Abstract

Type 1 diabetes mellitus is a chronic autoimmune disorder characterized by destruction of pancreatic β-cells and the need for lifelong insulin replacement. Safe insulin self-administration requires adolescents to understand dose preparation, injection technique, insulin storage, and routine monitoring. Aim: To assess adolescents’ knowledge of insulin self-administration and determine whether a structured instructional program improves knowledge over time. Methods: A quasi-experimental, two-group study was conducted at the Diabetic and Endocrine Center in Al-Hilla City. A total of 120 adolescents were assessed using a structured questionnaire at baseline (pre-test), post-test I, and post-test II between May 17, 2025 and October 4, 2025. Results: The intervention group demonstrated a marked increase in mean knowledge scores from pre-test to post-test I, with a slight decline at post-test II, whereas the control group showed minimal change over the same period. Repeated-measures analysis showed significant effects of Time, Group, and Time × Group, with large effect sizes. Conclusion: A structured instructional program significantly improved adolescents’ knowledge of insulin self-administration and showed evidence of knowledge retention over follow-up.