Annelotte van Bommel

168 Figure 1. Outer circle; the Plan Do Check Act cycle on a national level using clinical audit data for improvement of breast cancer care. The interplay between clinicians and the other stakeholders in the management of the NBCA comes with challenges inherent to the differing perspectives of all participants. The common goal of quality assurance through consistent measurement is evidently acknowledged by all. Yet, while most clinicians strive for optimal outcomes in their individual institutions and acknowledge a reduction in undesirable hospital variation is an important goal, patients and insurance companies at the same time may assign value to observed differences between institutions. They seek discriminative information to identify best practices for their treatment or purchasing for contracting institutions. This “constructive friction” has hitherto strengthened the NBCA. Interpreting NBCA results Once quality is unambiguously defined, and a standard of care is translated into a quality indicator with a norm, NBCA results reflect valid and valuable time trends in the delivered breast cancer care in the Netherlands and identify those