coverage.” 2022. https://immunizationdata.who.int/.
Wonodi, C., and B. A. Farrenkopf. 2023. “Defining the Zero Dose Child: A Comparative Analysis of Two Approaches and Their Impact on Assessing the Zero Dose Burden and Vulnerability Profiles Across 82 Low- and Middle-Income Countries.” Vaccines 11 (10): 1543. https://doi.org/10.3390/vaccines11101543.