Abstract Background: Childhood immunization is one of the most successful public health interventions that prevent children’s morbidity and mortality from Vaccine Preventable Diseases (VPDs). Despite this, achieving high vaccination coverage is still one of the pressing public health problems globally, particularly in low-and middle-income countries. Objective: This study aims to identify factors associated with non- and incomplete vaccination status among children aged 12-23 months in Gindhir rural district, East Bale zone, Southeast Ethiopia. Methods: A cross-sectional study supplemented with a qualitative study was conducted in the Gindhir district from April 25-June10/ 2021. A total of 563 mothers of children 12-23 months participated. Study participants were selected using computer-generated random numbers.  The sample was proportionally allocated to the size of children 12-23 months in each kebele. An administered structured questionnaire was used to collect data using face-to-face interviews. Epi–data version 3.1 was used for data entry and SPSS version 25 software was used for data analysis. Bivariate and Multinomial logistic regression analysis was used to identify the determinants of vaccination status at a P value of less than 0.05. Seven in-depth interviews and two focused group discussions were conducted and analyzed manually by coding. Results: - Totally 563 mothers/caregivers with children aged 12-23 months participated with a 96.6% response rate. Of the 563 children included in the study, 307 (54.5% [95%CI: 50.1-58.8]) were fully vaccinated, 142(25.5% [95%CI:21.7-29.1]) were incompletely vaccinated and 114 (20.2% [95%CI: 16.7-23.8]) were not vaccinated at all. Home delivery [3.46 (95%CI: 1.27-9.40)], absence of nearby health facility[4.84(95% CI: 1.75-13.39)], lack of transportation incur cost [2.75(95%CI:1.06-7.14)], mothers/caregivers negative perceived benefits of child vaccination [2.69(95%CI: 1.35-5.37)], mothers/caregivers poor knowledge about VPDs [2.78(95%CI: 1.14-5.30)] and vaccination schedule [5.54(95%CI: 2.74-11.22)], and negative attitude towards vaccination[2.01(95%CI: 1.01-3.98)] were identified as independent predictors of non-vaccination. While home delivery [6.85 (95%CI: 1.69-27.79)], lack of provision of counselling by health workers [2.19(95%CI: 1.13-4.27)], mothers/caregivers’ poor knowledge about VPDs [2.71(95%CI: 1.60-4.58)] and vaccination schedule [3.30(95%CI: 1.90-5.74)], and attitude towards vaccination [2.53(95%CI: 1.47-3.38)] were significantly associated with incomplete vaccination status. Conclusion: Designing and implementing public health interventions tailored to locally identified problems is vital to narrow the observed variation in childhood vaccination status.

The authors have declared no competing interest.

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This study is not funded by government or other funders

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Ethical approval was obtained from Jimma University's ethical review committee with committee's reference number IRB-00018/2020 submitted to the East Bale Zone Health Department. An official support letter was written by the Zonal Health Department and given to the Gindhir Health office. After explaining the study’s purpose, procedure, potential benefits and risks, and their right to participate or not, written informed consent was obtained from mother / care giver of the study participants. Data were collected anonymously information obtained from study participants was used for study purposes only and not disclosed to ensure confidentiality. Those mothers/caretakers with children vaccination status non-and incompletely vaccinated were advised to vaccinate their children. Furthermore, general information on the importance of child vaccination was provided for mothers/caregivers with children of non-and incomplete vaccination

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