Implementation of altered provider incentives for a more individual-risk-based assignment of dental recall intervals: evidence from a health systems reform in Denmark.

Equipping health systems with suitable incentives for efficient resource allocation remains a major health policy challenge. This study examines the impacts of 2015 regulatory changes in Danish dental care which aimed at effectuating a transition from six-to-twelve-monthly dental recall intervals, for every patient, towards a model where patients with higher need receive dental recalls systematically more frequently than patients with lower need. Exploiting administrative data from the years 2012-2016 from the Danish National Health Insurance database containing 72,155,539 treatment claims for 3,759,721 unique patients, we estimated a series of interrupted time-series regression models with patient-level fixed-effects. In comparison to the pre-reform period, the proportion of patients with recall intervals of up to 6 months was by 1.2%-points larger post-implementation; that of patients with 6-12-monthly recalls increased by 0.7%-points; that of patients with more than 12-monthly dental recalls decreased by 1.9%-points. The composition of care shifted more substantially: the proportion of treatment sessions including preventive care increased by 31.5%-points (95%-CI: 31.4;31.6); that of sessions including scaling increased by 24.1%-points (24.0;24.2); that of sessions including diagnostics decreased by 34.5%-points (34.4;34.6). These findings suggest that dental care providers may have responded differently to regulatory changes than intended by the health policy.