Objective: To determine the effectiveness of an educational program for the control of glycatedhemoglobin (HbA1c) in patients with diabetes. Materials and methods: A before-and-after cohortstudy was conducted in patients with diabetes. Participants received an educational interventionconsisting of individualized monthly medical care by a family doctor and educational sessions bythe nursing staff over a six-month period. Follow-up was performed with a multidisciplinary team,with timely referrals to secondary care in ophthalmology, endocrinology and internal medicine,based on the specific needs of each patient. To ensure the temporal effect of the intervention inrelation to the impact on HbA1c, it was measured before and after the educational interventionfollowing the 2020 American Diabetes Association (ADA) Standards of Medical Care in Diabetes.Patients with normal HbA1c levels were exclu...