CoDiab-VD: a Population-based Cohort on Quality of Care of Patients With Diabetes in the Canton of Vaud (Switzerland)

Diabetes, one of the most prevalent chronic disease (~ 9% worldwide), represents a major public health burden in terms of morbidity, disability and mortality. Caring for patients with diabetes requires effective collaboration between healthcare providers, teamwork, self-management education and use of evidence-based medicine. However, these processes of care are complex and often suboptimal. Improving quality of diabetes care is thus needed to reduce the health and societal burden of this disease.

In the canton of Vaud, a state in Switzerland with more than 700,000 inhabitants, a recent population-based study has shown that the prevalence of diabetes was around 7%. Data on the quality of diabetes care is scarce and quality of care data are still infrequently and unsystematically collected in Switzerland. In addition, when data are available, they focus on intermediate outcomes as well as clinical and biological cardiovascular risk factors. Population-based data on patient-reported outcomes are not considered.

In 2010, the Public Health Department of the canton of Vaud initiated the development of a regional diabetes program entitled "Programme cantonal Diabète" (PcD). It aimed both at decreasing the incidence of diabetes and improving care for patients with diabetes.

To tailor the program to the healthcare needs of patients and healthcare professionals involved in diabetes care, an exploratory study using qualitative methods was conducted in 2010. This was followed by a population-based survey conducted in fall 2011 and summer 2012. The objectives of the survey were to characterize patients with diabetes and assess the quality of the care they received. In addition, the results of the survey were used to help targeting unmet needs and possible areas of improvements, and constituted the patients' baseline measurement for the evaluation of the PcD.

The CoDiab-VD cohort emerged from that initial project; its specific objectives were 1) to follow over time the quality of diabetes care, 2) to explore topics that the PcD needed for its development, 3) to assess the impact of the PcD on the care of patients with diabetes, and 4) to evaluate the coverage of the PcD in the canton of Vaud.