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Association of Participation in a Value-Based Insurance Design Program With Health Care Spending and Utilization
Hui Zhang1,2, David W Cowling2
1Now with Medicare and Duals Analytic Unit, California Department of Health Care Services, Sacramento.
Importance:
Value-based insurance design (VBID) has mostly been used in improving medication use and adherence for certain conditions or patients, but its outcomes remain uncertain when applied to other services and to all health plan enrollees.
Objective:
To determine the association of participation in a California Public Employees' Retirement System (CalPERS) VBID program with its enrollees' health care spending and utilization.
Design, Setting, And Participants:
A retrospective cohort study with difference-in-differences propensity-weighted 2-part regression models was performed in 2021 to 2022. A VBID cohort was compared with a non-VBID cohort both before and after VBID implementation in California in 2019 with 2 years' follow-up. The study sample included CalPERS preferred provider organization continuous enrollees from 2017 through 2020. Data were analyzed from September 2021 to August 2022.
Exposures:
The key VBID interventions include (1) if selecting and using a primary care physician (PCP) for routine care, PCP office visit copayment is $10 (otherwise, PCP office visit copayment is $35 as for specialist visit); and (2) annual deductibles reduced by a half through completion of the following 5 activities: annual biometric screening, influenza vaccine, nonsmoking certification, second opinion for elective surgical procedures, and disease management participation.
Main Outcomes And Measures:
The primary outcome measures included annual per member total approved payments for multiple inpatient and outpatient services.
Results:
The 2 compared cohorts of 94 127 participants (48 770 were female [52%]; 47 390 were younger than 45 years old [50%]) had insignificant baseline differences after propensity-weighting adjustment. The VBID cohort had significantly lower probabilities of inpatient admissions (adjusted relative odds ratio [OR], 0.82; 95% CI, 0.71-0.95), and higher probabilities of receiving immunizations (adjusted relative OR, 1.07; 95% CI, 1.01-1.21) in 2019. Among those with positive payments, VBID was associated with higher mean total allowed amounts for PCP visits in 2019 and 2020 (adjusted relative payments ratio, 1.05; 95% CI, 1.02-1.08). There were no significant differences for inpatient and outpatient combined totals in 2019 and 2020.
Conclusions And Relevance:
The CalPERS VBID program achieved desired goals for some interventions with no added total costs in its first 2 years of operation. VBID may be used to promote valued services while containing costs for all enrollees.
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