Effect of eliminating behavioral health benefits for selected medicaid enrollees.
OBJECTIVE
To determine the extent to which the elimination of behavioral health benefits for selected beneficiaries of Oregon's Medicaid program affected general medical expenditures among enrollees using outpatient mental health and substance abuse treatment services.


METHODS
Twelve months of claims before and 12 months following a 2003 policy change, which included the elimination of the behavioral health benefit for selected Oregon Medicaid enrollees.


METHODS
We use a difference-in-differences approach to estimate the change in general medical expenditures following the 2003 policy change. We compare two methodological approaches: regression with propensity score weighting; and one-to-one covariate matching.


RESULTS
Enrollees who had accessed the substance abuse treatment benefit demonstrated substantial and statistically significant increases in expenditures. Individuals who accessed the outpatient mental health benefit demonstrated a decrease or no change in expenditures, depending on model specification.


CONCLUSIONS
Elimination of the substance abuse benefit led to increased medical expenditures, although this offset was still smaller than the total cost of the benefit. In contrast, individuals who accessed the outpatient mental health benefit did not exhibit a similar increase, although these individuals did not include a portion of the Medicaid population with severe mental illnesses.
McConnell
K John
KJ
Center for Policy and Research in Emergency Medicine, Department of Emergency Medicine, Oregon Health & Science University, Mail Code CR114, 3181 SW Sam Jackson Park Rd, Portland OR 97239-3098, USA. mcconnjo@ohsu.edu
Wallace
Neal T
NT
Gallia
Charles A
CA
Smith
Jeanene A
JA
D000553:Ambulatory Care / Q000191:economics; D001524:Behavioral Medicine / Q000191:economics* / Q000706:statistics & numerical data; D005500:Follow-Up Studies; D017048:Health Care Costs / Q000706:statistics & numerical data*; D005102:Health Expenditures / Q000706:statistics & numerical data*; D006302:Health Services Research; D006801:Humans; D019458:Insurance Coverage; D008484:Medicaid / Q000191:economics* / Q000706:statistics & numerical data; D008605:Mental Health Services / Q000191:economics* / Q000706:statistics & numerical data; D009922:Oregon; D010045:Outpatients; D012720:Severity of Illness Index; D019966:Substance-Related Disorders / Q000191:economics*; D016896:Treatment Outcome; D014481:United States