Crystal's Coder Hub⚡ CPT 95913 — Nerve Conduction Studies; 13 or More Studies
Quick Reference
wRVU: 2.78 | Global Period: XXX | Assistant Payable: No | Bilateral Indicator: 3 The XXX global period means this code has no standard pre/post-operative period assigned — it is a diagnostic test, not a surgical procedure. Modifier -50 (bilateral) does NOT apply to this code; each nerve tested is individually counted toward the study total, and laterality is reflected in the ICD-10-CM diagnosis codes rather than on the CPT claim line. The bilateral indicator of 3 signals that the concept of bilateral surgery does not apply here. Assistant surgeon and co-surgeon modifiers (-80, -81, -82, -62) are not applicable to this diagnostic code.
📋 Clinical Description
CPT 95913 describes the performance of 13 or more nerve conduction studies (NCS) in a single encounter to assess peripheral nerve function. A single conduction study is defined by CMS and the AMA as a sensory conduction test, a motor conduction test with or without an F-wave test, or an H-reflex test — each type for each nerve counts as one distinct study, even if multiple anatomical sites on the same nerve are stimulated.1 This is the highest-tier code in the NCS series (95907-95913), which are tiered by total study count; you bill only one code per encounter — the single code matching the total study count — not individual codes per nerve tested.2
The NCS series measures the electrical properties of peripheral nerves: conduction velocity, amplitude, distal latency, and the presence or absence of F-waves and H-reflexes. These parameters distinguish axonal loss from demyelinating pathology, localize focal entrapments, and characterize generalized polyneuropathies. Documentation must include numerical data — specifically amplitude, latency, and velocity — for every nerve tested; narrative reports without raw data are a basis for denial under Medicare LCD L34594.1
This procedure may be performed in the following clinical contexts:
- Suspected polyneuropathy evaluation — A patient presents with bilateral distal numbness, tingling, and weakness; the ordering provider suspects diabetic peripheral neuropathy or Guillain-Barré syndrome. Testing 13+ nerves across multiple limbs is necessary to characterize the distribution, severity, and type (axonal vs. demyelinating) of the neuropathic process.
- Plexopathy workup — A patient with new-onset unilateral upper extremity weakness and sensory loss requires brachial plexus evaluation. Plexopathy per CMS Appendix J permits up to 12 NCS studies, and a complex case with bilateral involvement or concurrent polyneuropathy may clinically justify 13 or more.1
- Tarsal tunnel syndrome, bilateral — CMS Appendix J permits up to 11 studies for bilateral tarsal tunnel; complex bilateral lower extremity entrapment with concurrent systemic neuropathy may require expanded testing reaching the 13+ threshold.1
- Neuromuscular disease differentiation — Conditions such as ALS, multifocal motor neuropathy G61.82, or hereditary motor and sensory neuropathy G60.0 require extensive multi-nerve testing to distinguish motor neuron disease from peripheral neuropathy, justifying a large study count.
- Pre- and post-treatment monitoring — Patients undergoing chemotherapy with known neurotoxic agents (e.g., platinum-based or taxane regimens) may require comprehensive NCS panels to document neuropathy progression or improvement, with 13+ studies warranted to assess multiple nerve territories bilaterally.
🔬 Anatomical & Procedural Considerations
| Variant | Mechanism | Key Notes |
|---|---|---|
| Motor NCS | A surface electrode stimulates a peripheral nerve proximally; a recording electrode over the target muscle captures the compound muscle action potential (CMAP). Conduction velocity is calculated by dividing distance by the difference in latency between proximal and distal stimulation sites. F-waves, which reflect antidromic conduction to the anterior horn cell and back, can be captured during the same motor NCS and count as part of the same motor study. | Motor NCS is essential for evaluating motor neuropathies, radiculopathies, and ALS. The CMAP amplitude reflects the number of intact motor axons; reduced amplitude with preserved velocity suggests axonal loss. Prolonged distal latency with slow conduction velocity suggests demyelination, as seen in CIDP or Charcot-Marie-Tooth disease. |
| Sensory NCS | Surface electrodes stimulate a sensory nerve antidromically or orthodromically, generating a sensory nerve action potential (SNAP). Amplitude, latency, and conduction velocity are recorded. Each sensory nerve tested at each distinct site counts as one study. | SNAPs are often reduced or absent earlier than motor responses in length-dependent polyneuropathies. Absent sural nerve responses with preserved peroneal motor responses is a classic pattern for axonal sensory polyneuropathy. Sensory NCS findings help differentiate pre-ganglionic (root/spinal cord) lesions — where SNAPs are preserved — from post-ganglionic (peripheral nerve) lesions where SNAPs are abnormal. |
| H-Reflex / F-Wave | The H-reflex is the electrophysiologic correlate of the Achilles tendon reflex, assessing the S1 nerve root and proximal tibial nerve. F-waves are late motor responses reflecting conduction along the full length of a motor nerve, making them sensitive for proximal demyelinating lesions. Each H-reflex counts as a separate study; F-waves are counted within the corresponding motor NCS. | The H-reflex is particularly useful in early S1 radiculopathy when other findings are normal. F-wave prolongation is one of the earliest and most sensitive electrodiagnostic findings in Guillain-Barré syndrome G61.0. Because F-waves are included within their motor NCS study, they do not add to the total study count independently. |
Clinical Pearl
CMS Appendix J provides a table of reasonable maximum study counts per diagnostic category — for example, up to 12 studies for plexopathy and up to 10 for bilateral carpal tunnel.1 Reaching the 95913 threshold of 13+ studies is clinically appropriate for complex presentations involving bilateral multi-territory entrapments, generalized polyneuropathy with focal overlay, or concurrent systemic disease. However, you must be able to provide supplementary documentation justifying study counts that exceed the Appendix J maximums for that diagnostic category. Auditors specifically target high-volume NCS billing, and claims for 95913 will draw scrutiny if the diagnosis does not support the extended study count.
✅ Procedure Includes
- All nerve conduction study components performed during the encounter — every motor NCS, sensory NCS, F-wave study (when performed as part of a motor NCS), and H-reflex test is bundled into the single reported NCS tier code; you may not unbundle individual nerves and report separate lower-tier codes alongside 95913.
- Electrode placement and skin preparation — application of surface stimulating and recording electrodes, measurement and marking of nerve segments, and any conductive gel or skin preparation required for signal acquisition.
- Signal acquisition and waveform recording — real-time acquisition and documentation of CMAP, SNAP, F-wave, and H-reflex waveforms using EMG equipment, including calibration and impedance checks.
- Interpretation and written report — the performing provider’s analysis of all waveform data, including amplitude, latency, conduction velocity, and F-wave/H-reflex latency for each nerve studied; a written or electronic report with these numerical values is required by CMS for reimbursement.1
- Immediate pre-procedure clinical assessment — brief neurological assessment immediately preceding or during the study to guide nerve selection is included; however, a separate and identifiable E/M service beyond the inherent pre-procedure assessment may be reported separately with modifier -25.
- Comparison to established normative values — interpretation includes comparison to age- and height-adjusted normative data and to the contralateral limb where applicable; contralateral limb testing to establish individual normative values is covered when medical necessity is documented.
❌ Excludes / Do Not Report Together
| Code | Description | Relationship |
|---|---|---|
| 95912 | Nerve conduction studies; 11-12 studies | 95912 and 95913 are mutually exclusive; report only the single code that corresponds to the total number of studies performed during the encounter. Reporting both on the same date for the same patient constitutes unbundling and will result in denial of the lower-tier code. |
| 95905 | Motor and/or sensory nerve conduction using preconfigured electrode array(s), each limb | 95905 uses a different methodology (preconfigured electrode arrays such as NC-stat) and cannot be reported on the same date as 95907-95913. These are separate code families representing different testing technologies; mixing them on the same claim is not appropriate. |
| 95860 | Needle electromyography (EMG); one extremity | When NCS (95907-95913) is performed on the same day as needle EMG, the add-on EMG codes 95885-95887 must be used instead of the standalone EMG codes 95860-95864. Reporting 95860-95864 with 95907-95913 on the same date is incorrect and will be bundled or denied by most payers. |
| 95886 | Needle EMG, complete study; 4 or more extremities including thoracic paraspinal muscles | 95886 is the correct add-on EMG code to pair with NCS when four or more extremities plus thoracic paraspinals are examined on the same day. It is separately reportable alongside 95913 when medically necessary and documented, and no modifier is needed to bill both on the same date.2 |
Bundling Alert
CPT 95913 has a global period of XXX, meaning there is no formal post-operative period during which related services would be bundled — however, the procedure itself bundles all individual nerve studies performed during that encounter. Medicare and most commercial payers will not pay for 95913 plus any other NCS tier code (95907-95912) on the same date for the same patient. Standalone EMG codes 95860-95864 are also bundled into the NCS codes when performed on the same day; use only 95885-95887 for the EMG component. Audit risk is elevated for any claim reporting 95913 where the documented diagnosis from CMS Appendix J would typically require fewer than 13 studies — always ensure the operative/procedure report clearly justifies the expanded study count with a narrative explanation if Appendix J maximums are exceeded.1
🌳 Code Tree — Medicine: Neurology and Neuromuscular Procedures
CPT 95900-95999 Medicine: Neurology and Neuromuscular Procedures
│
├── 95900-95904 Nerve Conduction (Legacy/Unlisted)
│ └── 95905 Motor and/or sensory nerve conduction, preconfigured electrode array, each limb (Global: XXX)
│
├── 95907-95913 Nerve Conduction Studies (Tiered by Study Count)
│ ├── 95907 Nerve conduction studies; 1-2 studies (Global: XXX)
│ ├── 95908 Nerve conduction studies; 3-4 studies (Global: XXX)
│ ├── 95909 Nerve conduction studies; 5-6 studies (Global: XXX)
│ ├── 95910 Nerve conduction studies; 7-8 studies (Global: XXX)
│ ├── 95911 Nerve conduction studies; 9-10 studies (Global: XXX)
│ ├── 95912 Nerve conduction studies; 11-12 studies (Global: XXX)
│ └── ▶▶ 95913 ◀◀ Nerve conduction studies; 13 or more studies ← YOU ARE HERE (Global: XXX)
│
├── 95860-95870 Needle Electromyography (Standalone — use when no NCS same day)
│ ├── 95860 EMG; 1 extremity with or without related paraspinal muscles (Global: XXX)
│ ├── 95861 EMG; 2 extremities (Global: XXX)
│ ├── 95863 EMG; 3 extremities (Global: XXX)
│ └── 95864 EMG; 4 extremities (Global: XXX)
│
└── 95885-95887 Needle EMG Add-On Codes (use when NCS performed same day)
├── 95885 EMG, each extremity, with NCS same day; limited (fewer than 5 muscles) (Global: ZZZ)
├── 95886 EMG, each extremity, with NCS same day; complete (5+ muscles, 3+ nerves/4+ spinal levels) (Global: ZZZ)
└── 95887 EMG, non-extremity muscles, with NCS same day (Global: ZZZ)
💰 RVU & Reimbursement Profile
| Component | Value |
|---|---|
| Work RVU | 2.78 |
| Global Period | XXX (no global period — diagnostic test) |
| Bilateral Indicator | 3 (bilateral concept does not apply) |
| Assistant Surgeon | Not payable |
| Co‑Surgeon | Not payable |
| Team Surgery | Not payable |
| PC/TC Split | Yes — modifier -26 (professional) and -TC (technical) are applicable |
| Modifier -51 Exempt | No |
| Anesthesia | Not applicable — no anesthesia required |
Bilateral Billing Rules
CPT 95913 carries a bilateral indicator of 3, which means the bilateral concept does not apply in the typical surgical sense — you do not append modifier -50 or use -RT/-LT on the NCS code itself. Laterality is instead captured in the ICD-10-CM diagnosis codes (e.g., G56.03 for bilateral carpal tunnel). The PC/TC split is particularly relevant for 95913 because in many practice settings the neurologist or physiatrist who interprets the study (professional component, modifier -26) may be separate from the testing facility or technician who performs the tracing (technical component, -TC). When one provider performs and interprets the entire study in their own office, the global code (no modifier) is billed. If the study is performed in a hospital outpatient department or independent diagnostic testing facility, the professional and technical components must be billed separately.2
🏷️ Modifier Reference
| Modifier | Name | When to Apply |
|---|---|---|
| -26 | Professional Component | Append when the physician provides only the interpretation and written report, while the technical performance (electrode placement, signal acquisition) is performed by a separate entity such as a hospital, IDTF, or PT with ABPTS certification. The report must include numerical data for all nerves studied and a clinical interpretation signed by the billing provider. |
| -TC | Technical Component | Append when the facility or testing provider performs only the electrode placement and signal acquisition without providing the interpretation. Facilities such as hospitals billing under the OPPS and IDTFs billing separately from the interpreting physician use this modifier. Cannot be billed by the same provider who bills -26 on the same claim. |
| -25 | Significant, Separately Identifiable E/M | Append to the E/M code (not to 95913) when a separate and identifiable evaluation and management service is provided on the same day as the nerve conduction study. The E/M must be beyond the routine pre-procedure clinical assessment inherent to the NCS; medical necessity for the separate E/M must be clearly documented in the medical record per CMS LCD L34594.1 |
| -59 | Distinct Procedural Service | Use when 95913 is billed alongside an add-on EMG code (95885-95887) and payer edits are triggering a bundling denial in error. However, note that NCS and EMG add-on codes (95885-95887) are recognized as complementary and do not routinely require modifier -59 together — check payer-specific edit policy before appending. Do not use -59 to unbundle NCS tier codes (95907-95912) from 95913. |
| -GQ | Via Asynchronous Telecommunications | Applicable when the professional interpretation component is provided via a store-and-forward telehealth modality, where the tracing is transmitted asynchronously for remote interpretation. Verify payer coverage policy, as telehealth coverage for electrodiagnostic interpretation varies by payer and state. |
| -GT | Via Interactive Audio and Video | Used for real-time interactive telehealth delivery of the professional component when permitted by payer policy. Most commonly relevant for remote neurology interpretation services. Medicare has specific restrictions on which services may be billed via telehealth under POS 02. |
Note: Modifiers -RT, -LT, -50, -E1-E4, -24, -52, -53, -58, -78, -79, -80, -81, -82, -62 are not applicable to CPT 95913, which is a diagnostic medicine code without a surgical global period or bilateral surgical designation.
🩺 Common ICD‑10‑CM Pairings
Primary Diagnosis Group — Peripheral Entrapment / Focal Neuropathy
| ICD‑10 | Description | HCC? | Notes |
|---|---|---|---|
| G56.01 | Carpal tunnel syndrome, right upper limb | No | Most common indication for NCS in outpatient neurology; median nerve motor and sensory studies plus ulnar comparative studies often push total study count toward or past 13 in bilateral cases. Always code to the specific laterality. |
| G56.02 | Carpal tunnel syndrome, left upper limb | No | Report alongside G56.01 when bilateral testing is performed. Bilateral carpal tunnel per Appendix J permits up to 10 studies, so documentation must justify exceeding 10 if 95913 is billed for this indication alone. |
| G56.03 | Carpal tunnel syndrome, bilateral upper limbs | No | Use when bilateral CTS is confirmed or strongly suspected and bilateral studies are performed simultaneously. Replaces the use of both G56.01 and G56.02 when the bilateral code is the most specific representation. |
| G57.51 | Tarsal tunnel syndrome, right lower limb | No | Posterior tibial nerve entrapment at the flexor retinaculum of the ankle; bilateral tarsal tunnel per Appendix J permits up to 11 studies. Concurrent upper and lower extremity studies or additional H-reflex/F-wave studies can bring the total to 13+. |
| G57.52 | Tarsal tunnel syndrome, left lower limb | No | Code bilaterally when applicable; document medical necessity for bilateral testing if symptoms are primarily unilateral. |
Secondary Group — Generalized Neuropathy / Polyneuropathy
| ICD‑10 | Description | HCC? | Notes |
|---|---|---|---|
| G61.0 | Guillain-Barré syndrome | No | Classic indication for extensive NCS; bilateral multi-nerve testing across upper and lower extremities with F-wave studies routinely exceeds 13. Expect markedly prolonged distal latencies, slowed conduction velocity, and absent or markedly prolonged F-waves in demyelinating GBS. |
| G61.81 | Chronic inflammatory demyelinating polyneuritis (CIDP) | No | CIDP workup routinely requires 13+ studies to document the multifocal demyelinating pattern across multiple nerves and limbs. Serial NCS is used to monitor treatment response; document medical necessity for repeat testing with clinical justification. |
| E11.42 | Type 2 diabetes mellitus with diabetic polyneuropathy | Yes (HCC) | One of the most common polyneuropathy diagnoses paired with NCS; length-dependent sensorimotor polyneuropathy typically requires bilateral lower extremity and upper extremity nerve testing. This is an HCC code — accurate capture of diabetic polyneuropathy supports risk adjustment. |
| G62.0 | Drug-induced polyneuropathy | No | Neurotoxic chemotherapy agents (platinum compounds, taxanes, vinca alkaloids) are common causes; NCS quantifies the severity and distribution of chemotherapy-induced peripheral neuropathy (CIPN). |
Etiology / Complication
| ICD‑10 | Description | HCC? | Notes |
|---|---|---|---|
| G54.0 | Brachial plexus disorders | No | Plexopathy per Appendix J permits up to 12 NCS studies; with bilateral involvement or concurrent systemic neuropathy, 13+ studies may be clinically necessary. Supplementary documentation justifying the expanded count is required. |
| G60.0 | Hereditary motor and sensory neuropathy (Charcot-Marie-Tooth) | No | CMT is characterized by diffuse slowing of nerve conduction velocities; extensive bilateral multi-nerve testing is standard. Uniformly slow conduction (e.g., median motor CV <38 m/s) is a diagnostic hallmark and justifies comprehensive NCS. |
Coding Specificity Reminder
Never use unspecified or vague diagnosis codes — such as G62.9 (Polyneuropathy, unspecified) or M54.9 (Dorsalgia, unspecified) — as the primary justification for a comprehensive 13+ study NCS panel. CMS LCD L34594 and most commercial payer policies require a specific diagnosis demonstrating medical necessity for the number of studies performed.1 Laterality must be coded to the highest specificity available (right, left, bilateral) for all mononeuropathy and entrapment codes. For diabetic neuropathy diagnoses, always link the type of diabetes to its neurological complication using the combination codes in the E08-E13 range rather than coding them separately. Accurate, specific diagnosis coding on NCS claims is one of the most direct ways to defend against post-payment audit recoupment.
🏥 MS‑DRG Considerations
CPT 95913 is a Medicine section diagnostic procedure code and does not directly map to or drive an MS-DRG assignment in the inpatient setting. When a consulting neurologist or physiatrist performs NCS on a hospitalized patient (e.g., to evaluate new-onset Guillain-Barré syndrome, critical illness polyneuropathy, or suspected ALS), the service is billed on a professional/Part B claim using 95913 and does not affect the facility’s MS-DRG, which is driven by ICD-10-PCS procedure codes and ICD-10-CM diagnoses. In the outpatient setting, 95913 may be subject to OPPS packaging rules when performed in a hospital outpatient department — check current APC assignment. The underlying diagnoses documented to justify 95913, such as G61.0 (Guillain-Barré syndrome) or G61.81 (CIDP), do carry significant inpatient DRG implications (e.g., MDC 01 Nervous System), so thorough and specific diagnosis coding on the professional claim supports the complete clinical picture for any concurrent or subsequent inpatient encounter.
🔧 ICD‑10‑PCS Equivalents
| PCS Code | Full Description | Modality |
|---|---|---|
| 4A01XMZ | Measurement of Peripheral Nervous, Electrical Activity, External Approach, No Qualifier | Electrical Activity Measurement |
| 4A01X4Z | Measurement of Peripheral Nervous, Electrical Activity, Percutaneous Approach, No Qualifier | Electrical Activity Measurement (surface needle-adjacent) |
| 4A00XMZ | Measurement of Central Nervous, Electrical Activity, External Approach, No Qualifier | Electrical Activity Measurement (CNS monitoring context) |
| 4A01XKZ | Measurement of Peripheral Nervous, Conductivity, External Approach, No Qualifier | Conductivity Measurement |
PCS Character Analysis (Representative code: 4A01XMZ)
| Position | Character | Value | Definition |
|---|---|---|---|
| 1 | Section | 4 | Measurement and Monitoring — the section for physiological measurement procedures including electrodiagnostic testing. |
| 2 | Body System | A | Physiological Systems — encompasses the peripheral and central nervous systems as measured physiological entities rather than anatomically operated-upon structures. |
| 3 | Root Operation | 0 | Measurement — defined as “determining the level of a physiological or physical function at a point in time,” which precisely describes nerve conduction velocity, amplitude, and latency assessment. |
| 4 | Body Part | 1 | Peripheral Nervous — designates the peripheral nervous system, including motor, sensory, and autonomic peripheral nerves of the upper and lower extremities and cranial nerves. |
| 5 | Approach | X | External — surface electrode placement on intact skin overlying peripheral nerves; no skin incision or percutaneous penetration is required for standard NCS. |
| 6 | Device | M | Electrical Activity — specifies that the measured physiological parameter is electrical activity (action potentials, waveforms). |
| 7 | Qualifier | Z | No Qualifier — no further qualification of the procedure is specified. |
Root Operation Comparison
- Measurement (0) vs. Monitoring (1): Measurement captures a physiological value at a single point in time and is the correct root operation for a standard NCS session. Monitoring would be used only for continuous intraoperative nerve monitoring over a prolonged period (e.g., intraoperative neurophysiology during spine surgery), not for a diagnostic outpatient NCS.
- Peripheral Nervous (1) vs. Central Nervous (0): Standard NCS codes to Peripheral Nervous (character 4 = 1). Central Nervous (4 = 0) would apply to procedures monitoring CNS electrical activity such as EEG. A combined NCS/EEG session would require separate PCS codes for each body system.
- Conductivity (K) vs. Electrical Activity (M): Conductivity (K) most precisely maps to nerve conduction velocity measurement. Electrical Activity (M) is the more commonly used character in coding practice and captures the broader waveform analysis component of NCS. Either may be acceptable depending on institutional coding guidelines and the specific physiological parameter being documented.
📝 Coding Examples
Example 1
Clinical Scenario: A 58-year-old woman with Type 2 diabetes mellitus and a 6-month history of bilateral hand numbness and bilateral foot tingling is referred to a neurologist for electrodiagnostic evaluation. The neurologist performs bilateral median motor and sensory NCS, bilateral ulnar motor and sensory NCS, bilateral radial sensory NCS, bilateral tibial motor NCS with F-waves, bilateral peroneal motor NCS with F-waves, bilateral sural sensory NCS, and bilateral H-reflexes — totaling 18 individual studies. A separate and identifiable E/M service is performed to obtain an interval history and perform a focused neurological examination prior to the test, which is documented separately in the medical record.
| Field | Code | Rationale |
|---|---|---|
| CPT 1 | 99213-25 | Separate, identifiable E/M performed on the same day as NCS; modifier -25 appended to the E/M (not the NCS) to indicate the service is above and beyond the pre-procedure assessment inherent to 95913. Documentation must support the medical decision making level. |
| CPT 2 | 95913 | 18 total NCS studies performed; 13+ study threshold met, making 95913 the correct and only NCS tier code to report. |
| PDx | E11.42 | Type 2 diabetes mellitus with diabetic polyneuropathy — specific combination code that captures both the etiology and the neurological complication; this is an HCC-relevant code. |
Note
Do not report both the E/M and 95913 without modifier -25 on the E/M. The routine pre-procedure assessment is already included in 95913; only a separately identifiable E/M service beyond that inherent assessment supports separate billing. Ensure the documentation clearly distinguishes the E/M from the NCS pre-procedure evaluation.
Example 2
Clinical Scenario: A 42-year-old male is admitted to the hospital with ascending weakness and areflexia over 5 days. The attending neurologist suspects Guillain-Barré syndrome and orders an inpatient electrodiagnostic study. A physiatrist consultant performs 14 nerve conduction studies across bilateral upper and lower extremities, including bilateral median, ulnar, tibial, and peroneal motor NCS with F-waves, bilateral sural sensory NCS, and bilateral H-reflexes. Needle EMG of four extremities including thoracic paraspinals is performed on the same day using the add-on EMG codes.
| Field | Code | Rationale |
|---|---|---|
| CPT 1 | 95913 | 14 NCS studies meet the 13+ threshold; billed on the professional claim regardless of inpatient setting. |
| CPT 2 | 95886 | Complete needle EMG of 4+ extremities performed same day as NCS; add-on EMG code 95886 is the correct pairing. Standalone EMG codes 95860-95864 must NOT be used when NCS is performed the same day. |
| PDx | G61.0 | Guillain-Barré syndrome — specific, high-acuity diagnosis that directly supports the clinical necessity for 14+ NCS studies. |
Warning
Example 3
Clinical Scenario: A neurologist at a freestanding IDTF performs the technical component of a 15-study NCS on a patient with suspected CIDP. The physiatrist who supervises the testing and provides the written interpretation with full numerical data works at a separate practice and bills only for the professional interpretation.
| Field | Code | Rationale |
|---|---|---|
| IDTF CPT | 95913-TC | Technical component only — the IDTF performed the electrode placement, stimulation, and waveform acquisition; they bill for the technical work using modifier -TC. |
| Physiatrist CPT | 95913-26 | Professional component only — the interpreting physician provides the report with clinical analysis of all numerical data and the final impression; billed with modifier -26. |
| PDx | G61.81 | Chronic inflammatory demyelinating polyneuritis — appropriate high-specificity diagnosis for CIDP evaluation with 13+ studies. |
Global period reminder
CPT 95913 carries a global period of XXX, meaning there is no pre- or post-operative period — this code can be billed each time a qualifying NCS session is performed. There is no restriction on repeat NCS testing based solely on a global period; however, medical necessity for repeat testing must be clinically justified and documented, and frequency of testing is subject to clinical reasonableness under LCD L34594.1
⚠️ Common Coding Pitfalls
-
Pitfall 1: Reporting multiple NCS tier codes on the same date. Some coders mistakenly bill, for example, 95911 and 95913 together to represent studies performed in two separate sessions or on two separate limbs within the same day. This is incorrect — the AMA and CMS require that all studies performed in a single encounter be totaled and reported under a single tier code. Reporting two tier codes on the same DOS for the same patient will result in bundling edits.
-
Pitfall 2: Using standalone EMG codes (95860-95864) with NCS on the same day. When needle EMG and NCS are performed on the same calendar date, the add-on EMG codes (95885, 95886, 95887) must replace the standalone EMG codes. Using 95860-95864 alongside any 95907-95913 code will trigger NCCI bundling edits and result in denial of the EMG code.1
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Pitfall 3: Missing or incomplete numerical data in the report. CMS Billing and Coding Article A57478 explicitly states that claims will be denied when the report does not include amplitude, latency, and velocity data for each nerve studied.1 A narrative summary without raw numerical data is a common audit finding that leads to post-payment recoupment. Ensure every report includes a data table with all recorded values.
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Pitfall 4: Billing 95913 when the diagnosis does not support 13+ studies. CMS Appendix J provides maximum study counts per diagnosis category — for example, unilateral carpal tunnel typically requires only 7 studies. If 95913 is reported for a diagnosis that Appendix J associates with far fewer than 13 studies, the claim will be flagged for medical necessity review. The documentation must include explicit clinical reasoning explaining why the expanded study count was necessary for that specific patient.
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Pitfall 5: Appending modifier -50 or -RT/-LT to 95913. The bilateral indicator of 3 means bilateral and laterality modifiers are not applicable to this CPT code. Laterality is captured in the ICD-10-CM diagnosis codes. Appending -50 to 95913 will cause the claim to be rejected or priced incorrectly by payers who follow Medicare billing rules.
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Pitfall 6: Failing to account for PC/TC split billing rules at facility-based settings. When NCS is performed in a hospital outpatient department or IDTF, the professional and technical components must be billed separately with modifiers -26 and -TC respectively. A physician who performs and interprets an NCS in their own office bills the global code (no modifier). Billing the global code when the test is performed at a facility — or failing to bill -TC when the interpreting physician is separate from the performing facility — results in overpayment or underpayment that can trigger compliance issues.2