The objective of this study is to evaluate the impact of the value-based formulary on patient out-of-pocket spending and health plan spending as well as the impact of the value-based formulary on medication use, emergency department visits, hospitalizations, and outpatient office visits.

Inclusion Criteria:

• Individuals:

  • aged 0-64

  • Continuously enrolled in an employer-sponsored health plan for at least 12 months (with one-month allowable gap) prior to the index date

    • For individuals in the exposed group, the index date is defined as the start date of value-based formulary implementation at the employer group level
    • For individuals in the control group, the index date is defined as the index date of the matched exposed individual

• Employer groups:

  • that transition to the value-based formulary if they transitioned all enrollees in that employer group (no individual selection)

Exclusion Criteria:

- Individuals with:

• missing gender information
• missing zip code level demographics at all member months

All individuals who satisfy the eligibility criteria are included.

Individual participant data will not be made available per data use agreement.