Substitution or addition: An observational study of a new primary care initiative in the Netherlands.

The introduction of the PC+ model in one region in the Netherlands was associated with an increase in the use of low-complex specialised care. This suggests that the ability of the PC+ model to substitute for specialist care at population level may be limited. Going forward, it will be important to continue monitoring and evaluating service use as substitution effects may materialise only over a longer timeframe.