The review of billing eligibility and reimbursement policies was conducted between July and October 2018. The main data source was state Medicaid FFS plans. The following search and data extraction methods were used in the review.

Search Domain and Strategy

The search domain was documentation of billing eligibility and reimbursement available online within the public domain. First, we identified each state's official Medicaid website. From there we looked for information for providers, following links with designations such as "For Providers" or "Provider Resources." Once there, we searched for three types of documentation:

  1. Provider and/or billing manuals. An SUD-specific provider/billing manual would be the first resource to review if available. If an SUD-specific manual was not available, we reviewed manuals related to behavioral health. In the absence of behavioral health-related manuals, we searched general provider/billing manuals.

  2. Fee schedules. If sufficient detail was not available from provider manuals, we searched SUD-specific or behavioral health-related fee schedules. In the absence of SUD-related or behavioral health-related fee schedules, we reviewed general fee schedules for the reimbursement codes selected for this study.

  3. Provider enrollment resources. We searched these resources for relevant information on SUD practitioner eligibility to enroll in Medicaid as an independent provider type. If information was unavailable, we called the plan's "provider relations" line and used the information, if supplied. In some states, billing eligibility was inferred from information in the billing manuals.

Approach to Identifying Alternate Billing Codes

It was expected that different coding systems would be used across state plans. Although the review was guided by a set of eight HCPCS codes, we attempted to identify a comparable alternate code when one of those codes was not in use in a given state. For some codes, the closest alternative we selected is not an exact match, which is a limitation of this study. Below is our approach to identifying alternate codes.

Original Code Approach to Identifying Alternate Code
H0001 = Alcohol and/or drug assessment In the absence of H0001 we looked for a code associated with assessment. If there was a choice between an assessment code that does not involve diagnostic evaluation and one that does, we chose the code without diagnostic evaluation to best align with H0001. However, if a diagnostic evaluation code was the only available replacement, we used it as an alternative (e.g., CPT code 90791).
H0049 = Alcohol and/or drug screening We looked for codes associated with "screening" specifically. We did not use diagnostic evaluation codes in place of screening.
H0050 = Alcohol and/or drug services, brief intervention, per 15 minutes We searched for any code associated with brief intervention (detail unspecified) or SBIRT specifically.
H0004 = Behavioral health counseling and therapy, per 15 minutes We looked for individual counseling or psychotherapy codes. If the code description mentioned SUD specifically, we used it, if not, we used a general individual psychotherapy code, the most common of which was CPT code 90832--individual psychotherapy, per 30 minutes. We did not identify an equivalent CPT code for a 15-minute increment.
H0038 = Self-help/peer services, per 15 minutes If H0038 was not used, we looked for any code related to peer services.
H0006 = Alcohol and/or drug services; case management We looked for an alternate code containing a reference to case management in its description.
H0007 = Alcohol and/or drug services; crisis intervention We looked for an alternate code containing a reference to crisis intervention in its description.
H0015 = Alcohol and/or drug services; intensive outpatient In the absence of a code specifically designated for intensive outpatient services, we used a code for "day treatment," if available.

Data were extracted into an Excel template for standardization and analysis.

Commercial Insurance

For commercial insurance, we used UnitedHealth/Optum's Provider Express portal[9] which lists the practitioner types eligible to enroll in Optum's network as "individually-contracted clinicians" in all 50 states and D.C. The data were compiled in July 2018. We searched for similar data on billing eligibility from other national commercial health insurers but did not find any information in the public domain.