Iodine concentration level of iodized dietary salt and its associated factors: a systematic review and meta-analysis

BACKGROUND: Iodine deficiency disorder (IDD) is a major public health problem in Ethiopia. The availability of adequate iodized dietary salt at the household level is immensely important. Hence, this review aimed to estimate the pooled prevalence of adequate iodine concentration level of iodized dietary salt at the household level and its associated factors in Ethiopia. METHODS: We searched the literature using electronic databases (PubMed/Medline, Google Scholar, Science Direct, and Embase) and gray literature from January 9, 2022, to February 25, 2022. The rapid test kit was used to measure the adequacy of iodine level of dietary salt. The quality of studies was assessed using Joanna Briggs Institute critical appraisal tool. Heterogeneity between studies was checked using I(2) test statistics and publication bias was checked using funnel plot and Egger’s statistical test at a 5% significance level. A random-effects model was employed to estimate the pooled prevalence of the outcome variable and its determinants in Ethiopia. RESULTS: The search identified 149 studies of which 18 studies were included with a total of 10,556 participants. The pooled prevalence of adequate iodine levels of iodized salt in Ethiopia was 44.37% (95% CI: 35.85-52.88). Women who had formal education (adjusted odds ratio (AOR) = 1.99 (95% CI: 1.47–2.48)), good knowledge of women (AOR = 2.14, 95% CI: 1.36–3.36), packed iodized salt (AOR = 3.85 (95% CI: 1.88–7.87)) and storage of iodized salt at home for less than 2 months (AOR = 2.66 (95% CI: 2.11–3.35) were the significant factors. CONCLUSION: This review suggests that the pooled prevalence of adequate iodine levels was low. Our finding highlights the need for considering the educational status, knowledge, and duration of salt storage to enhance the prevalence of adequate levels of iodized salt at the national level.