The U.S. Department of Health and Human Services Office of Inspector General determined that Wisconsin made at least $18.5 million in improper fee-for-service Medicaid payments for Applied Behavior Analysis services in 2021 and 2022. The findings, detailed in audit report A-06-23-01002, reveal a systemic breakdown in how the state oversees Medicaid-funded autism therapy for children.
Wisconsin’s payments for ABA did not fully comply with federal and state requirements. All 100 sampled enrollee-months included payments for one or more claim lines that were improper or potentially improper.
The scale of the problem could be far larger. The OIG estimates potentially improper payments could amount to around $94.3 million, with $62.3 million of that from the federal share.
The primary cause of improper payments was session notes that didn’t support the billed CPT codes. The second most significant reason for improper payments was that session notes didn’t support the number of units billed.
Auditors also found that providers were billing for time that went unaccounted for. The majority of session notes for the sampled enrollee-months documented that ABA time was billed continuously without any adjustment to the units of service for potential non-therapy times, such as meals.
In some cases, session documentation failed to show any meaningful clinical activity. One session note stated that the child “participated in social group during session and discrete trial was not conducted – no modifications needed at this time” and indicated that no direction was given to a technician.
The OIG recommended that the Wisconsin Department of Health Services refund $12,287,252 — the federal share — to the federal government for fee-for-service Medicaid ABA payments that did not comply with federal and state requirements. (RELATED: Wisconsin Lawmakers Speak Out on the Death of Iran’s Former Supreme Leader)
The OIG also recommended that Wisconsin exercise reasonable diligence to review and determine whether any of the estimated $62,334,835 in potentially improper ABA payments complied with federal and state requirements, and refund the federal share of any improper payment amount to the federal government.
Beyond repayment, auditors laid out a series of corrective actions. The OIG recommended that the state provide ABA providers with more guidance about the proper way to document services, develop a procedure to verify providers and their specialty level, and conduct periodic statewide reviews of Medicaid ABA payments.
Wisconsin is not alone. In December 2024, HHS OIG released one of the most important ABA Medicaid audit reports to date, revealing $56.5 million in improper payments to ABA providers in Indiana. HHS OIG announced in 2022 it would conduct reviews of Medicaid payments to ABA providers in seven states.
A 2022 investigation found that a rapid influx of private equity investment in the industry has contributed to a crisis of providers routinely overbilling insurers while providing substandard treatment to vulnerable children and families. (RELATED: Vice President J.D. Vance Campaigns in Wisconsin to Boost Van Orden, Tiffany)
These OIG audit reports reflect heightened federal scrutiny of Medicaid ABA billing and documentation compliance, and will likely prompt increased scrutiny by state Medicaid agencies to preemptively address the potential federal share of the repayments identified as part of the audits.
