Key Takeaways
- The audits are documentation audits, not clinical audits: OIG findings turn on whether session notes, signatures, credentials, and treatment plans support what was billed. The clinical question of whether ABA was medically necessary was never reviewed.
- Code mismatches are the most common improper payment finding: Auditors flagged 97153 (one-on-one direct treatment) billed when documented activities suggested 97154 (group), and 97155 (protocol modification) billed when the activity was assessment or parent training.
- Time billing requires actual time, not scheduled time: Sessions billed in fixed nine-to-twelve and twelve-to-three blocks were flagged as inconsistent with how real-world ABA unfolds. Documentation must reflect when services actually started and stopped.
- Protocol modification means modification: If a code requires evidence of an adapted or updated treatment protocol, generic notes such as “I updated these programs” do not satisfy the requirement. The note must describe what was modified, or, where the qualified healthcare professional evaluated the protocol and determined modification was not necessary, the specific procedural changes that were considered and the reasoning for not modifying.
- Continuous high-intensity sessions raise red flags: Auditors questioned seven-and-a-half and eight-hour blocks billed without documented breaks for meals or rest. Records indicating children napping during sessions billed at high intensity were called out specifically.
- Concurrent billing requires its own documentation: Even when co-treatment with speech or occupational therapy was approved during prior authorization, most session notes failed to describe what the ABA team did during the overlapping window to support the other service.
- The Colorado paradox is a warning to every state: Colorado’s audit flagged 97156 family guidance services that the state required clinically but did not allow providers to bill. Mismatches between policy expectation and fee schedule reality create improper payment exposure on both sides of the contract.
The headline numbers from the U.S. Department of Health and Human Services Office of Inspector General’s ABA audits get the attention. Indiana, $56 million in improper payments. Wisconsin, $18.5 million. Maine, $45.6 million. Colorado, $77.8 million.
Together, more than $123 million in federal recoupment recommendations and another roughly $400 million in potentially improper payments. The presenters at the Council of Autism Service Providers’ 2026 conference represented three coalition organizations: Mariel Fernandez of CASP, Chanti Fritzsching Waters of the Association of Professional Behavior Analysts (APBA), and Andi Waks and Jenna Minton of ProActive Strategies and the ABA Coding Coalition. As they walked an audience of clinic owners through the documentation findings, the underlying pattern was consistent: the audits are not clinical reviews. They are operational reviews of session notes, signatures, credentials, and code-to-activity alignment. “The risk wasn’t primarily clinical,” one presenter put it. “It was operational.”
The broader audit cascade now reshaping ABA is anchored in this distinction. What follows is the documentation patterns the OIG flagged, organized around the specific CPT codes where auditors found improper or potentially improper payments.
97153 Versus 97154: When Direct Treatment Notes Describe Group Activities
CPT code 97153 covers adaptive behavior treatment delivered one-on-one by a behavior technician. CPT code 97154 covers group adaptive behavior treatment by a technician. The codes pay at different rates and are not interchangeable. Auditors found a recurring mismatch: providers billed 97153 in cases where session notes described group activities, peer interactions, or shared activities that fit 97154’s group definition. In other instances, the activities were narrated in ways that left it unclear whether other clients were present, and the OIG flagged the ambiguity itself as a documentation deficiency. The practical implication is that a session note must establish whether the session was individual or group, and the billed code must reflect that. Where peers are present, each technician must make it clear in the note that they were providing a 1:1 service with peers present. If a single technician provides services to two or more peers at the same time, that is a group service and must be documented and billed under 97154. If a technician’s note describes the same activity another technician’s note describes for a different client at the same time, that pattern raises the inference that the service was group, not individual.
97155: Protocol Modification Means Modification, and It Is Not Assessment or Parent Training
CPT code 97155 covers adaptive behavior treatment with protocol modification, delivered by a qualified healthcare professional. Auditors found two distinct misuses. The first was billing the code for activities the code does not cover: assessment time (which has its own code, 97151) and parent training time (which has its own code, 97156). The second was billing 97155 without documenting the protocol modification the code requires. “You can’t just say I updated these programs,” one CASP presenter said, paraphrasing the OIG’s reading. “You need to talk about what you did.”
There is a parallel question about whether protocol modification requires an actual modification at all. The original intent of the code, per the ABA Coding Coalition that wrote it, was to capture face-to-face direction by a qualified professional whose role includes the discretion to modify if needed, whether or not a modification was made on a given date. Some payers read the code that way. Others, including several state Medicaid agencies, read it more strictly: no documented modification, no billable 97155. Providers should know which reading their specific payer applies. Where a payer reads the code strictly, the absence of a documented modification converts the claim into an improper payment.
Time Billing: Actual Time, Not Scheduled Time
ABA CPT codes are billed in 15-minute units. Per AMA guidance, a unit is attained when the midpoint of the interval is passed: eight or more accumulated minutes earns one 15-minute unit. Auditors found a recurring pattern of session notes that did not document when a service started or ended, only that it was scheduled within a particular window. Providers billed fixed blocks: nine to twelve, twelve to three. “Unless you’re maybe running training schedules,” one presenter observed, “people don’t show up at exactly the same time and go into the next session on a fixed schedule.” Where the OIG could not reconcile billed units with documented activity time, the units were flagged as improper or potentially improper. Wisconsin’s audit found that the majority of session notes documented continuous billing without any adjustment for meals or other non-therapy time.
Missing Documentation: Diagnostic Evaluations, Treatment Plans, Signatures, and Credentials
The largest categorical finding across the four reports is documentation that was not present in the record at all. Four gaps recurred: the diagnostic evaluation establishing eligibility for ABA, the treatment plan describing authorized services, parent or guardian signatures attesting to consent and receipt, and provider credentials tied to the rendering line on the claim. Each gap created exposure on a different dimension. Without a diagnostic evaluation, the service should not have been authorized in the first place. Without a treatment plan, the alignment between authorization and delivery cannot be verified. Without a signature, consent and receipt cannot be confirmed. Without credential documentation tied to the claim line, the rendering provider cannot be verified to have met the qualification level the code requires.
Colorado’s audit drew particular attention to the credentialing question. The state’s written rules did not, in the state’s view, require Registered Behavior Technician certification for behavior technicians delivering 97153, but state staff verbally told auditors that they did. The OIG flagged payments where the rendering technician held no RBT credential. Colorado disputed the finding on the grounds that the written rules did not establish the requirement. The point that translates beyond Colorado is that documentation tying the rendering provider’s credential level to the specific claim line is what auditors look for. Indiana has used its post-audit period to address exactly this dimension: as of August 2025, RBTs must enroll directly with IHCP and submit credential documentation to each managed care entity. The Indiana ABA reform bulletin extends that infrastructure with supervision standards and accreditation requirements that operationalize the OIG’s underlying credentialing concern.
Documentation Quality: Vague Narratives, Premature Signatures, and Identical Notes
Beyond presence-or-absence, the OIG flagged five quality patterns as potentially improper. First, vague activity descriptions that did not substantiate active treatment: notes that recorded “worked on goals” without specific behavioral targets, prompts, data, or intervention choices. Second, notes signed before the scheduled session ended, which by definition cannot authenticate what was billed. Third, identical or near-identical notes across sessions or across clients, which auditors treated as evidence that the note was not capturing what actually happened. Fourth, notes that referenced the wrong client, typically a copy-paste artifact. Fifth, recreational or academic activities documented without clear therapeutic intent: ABA can incorporate play and structured games, but where a note read as a recreation log rather than as a treatment record, the time was flagged.
Concurrent Billing With Speech and Occupational Therapy
Concurrent billing, sometimes called co-treatment, refers to ABA delivered during the same time window as another therapy. Some payers prohibit it. Some allow it under specific conditions. The OIG audits found that even when co-treatment was approved during the prior authorization period, most session notes did not describe what the ABA team did during the overlap or how that work supported the other service. Auditors treated the absence of co-treatment narrative as a documentation gap that converted the overlapping ABA time into a potentially improper payment. Concurrent billing restrictions are spreading across states, and the ABA Coding Coalition has been pushing back on the more restrictive readings. The defensive position for providers is to document explicitly: when ABA overlaps with another therapy, the ABA note must describe what the technician was doing, why it was clinically appropriate during the overlap, and how the work supported the other service. A note that says only “OT was present” is not enough.
Continuous High-Intensity Sessions and the Napping Finding
The most-quoted detail from the four OIG audits is the napping finding. Records in some sampled enrollee-months indicated children napping during sessions billed at high intensity, sometimes for seven-and-a-half or eight hours of continuous services without documented breaks. Auditors did not infer that those clients were not receiving any care. They inferred that the documented activity did not support the billed intensity, which converts the relevant time into a potentially improper payment. The evidence behind the dosage debate sits underneath this finding: high-intensity dosing has long been a clinical orthodoxy in ABA, and the OIG’s reading is that high-intensity dosing without documentation supporting medical necessity, duration, and active engagement is not reimbursable at the rate billed. The practical fix is to document interruptions. Meal breaks, transitions, naps, and parent pickups all happen in real-world service delivery. They should appear in the record, and the session notes covering any billed time must reflect aspects of the treatment plan delivered during that time. Naps, by definition, are not billable.
97156 Family Guidance and the Colorado Paradox
CPT code 97156 covers family adaptive behavior treatment guidance: parent training, caregiver coaching, and the work of teaching a family to support the treatment plan in the home. Colorado’s audit produced a striking finding. The state’s policy required family guidance services consistent with 97156. The state’s fee schedule did not allow 97156 to be billed. Providers were caught between a clinical requirement and a billing prohibition. CASP presenters expect Colorado to add 97156 to its fee schedule in response. The broader lesson is that providers must check, for every payer, whether the codes the policy requires are codes the fee schedule actually allows. Indiana’s BT202627 bulletin is moving in the same direction from a different starting point: it establishes a minimum standard of up to 18 hours of family guidance every six months under code 97156, with the specific application interpreted variably across managed care entities.
What “Good” Documentation Looks Like Under OIG Scrutiny
A defensible 97153 note identifies the rendering technician (with credential), the supervising QHP (with credential), the date of service, actual start and end times, the specific behavioral targets addressed, the interventions implemented, the data collected, the client’s responses, and any breaks or transitions during the session. The note is contemporaneous, signed at the close of the session, and tied to the treatment plan in effect on the date of service. A defensible 97155 note identifies the QHP delivering the protocol modification, the specific protocol reviewed, the analytic basis for the modification, the modification made, and the clinical reasoning. A defensible 97156 note identifies the QHP, the specific caregiver receiving the guidance, the content covered, the caregiver’s demonstrated understanding, and the connection to the child’s treatment goals. Family guidance is structured caregiver training, not informal parent conversation, and the note should look on paper like the structured intervention it is.
The Reports Are Free, the Lesson Is Expensive
CASP presenters described the four published OIG reports as a free training curriculum: a detailed catalog of what auditors expected, what they found, and what providers can do differently. Reading them as compliance training, rather than as headlines about other states, is the difference between being prepared when a state acts and being surprised. The cost of being surprised has been visible elsewhere. Massachusetts providers facing six-figure recoupments are encountering exactly the state-level enforcement that follows from federal-level audit findings. Maine’s $45.6 million audit is expected to produce provider-level recoupments through MaineCare’s Program Integrity Unit. Indiana is re-auditing the same dates of service the OIG examined and recovering dollars from providers. The accountability era arriving for autism care assumes the documentation discipline the OIG is asking for. The published reports are pointing at the gaps. Closing them is the work.
Frequently Asked Questions
What CPT codes did the OIG flag most often in the ABA audits?
The most common findings cluster around CPT codes 97153 (one-on-one direct adaptive behavior treatment), 97154 (group adaptive behavior treatment), 97155 (protocol modification by a qualified healthcare professional), and 97156 (family adaptive behavior treatment guidance). The two recurring patterns were 97153 billed when documented activities suggested 97154 (a group format), and 97155 billed when the documented activity was assessment or parent training rather than face-to-face protocol direction. CPT code 97151 (behavior identification assessment) also appeared in findings, particularly when assessment time was billed under other codes or when the assessment underlying ABA authorization was missing from the record.
What does the OIG actually want a 97153 session note to contain?
A defensible 97153 note identifies the rendering behavior technician (with credential), the supervising qualified healthcare professional (with credential), the date of service, the actual start and end times, the behavioral targets addressed during the session, the interventions implemented, the data collected, the client’s responses, and any breaks or transitions. The note must be contemporaneous (signed at the close of the session, not after the scheduled end), client-specific (not duplicative of notes for other clients), and substantively descriptive (not generic language such as “worked on goals”). Where a session note describes activities that fit a different code (group services, recreational time without therapeutic intent, parent training), the billed code must change to match what was actually delivered.
Does protocol modification under 97155 require an actual modification?
Some payers read the code that way; others do not. The original intent of the AMA CPT framework, as written by the ABA Coding Coalition, is that 97155 captures face-to-face direction by a qualified healthcare professional whose role includes the discretion to modify the protocol if needed, whether or not a modification was made on a given date. Some state Medicaid agencies and managed care entities apply that reading. Others apply a stricter reading, treating the absence of a documented modification as a failed compliance test. Providers must know which reading their specific payer uses and document accordingly. Where the stricter reading applies, the note must explicitly describe what was modified, why, and how the change is intended to alter the trajectory of treatment.
How do I document a session that includes meal breaks or non-treatment time?
Document the breaks and adjust the billed units accordingly. The OIG flagged session notes that recorded continuous all-day billing without any documented interruptions for meals, rest, or transitions. The expectation is not that ABA sessions never include breaks; it is that breaks are part of real service delivery and should appear in the record. A defensible note for a long session identifies billable treatment intervals discretely, with start and end times for each interval and a brief notation of what occurred during non-billed time. Records indicating a child napping during high-intensity billed services were called out specifically by auditors as evidence that documented activity did not support billed intensity.
What documentation does concurrent billing with speech or OT require?
Concurrent billing requires payer-level approval (typically through prior authorization) and session-level documentation describing what the ABA team did during the overlap and how the overlap was clinically appropriate. The OIG audits found that even when co-treatment was approved during the prior authorization period, most session notes failed to describe the ABA work during the overlapping window. A defensible co-treatment note identifies the other service (speech, OT, or other), the rendering provider for that service, the specific work the ABA technician or QHP did during the overlap, and the clinical rationale for delivering both services concurrently. Some payers prohibit concurrent billing entirely; others allow it under specific clinical conditions; documentation requirements vary, and providers must know each payer’s specific rule.
What is the Colorado paradox, and does it apply to other states?
The Colorado paradox is the OIG’s finding that Colorado’s policy required family guidance services consistent with CPT code 97156 but the state’s fee schedule did not allow 97156 to be billed. Providers were therefore caught between a clinical requirement and a billing prohibition. The pattern can appear in any state where the policy and the fee schedule are written by different teams or are updated on different cycles. Providers should check, for every payer, whether the codes the policy requires are codes the fee schedule actually allows. Where a gap exists, the right course is to flag it through the formal payer channel before the next audit cycle, not to fold the work into a different code or to deliver the work without billing for it.
If I find a documentation problem in my own records, what should I do?
Self-disclose and correct. Errors are a recognized category in payer compliance frameworks (distinct from fraud, waste, and abuse), and payers expect providers to identify and correct mistakes proactively. The CASP presenters described it directly: “We are humans. We all make mistakes. Payers know. They expect that. Our job is to make sure that we are honest brokers when we do make mistakes, and we raise our hand and say so.” The mechanics vary by payer, but generally include flagging the affected claims, refunding any overpayment associated with the error, documenting the corrective action taken (training, process change, system fix), and applying the corrective action going forward. Self-correction is treated very differently from a correction discovered through external audit. The window to act is the period before the audit notice arrives.
