The Choice of Renal Replacement Therapy (CORETH) project: study design and methods

BACKGROUND: To date, research has neglected the patient's psychosocial and cognitive conditions as contributing factors to dialysis modality decision-making. Hence, the Choice of Renal Replacement Therapy (CORETH) study aims to examine these conditions with regard to their impact on the choice. Here we describe the design of the multicentre study, which is supported by a grant from the German Ministry for Education and Research. METHODS: Two groups of patients will be compared after having chosen peritoneal or haemodialysis as permanent treatment. About 1200 participants from 50 dialysis centres all over Germany will be questioned. The questionnaire addresses social, psychological and shared decision-making aspects. Furthermore, cognitive functioning will be tested. For an economic evaluation direct and indirect costs of treatment will be calculated. Changes will be examined through a one-year follow-up. CONCLUSIONS: The results will enlighten the treatment choice under the German healthcare system. They will provide further insight regarding the discussion on patient autonomy. From the patients' perspective, the results will help to strengthen their participation in the individual process of health-related decision-making.