title: Incomplete childhood immunization in Nigeria: a multilevel analysis of individual and contextual factors.
abstract: Under-five mortality remains high in sub-Saharan Africa despite global decline. One quarter of these deaths are preventable through interventions such as immunization. The aim of this study was to examine the independent effects of individual-, community- and state-level factors on incomplete childhood immunization in Nigeria, which is one of the 10 countries where most of the incompletely immunised children in the world live.
  
  
  
  The study was based on secondary analyses of cross-sectional data from the 2013 Nigeria Demographic and Health Survey (DHS). Multilevel multivariable logistic regression models were applied to the data on 5,754 children aged 12-23 months who were fully immunized or not (level 1), nested within 896 communities (level 2) from 37 states (level 3).
  
  
  
  More than three-quarter of the children (76.3%) were not completely immunized. About 83% of children of young mothers (15-24 years) and 94% of those whose mothers are illiterate did not receive full immunization. In the fully adjusted model, the chances of not being fully immunized reduced for children whose mothers attended antenatal clinic (adjusted odds ratio [aOR] = 0.49; 95% credible interval [CrI] = 0.39-0.60), delivered in health facility (aOR = 0.62; 95% CrI = 0.51-0.74) and lived in urban area (aOR = 0.66; 95% CrI = 0.50-0.82). Children whose mothers had difficulty getting to health facility (aOR = 1.28; 95% CrI = 1.02-1.57) and lived in socioeconomically disadvantaged communities (aOR = 2.93; 95% CrI = 1.60-4.71) and states (aOR = 2.69; 955 CrI =1.37-4.73) were more likely to be incompletely immunized.
  
  
  
  This study has revealed that the risk of children being incompletely immunized in Nigeria was influenced by not only individual factors but also community- and state-level factors. Interventions to improve child immunization uptake should take into consideration these contextual characteristics.
authors.affiliation: Warwick-Centre for Applied Health Research and Delivery (WCAHRD), Division of Health Sciences, University of Warwick Medical School, Coventry, UK. s.adedokun@warwick.ac.uk.|Department of Demography and Social Statistics, Obafemi Awolowo University, Ile-Ife, Nigeria. s.adedokun@warwick.ac.uk.
authors.forename: Sulaimon T
authors.initials: ST
authors.lastname: Adedokun
authors.affiliation: Warwick-Centre for Applied Health Research and Delivery (WCAHRD), Division of Health Sciences, University of Warwick Medical School, Coventry, UK.|Centre for Evidence-based Health Care, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
authors.forename: Olalekan A
authors.initials: OA
authors.lastname: Uthman
authors.affiliation: NIHR Collaboration for Leadership in Applied Health Research and Care, West Midlands (CLAHRC WM), University of Warwick Medical School, Coventry, UK.
authors.forename: Victor T
authors.initials: VT
authors.lastname: Adekanmbi
authors.affiliation: Centre for Evidence-based Health Care, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.|South African Cochrane Centre, South African Medical Research Council, Cape Town, South Africa.
authors.forename: Charles S
authors.initials: CS
authors.lastname: Wiysonge
mesh_terms: D000293:Adolescent; D003430:Cross-Sectional Studies; D003710:Demography; D005260:Female; D057220:Health Literacy / Q000706:statistics & numerical data; D006297:Health Services Accessibility / Q000706:statistics & numerical data*; D006306:Health Surveys; D006801:Humans; D007114:Immunization / Q000523:psychology / Q000706:statistics & numerical data*; D017589:Immunization Programs / Q000706:statistics & numerical data*; D007223:Infant; D016015:Logistic Models; D008297:Male; D009035:Mothers / Q000523:psychology / Q000706:statistics & numerical data*; D055361:Multilevel Analysis; D009549:Nigeria; D016017:Odds Ratio; D011295:Prenatal Care / Q000706:statistics & numerical data; D012111:Residence Characteristics / Q000706:statistics & numerical data; D055815:Young Adult
keywords: Children; Contextual; Factors; Immunization; Incomplete; Model; Multilevel