['Assessment of effects on quality of care, in terms of patient outcomes, when tasks in the care for outpatients with stable type 2 diabetes are transferred from internist to nurse specialist and from outpatient clinic to general practice.', 'For the management of chronic diseases with a high prevalence and requiring current monitoring, it is suggested that substitution of care may be an appropriate solution to safeguard high quality care.', 'A 12-month nonequivalent control group design was used. General practitioners (GPs) referring diabetes patients to the University Hospital Maastricht were asked to choose for the traditional model or the nurse specialist model. Informed consent was obtained from patients with stable diabetes type 2 attending these practices. All patients received care according to the model chosen by their GP. Identified outcomes were: clinical status, health status, self-care behaviour, knowledge of diabetes, patient satisfaction, and consultation with care-providers.', 'In the control group (n=47) no patients were treated with oral hypoglycaemic agents (OHA) only. The control group was compared with an intervention subgroup (n=52) also without patients receiving OHA only. Clinical data were available for all patients. Patients without complete data from questionnaires had better mean concentration of HbA1c than patients with complete data (P=0.004). The traditional care model and the nurse specialist model achieved equal outcomes, while glycaemic control of patients in the nurse specialist model improved (from 8.6% to 8.3%) but deteriorated in the traditional model (from 8.6% to 8.8%; P-value between groups=0.001).'] Is substitution model with central role for nurse specialist justified in the care for stable type 2 diabetic outpatients?