Largest Study of High-Deductible Health Plans Finds Substantial Cost Savings, but Less Preventive Care
Mar 24, 2011
Published in: The American Journal of Managed Care, v. 17, no. 3, Mar. 2011, p. 222-230
Posted on RAND.org on February 28, 2011
OBJECTIVE: To investigate the effects of high-deductible health plans (HDHPs) and consumer-directed health plans (CDHPs) on healthcare spending and on the use of recommended preventive care. STUDY DESIGN: Retrospective study. METHODS: We analyzed claims and enrollment data for 808,707 households from 53 large US employers, 28 of which offered HDHPs or CDHPs. We estimated the effects of HDHP or CDHP enrollment on healthcare cost growth between 2004 and 2005 using a difference-in-difference method that compared cost growth for families who were enrolled in HDHPs or CDHPs for the first time in 2005 with cost growth for families who were not offered HDHPs or CDHPs. Control families were weighted using propensity score weights to match the treatment families. Using similar methods, we examined the effects of HDHP or CDHP enrollment on the use of preventive care and the effects of HDHP or CDHP offering by employers on the mean cost growth. RESULTS: Families enrolling in HDHPs or CDHPs for the first time spent 14% less than similar families enrolled in conventional plans. Families in firms offering an HDHP or a CDHP spent less than those in other firms. Significant savings for enrollees were realized only for plans with deductibles of at least $1000, and savings decreased with generous employer contributions to healthcare accounts. Enrollment in HDHPs or CDHPs was also associated with moderate reductions in the use of preventive care. CONCLUSIONS: The HDHPs or CDHPs with at least a $1000 deductible significantly reduced healthcare spending, but they also reduced the use of preventive care in the first year. This merits additional study because of concerns about enrollee health.