Impact of changing provider remuneration on NHS general dental practitioner services in Northern Ireland: a mixed-methods study

Background: Policy-makers wanted to reform the NHS dental contract in Northern Ireland to contain costs, secure access and incentivise prevention and quality. A pilot project was undertaken to remunerate general dental practitioners using a capitation-based payment system rather than the existing fee-for-service system. Objective: To investigate the impact of this change in remuneration. Design: Mixed-methods design using a difference-in-difference evaluation of clinical activity levels, a questionnaire of patient-rated outcomes and qualitative assessment of general dental practitioners’ and patients’ views. Setting: NHS dental practices in Northern Ireland. Participants: General dental practitioners and patients in 11 intervention practices and 18 control practices. Interventions: Change from fee for service to a capitation-based system for 1 year and then reversion back to fee for service. Main outcome measures: Access to care, activity levels, service mix and financial impact, and patient-rated outcomes of care. Results: The difference-in-difference analyses showed significant and rapid changes in the patterns of care provided by general dental practitioners to patients (compared with the control practices) when they moved from a fee-for-service system to a capitation-based remuneration system. The number of registered patients in the intervention practices compared with the control practices showed a small but statistically significant increase during the capitation period (p