Evaluation of value-based insurance design for primary care.

Objectives: To evaluate the impact of value-based insurance design (VBID), which removed patient cost sharing for primary care visits, on healthcare spending in a large, geographically diverse employer.

Study Design: Quasi-experimental, difference-in-differences (DID) design, administrative claims-based study.

Methods: Healthcare spending during the preintervention period (2008 and 2009) was compared with the postintervention period (2011 through 2014) to measure the impact of removing primary care cost sharing.