Use of Modifier 59 and X{EPSU} (XE, XP, XS, XU)
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Defines CareSource's billing, coding, and documentation expectations for reporting Modifier 59 and the more specific X{EPSU} modifiers (XE, XP, XS, XU) and explains when claims may be reviewed, denied, or recovered. Applies to providers submitting claims to CareSource.
No material clinical or coverage changes in this revision.
When Modifiers Indicate Distinct Procedural Services
Modifier applicability criteria
When modifiers indicate distinct procedural services they will be considered for reimbursement only when documentation supports distinctness per CMS/NCCI guidance and CareSource rules. Reimbursement is dependent on submission of appropriate CPT/HCPCS codes with modifiers and medical record documentation.
XS conditions
- Applies to surgical, non-surgical therapeutic, or diagnostic procedures that are performed at different anatomic sites.
- Procedures are not ordinarily performed or encountered on the same day.
- Cannot be described by one of the more specific anatomic NCCI Procedure-to-Procedure (PTP)–associated modifiers (eg, RT, LT, E1–E4, FA, F1–F9, TA, T1–T9, LC, LD, RC, LM, RI).
XE conditions
- Applies to surgical, non-surgical therapeutic, or diagnostic procedures performed during different patient encounters.
- Cannot be described by one of the more specific NCCI PTP-associated modifiers (eg, 24, 25, 27, 57, 58, 78, 79, 91).
- May also be used when two timed procedures are performed during the same encounter but occur sequentially (the first service must be completed before the next service begins).
XU conditions
- Applies to surgical, non-surgical therapeutic, or diagnostic procedures performed at separate anatomic sites or separate patient encounters on the same date of service.
- May be used when a diagnostic procedure is performed before a therapeutic procedure only when all of the following apply: the diagnostic procedure is the basis for the therapeutic procedure; it occurs before and is not mingled with services required by the therapeutic intervention; it provides the information needed to decide whether to proceed; and it is not an inherent component of the therapeutic intervention.
- May be used when a diagnostic procedure is performed after a therapeutic procedure only when all of the following apply: the diagnostic procedure is not a common, expected, or necessary follow-up; it occurs after completion and is not mingled with services the therapeutic intervention requires; and it does not constitute a service that would have otherwise been required during the therapeutic intervention.
Modifiers and Code Guidance
| 59 | Modifier 59 - Distinct procedural service |
| XE | Separate Encounter - distinct because it occurred during a separate encounter |
| XP | Separate Practitioner - distinct because performed by a different practitioner |
| XS | Separate Structure - distinct because performed on a separate organ/structure |
| XU | Unusual Non-Overlapping Service - distinct because it does not overlap usual components of the main service |
Claims Review, Documentation, and Appeals
Claims may be selected for pre- or post-payment review and recovery
Claims billed with modifier 59 or X{EPSU} may be flagged for either a prepayment or post-payment coding review. For prepayment review, once the claim line has been validated it will be processed for payment or denied for incorrect use of the modifier; for post-payment review, if the claim line is not supported by the documentation CareSource will recover the payment when applicable.
Provide complete documentation and follow appeal procedures
Submitting providers are responsible for providing accurate and complete documentation to substantiate modifier use; failure to do so may result in denial. Standard appeal rights apply for both pre- and post-payment review outcomes.
- Use X{EPSU} modifiers before modifier 59 when appropriate.
- The use of modifiers must be fully supported in the medical record and/or office notes.
Key Terms and Code Systems
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