Introduction: Anaemia among children is an issue of significant concern within the realm of public health due to its potential to result in significant adverse outcomes, including cognitive deficits and growth deficiencies. Its prevalence exhibits regional variations, wherein larger frequencies are observed in regions characterized by lower levels of socioeconomic development. This study sought to identify the individual, household, and contextual factors associated with anaemia in Nigeria. Methods: Data on a weighted sample of 11,223 children under five years of age from 42,000 households was obtained from the Nigeria Demographic and Health Survey (NDHS) 2018. The study utilized the household members recode file, a data base which allows for the estimation of prevalence of childhood anaemia together with selected household variables and the kids recode file, a data base that allows for estimation of other household variables. Relevant variables were then generated, and the two data files were merged. Descriptive statistics were generated, and the multi-level logistic regression was computed to identify individual, household and contextual factors associated with anaemia. Results: The study found that the overall prevalence of anaemia was 67.9%. It was noted that being a: child of Muslim parents; big baby at birth; wasted, stunted; underweight, child resident in Southeast and Southwest Nigeria and a child resident in rural area were significantly associated with increased odds of anaemia . While having a mother with secondary education, being a child in the second, third, or fourth birth order belonging to richest households, living in households with tiled floors, living in households with cemented floors, living in households with carpeted floors and improved sanitation/water source and living in Northeast Nigeria were significantly associated with decreased odds of anaemia. About 8.5% of individual, household and contextual factors determine the average prevalence of anaemia in children in Nigeria. Conclusion: The findings from this study reveal that individual, household and contextual factors are important determinants of anaemia in children in Nigeria.

Tukur Dahiru the first author of this manuscript is a DHS fellow he is affiliated with the Nigeria DHS program and contributed to the NDHS 2018 report while all other authors have no competing interest to declare.

This study did not receive any funding

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Ethical approval was not obtained for this manuscript as it involves secondary analysis of anonymized data already in the public domain. However, the National Health Research Ethics Committee of Nigeria (NHREC) and the International Cooperation and Family (ICF) Institutional Review Boards reviewed and approved the original survey protocol before the survey was conducted.

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