Sukuba Abbiyesuku, Gogo James Owo
Aims: The study aims to determine the prevalence of iron deficiency anaemia and evaluate biochemical predictors among secondary school girls in Rivers State, Nigeria. Study Design: A school-based cross-sectional analytical study. Place and Duration of Study: Selected secondary schools in Rivers State, Nigeria, during the study period. Methodology: A total of 250 secondary school girls aged 10–19 years were selected using a multistage sampling technique. Data were collected using a structured interviewer-administered questionnaire. Venous blood samples were analysed for haemoglobin, serum ferritin, serum iron, and total iron-binding capacity. Data were analysed using descriptive statistics, an independent-samples t-test, Pearson’s correlation, and binary logistic regression, with statistical significance set at p < 0.05. Results: The prevalence of iron deficiency anaemia was 24.8%. Participants with iron deficiency anaemia had significantly lower haemoglobin, serum ferritin, and serum iron concentrations, but higher total iron-binding capacity, than those without iron deficiency anaemia (p < 0.001). Haemoglobin, serum ferritin, and serum iron were negatively correlated with iron deficiency anaemia, whereas total iron-binding capacity was positively correlated with the condition (p < 0.001). Binary logistic regression identified serum ferritin as the strongest independent predictor (adjusted OR = 0.173; 95% CI: 0.079–0.361; p < 0.001). Conclusion: Serum ferritin, interpreted alongside haemoglobin, serum iron, and TIBC, may support the identification of iron deficiency anaemia among secondary school girls. The findings support school-based screening and context-appropriate preventive interventions, including nutrition education, iron supplementation, and malaria prevention.