Programme of Diabetes Education in the City of Corrientes (PRODIACOR): Clinical, Metabolic and Economic Outcomes of a Prospective-randomized Trial Based on Different Patient-centered Educational Strategies for People With Type 2 Diabetes

The study protocol was evaluated and approved by an external ethical committee; patients gave informed consent to participate in the study according with the guidelines from the International Conference on Harmonisation and WHO good clinical practice standards. The study design has been previously described in detail.30 Briefly, the investigators implemented a randomized 2x2 design to address the effectiveness of different education strategies involving the health provider and people with diabetes).

Sample size: for its determination in each of the four groups, the investigators considered the change in haemoglobin A1c (from baseline to the end of the study) as the primary outcome variable. This was done using a two-sided test at the 5% level of significance and 80% power using a paired t-test. The sample size was increased by 25% to account for non-independence and dropout, resulting in the number of providers and patients listed in table 1.

Educational strategies The investigators used the Diabetes Training Course for Physicians and Diabetes Structured Education Courses for People with T2DM, whose characteristics and usefulness have been previously reported.

Data collection Patients' clinical, psychological, biochemical, therapeutic and economic data before and after PRODIACOR were recorded using the Physician Data Form, the Annual and Bi-annual Clinical Record Form and the Feedback Report Form. The investigators developed software that compares the first two mentioned forms and generates a Biannual Feedback Report for physicians and patients; it compares the values recorded for haemoglobin A1c, serum lipids and blood pressure, and the goal proposed for each parameter according to international standards. It also includes recommendations about appropriate treatment to achieve therapeutic goals.31 Additionally, the investigators used the Patient Questionnaire, based on the one previously used in the Diabetes Advantage Program (DAP) which includes questions about the disease, and the WHO-5 well-being questionnaire. Data collection was completed with the Personalized Checkbook, a tool initially developed for the PROPAT study, whose aim and content have been previously described. It serves to order procedures, consultations, laboratory tests, prescription of drugs and strips for glucose self-monitoring, to record and communicate results, and as a payment voucher for all those items.

Study and Data management The Local Coordinator (city of Corrientes) together with the Central Cordinating Center (CENEXA), oversaw the education courses and the overall trial and maintained periodic contact with the participating physicians. Performance of the physicians and their patients was monitored at regular intervals (6 months) during the whole study period. Every physician was visited twice a year by a physician monitor who assessed the quality of the data he has recorded.30 Participating physicians collect their own patients´ data, sent it to the Local Coordinator who controlled its completeness and forwarded to the Central Coordinating Centre.