Department of Health and Human Services 

OFFICE OF 

INSPECTOR GENERAL 

QUESTIONABLE BILLING FOR 

MEDICARE 

ELECTRODIAGNOSTIC TESTS 

Daniel R. Levinson 

Inspector General 

April 2014 

OEI-04-12-00420 
 

 

EXECUTIVE SUMMARY: Questionable Billing for Medicare 

Electrodiagnostic Tests 

OEI-04-12-00420 

WHY WE DID THIS STUDY 

In 2011, Medicare paid approximately $486 million to 21,700 physicians who billed for 

electrodiagnostic tests for 877,000 beneficiaries. Electrodiagnostic tests are used to 

evaluate patients who may have nerve damage. Recent investigations have found that 

electrodiagnostic testing is an area vulnerable to fraud, waste, and abuse. For example, in 

2011, following work by the Medicare Fraud Strike Force, a group of physicians was 

charged with fraudulently billing Medicare $113 million for false claims, including 

claims for electrodiagnostic tests. The Centers for Medicare & Medicaid Services (CMS) 

issues comparative billing reports to providers for a variety of services, including 

electrodiagnostic testing. Such reports are intended to proactively educate providers and 

to help them identify and correct errors in their billing. 

HOW WE DID THIS STUDY 

We developed seven measures of questionable billing on the basis of past Office of 

Inspector General work and input from CMS staff. We analyzed Medicare 2011 

electrodiagnostic test claims to identify physicians who had unusually high billing for at 

least one of these measures. We also determined whether physicians with questionable 

billing for electrodiagnostic tests received comparative billing reports in 2011 for such 

tests. Finally, we identified the geographical areas with the highest amounts of 

questionable billing. 

WHAT WE FOUND 

In 2011, 4,901 physicians had questionable billing for Medicare electrodiagnostic tests 

totaling $139 million. Additionally, we found that approximately 20 percent of these 

physicians received comparative billing reports in 2011 on the basis of their 2010 billing 

for electrodiagnostic tests. Finally, physicians in the New York, Los Angeles, and 

Houston areas had the highest total questionable billing for Medicare electrodiagnostic 

tests in 2011. 

WHAT WE RECOMMEND 

We recommend that CMS (1) increase its monitoring of billing for electrodiagnostic 

tests, (2) provide additional guidance and education to physicians regarding 

electrodiagnostic tests, and (3) take appropriate action regarding physicians whom we 

identified as having inappropriate or questionable billing. CMS partially concurred with 

our first two recommendations and concurred with the third one. 
 

TABLE OF CONTENTS 

Objectives ....................................................................................................1 

Background..................................................................................................1 

Methodology................................................................................................6 

Findings......................................................................................................11
 

In 2011, 4,901 physicians had questionable billing for Medicare 

electrodiagnostic tests totaling $139 million .................................11
 

Thirty-eight percent of physicians with questionable billing for 

electrodiagnostic tests were in 10 metropolitan areas ....................17 

Conclusion and Recommendations ............................................................19 

Agency Comments and Office of Inspector General Response .....21 

Appendixes ................................................................................................22 

A: Number and Percentage of Medicare Physicians With 

Questionable Billing for Electrodiagnostic Tests in Each 

Specialty, 2011 ...............................................................................22 

B: Number and Percentage of Medicare Physicians Who 

Exceeded Thresholds of Questionable Billing for 

Electrodiagnostic Tests by Specialty Group, 2011 ........................24 

C: Physicians With Unusually High Billing by Each Measure of
 

Questionable Billing, 2011 ............................................................25 

D: Metropolitan Areas With the Highest Number of Physicians 

With Questionable Billing by Specialty Group, 2011 ...................27 

E: Geographical Areas of Physicians With Three Measures of 

Questionable Billing, 2011 ............................................................28 

F: Geographical Areas of Top 10 Physicians With Questionable 

Billing, 2011...................................................................................30 

G: Agency Comments ...................................................................31 

 Acknowledgments.......................................................................................35
 
 

 

 

 

OBJECTIVES 

To determine the extent to which: 

1.	 physicians exhibited questionable billing for electrodiagnostic tests in 

2011, and 

2.	 questionable billing by physicians varied by geographical location. 

BACKGROUND 

Recent investigations have found that electrodiagnostic testing is an area 

vulnerable to fraud, waste, and abuse. For example, in 2011, the Medicare 

Fraud Strike Force charged a group of physicians in two cities with 

fraudulently billing Medicare $113 million for false claims, including 

claims for electrodiagnostic tests.1 Further, the growth of Medicare 

spending on electrodiagnostic testing has outpaced the growth in overall 

Medicare spending in recent years. From 2002 to 2011, spending for 

electrodiagnostic testing under Medicare Part B increased 74 percent, from 

$279 million to $486 million.2 In comparison, during the same timeframe, 

overall Medicare spending for Part B items and services increased 

50 percent.3 

Overview of Electrodiagnostic Tests 

Electrodiagnostic tests are used to evaluate patients who may have nerve 

damage. These specialized tests measure the electrical activity of the 

muscles and nerves and detect abnormalities of the peripheral nervous 

system (i.e., nerves outside the brain and spinal cord). 

Several conditions, including diabetes and carpal tunnel syndrome, can 

cause peripheral nerve damage. Two common electrodiagnostic tests to 

1

 The Detroit, MI, cases involve $23 million in false Medicare claims for home health 

care, nerve conduction tests, psychotherapy, physical therapy and podiatry. The 

Brooklyn, NY, cases involve $90 million in false Medicare billings for physical therapy, 

proctology services and nerve conduction tests. Department of Justice, Medicare Fraud 

Strike Force Charges 111 Individuals for More Than $225 Million in False Billing and 

Expands Operations to Two Additional Cities. Accessed at 

http://www.justice.gov/opa/pr/2011/February/11-ag-202.html on June 8, 2012. 2

 In 2011, Medicare spending on electrodiagnostic tests represented approximately 

0.4 percent ($486 million of $126 billion) of all Medicare Part B spending. Health and 

Human Services (HHS) Office of Inspector General (OIG) analysis of 2002 and 2011 

Part B Analytics Reports (PBAR) National Procedure Summary File. 

3

 Ibid. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 1 
 

 

 

 

 

 

 

 

assess nerve damage are nerve conduction tests (NCT) and needle 

electromyography tests (EMG).4 

NCTs. NCTs are noninvasive procedures used to evaluate muscle or nerve 

damage. Standard NCTs include a stimulus that delivers a small electrical 

current to the patient’s skin near the nerves being tested, causing the 

nerves to respond. The electrical signals produced by nerves and muscles 

are typically recorded and interpreted by a physician specifically trained in 

electrodiagnostic medicine. Results from NCTs provide information about 

the speed, size, and shape of the nerve in response to an electrical 

stimulus. Physicians typically test many different motor and sensory 

nerves to determine the presence of nerve damage. 

Needle EMGs. Needle EMGs are invasive procedures that provide 

information about the function of the muscles and nerves in the body. 

Depending on the patient’s symptoms, a needle is inserted into muscles in 

the arm, leg, neck, or back. For example, patients with lower back pain 

may experience nerve pain from herniated discs. In this case, a needle 

EMG can evaluate the severity of the nerve damage caused by disc 

herniations. Results from needle EMGs provide information about the 

integrity of the connection between a nerve and its muscle as well as the 

integrity of the muscle itself. Typically, physicians trained specifically in 

electrodiagnostic medicine perform and interpret the results from the 

needle EMG. 

Typically, physicians perform NCTs along with needle EMGs to detect, 

measure and confirm the extent of nerve damage.5,6 When performed 

together, these tests can determine the source of nerve pain and damage 

and whether such pain is related to peripheral nerve disease. However, 

when physicians use NCTs without integrating needle EMG findings, the 

results may be misleading, potentially causing important diagnoses to be 

missed.7 

4

 American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM), 

Model Policy for Needle Electromyography and Nerve Conduction Studies, 

December 2011. Accessed at http://www.aanem.org/getmedia/4258c924-358e-42cea64e-1c6a935f2e2e/Model_Policy_NCS_EMG_12312011.pdf.aspx on June 7, 2012. 5

 AANEM, Proper Performance and Interpretation of Electrodiagnostic Studies, 

January 2006. Accessed at http://www.aanem.org/getmedia/9b4fa3d5-c127-4c3d-9296-

b650e443b2cc/ProperPerformance.pdf.aspx on July 2, 2012. 6

 Needle EMGs are optional when diagnosing carpal tunnel syndrome. American 

Association of Electrodiagnostic Medicine (now AANEM), Practice Parameter for 

Electrodiagnostic Studies in Carpal Tunnel Syndrome: Summary Statement, June 2002. 

Accessed at http://www.aanem.org/getmedia/7ddc9ef9-ee91-4b48-9c1a-53454313001e/ 

CTS.pdf.aspx on December 23, 2013. 7

 Ibid. 

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Medicare Payment for Electrodiagnostic Tests 

Medicare Part B pays for electrodiagnostic tests that are medically 

reasonable and necessary, and performed by physicians or by licensed, 

certified nonphysician personnel under appropriate physician 

supervision.8, 9

 Further, Medicare requires that diagnostic tests, including 

electrodiagnostic tests, be ordered by a physician or other qualified 

nonphysician practitioner who treats a Medicare patient for a specific 

medical problem and who uses the results of those tests to manage the 

patient’s medical condition.10 

The Medicare fee schedule for physicians sets payment rates for 

electrodiagnostic tests on the basis of the location where the physician 

performed the service.11 In 2011, Medicare’s payment amounts for NCTs 

ranged from $46 to $84 and its payment amounts for needle EMGs ranged 

from $57 to $174. 

Medicare Claims Processing and Program Safeguards 

The Centers for Medicare & Medicaid Services (CMS) uses local 

contractors, known as Medicare Administrative Contractors (MAC) to 

manage payments for Part B services. CMS and its contractors develop 

guidance and implement program safeguards to ensure the integrity of 

these services. For example, MACs can develop local coverage 

determinations (LCDs) that establish billing and coding guidelines in their 

coverage areas when there is no National Coverage Determination (NCD) 

or when there is a need to further define an NCD. To illustrate, MACs can 

establish LCDs that set utilization limits or clinical requirements for 

specific types of electrodiagnostic test claims in their coverage areas. 

These coverage rules can vary across MAC jurisdictions.12 

Additionally, LCDs inform physicians as to the correct use of modifiers 

and diagnoses on a claim. For example, some LCDs state that modifier 59 

should be added to a claim if the physician is conducting needle EMG 

8 Social Security Act § 1862(a)(1)(A), 42 U.S.C. § 1395y(a)(1)(A). 

9

 Medicare does not pay for electrodiagnostic services performed by chiropractors.
 

42 CFR § 410.21(b)(2); CMS, Medicare Benefits Policy Manual, Pub. No. 100-02, 

ch. 15, § 30.5.
 10 42 CFR § 410.32. 

11 Social Security Act § 1848, 42 U.S.C. 1395w-4. The Medicare physician fee schedule 

is derived using a resource-based relative value scale, which includes three resource 

components: (1) total physician work, (2) practice expenses, and (3) malpractice 

expenses. These payment rates are based on relative value units, adjusted for geography, 

and multiplied by a national conversion factor to derive dollar amounts. 12 CMS, A/B MAC Jurisdictions. Accessed at http://www.cms.gov/Medicare/MedicareContracting/MedicareContractingReform/PartAandPartBMACJurisdictions.html on 

June 22, 2012. All 12 A/B MAC jurisdictions were operational as of September 2013. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 3 
 

 

 

 

 

 

 

 

 

 

 

 

testing on more than one limb during the same day.13 Further, since 

physician exams are typically performed with electrodiagnostic tests, 

some LCDs state that modifier 25 should be added to a claim if a separate, 

identifiable physician visit is billed by the same physician on the same 

day. 

CMS also uses what it calls “medically unlikely edits” (MUEs) to reduce 

the paid-claims error rate for Part B claims. For example, an MUE may 

establish the maximum units of service for which a physician can bill 

under most circumstances for a single patient on the same day.14 In 2011, 

CMS had an MUE stating that the maximum “units of service” (in this 

case, the maximum number of tests) for a single NCT (procedure code 

95905) were two tests for a patient on the same day.15, 16 

Further, MACs may adopt practice guidelines developed by medical 

organizations to determine whether Medicare will cover an 

electrodiagnostic service. For example, several MACs have adopted 

AANEM guidelines stating that a needle EMG should be performed by a 

physician with special training in electrodiagnostic medicine, usually a 

physiatrist or neurologist.17 Physiatrists and neurologists receive formal 

13 Modifiers 25 and 59 are used to identify procedures that are typically not separately 

payable to make them eligible for separate payment. Under certain circumstances, it may 

be appropriate for these procedures to be paid for separately. For example, modifier 25 is 

used to indicate that a distinct evaluation and management (E/M) service was performed 

by the same physician on the same day as an NCT or needle EMG. Modifier 59 is used to 

indicate that a distinct, non-E/M service was performed by the same physician on the 

same day as an NCT or needle EMG at a different session, at a different anatomical site, 

or on a different organ system. 

14 An edit is an automated system process to ensure proper payment of claims. An MUE 

flags claims for services or combinations of services that are unlikely to be medically 

appropriate. CMS, Medically Unlikely Edits. Accessed at http://www.cms.gov/ 

Medicare/Coding/NationalCorrectCodInitEd/MUE.html on June 20, 2012. 15 Not all procedure codes have an MUE. Units of service for procedure code 95905 are 

based on each extremity (i.e., limb) tested, whereas units of service for other NCT codes 

(e.g., 95900) are based on each nerve tested. AANEM has recommendations for the 

maximum number of electrodiagnostic tests considered reasonable to diagnose a patient’s 

condition. In 2012, CMS worked with professional associations, including AANEM, to 

allow physicians to use revised CPT codes on claims that indicate the number of 

electrodiagnostic tests that were performed. However, CMS did not implement any edits 

to enforce AANEM recommendations about the number of tests. 

16 The five character codes and descriptions included in this report are obtained 

from Current Procedural Terminology (CPT®), copyright 2012 by the American 

Medical Association (AMA). CPT is developed by the AMA as a listing of 

descriptive terms and five character identifying codes and modifiers for reporting 

medical services and procedures. Any use of CPT outside of this design should refer 

to the most current version of the Current Procedural Terminology available from 

AMA. Applicable FARS/DFARS apply. 

17 AANEM, Who is Qualified to Practice Electrodiagnostic Medicine? May 1999. 

Accessed at http://www.aanem.org/getmedia/f96400ac-6534-4f9f-bddc-21231e241e0c/ 

who_is_qualified.PDF.aspx on June 6, 2012. 

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training in the diagnosis and treatment of neuromuscular diseases, and 

they are trained in the administration and interpretation of 

electrodiagnostic tests. Providers who are generally not considered to 

have special training in nerve disorders include primary care physicians, 

internists, chiropractors, orthopedists, podiatrists, and dermatologists.18, 19 

Additionally, CMS produces comparative billing reports (CBRs) for 

Part B items and services to help physicians prevent future improper 

billings and payments.20 These reports compare physicians’ billing and 

payment patterns to those of their peers in their respective States and 

across the Nation.21 As of November 2013, CMS’s contractor had issued 

initial CBRs on eight topics, including electrodiagnostic testing. The 

contractor had also issued followup CBRs on four of those eight topics, 

but it had not issued one on electrodiagnostic testing. The purpose of a 

followup CBR is to present comparisons to the providers who received the 

initial CBR; the followup CBR uses more recent data. In the CBR for 

electrodiagnostic testing, the measures of analysis were (1) the average 

number of services paid per beneficiary for NCTs and needle EMGs, 

(2) the amount paid to the provider for NCTs and needle EMGs, and 

(3) the percentage of NCTs paid for without a needle EMG on the same 

claim. 

Related Office of Inspector General Work 

This is OIG’s first evaluation on electrodiagnostic tests. However, 

previous OIG work has documented growth in other types of diagnostic 

imaging tests covered under Medicare Part B and has raised concerns 

about the appropriateness of those services.22, 23 For example, OIG 

18 AANEM, Model Policy for Needle Electromyography and Nerve Conduction Studies, 

December 2011. AANEM policy states that nonphysicians, such as physical therapists, 

chiropractors, and physician assistants, do not have appropriate training and knowledge 

to perform and interpret NCTs and needle EMGs, although they may perform NCTs 

under direct physician supervision. 

19 The American Board of Electrodiagnostic Medicine (ABEM), an independent 

credentialing body established by AANEM, administers an annual examination to 

evaluate the specialized knowledge and abilities of technologists trained in NCTs. 

AANEM, AANEM News. Accessed at http://www.aanem.org/getmedia/9970eb4f-fd3b4fff-961f-963b238390be/16.pdf.aspx on July 3, 2012. 20 Safeguard Services, LLC, CBR011–020 Frequently Asked Questions. Accessed at 

http://www.safeguard-servicesllc.com/cbr/faqs2.asp#cbr011 on June 5, 2012. CMS, 

through Safeguard Services, issued a comparative billing report for electrodiagnostic tests 

in December 2011 to a sample of 4,241 physicians. The sample typically excludes 

neurologists, physiatrists, and independent diagnostic testing facilities. The results of 

physicians’ CBRs are not publicly available. 21 Safeguard Services, LLC, Comparative Billing Report Services Overview. Accessed at 

http://www.safeguard-servicesllc.com/cbr/default.asp on June 5, 2012.
 22 OIG, Growth in Advanced Imaging Paid Under the Medicare Physician Fee Schedule,
 

OEI-01-06-00260. October 2007. 

23 OIG, Medicare Part B Billing for Ultrasound, OEI-01-08-00100. July 2009. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 5 
 

 

 

 

identified 20 counties that accounted for $336 million in questionable 

billing on ultrasound services in 2007. CMS concurred with OIG’s 

recommendation for it to monitor ultrasound claims data to detect 

questionable billing and take action when physicians bill for high numbers 

of questionable claims for ultrasound services. 

Additionally, OIG determined the extent to which use of modifier 25 (i.e., 

billing for a significant, separately identifiable evaluation and 

management (E/M) service by the same physician on the same day as 

another procedure) met Medicare program requirements in 2002.24 Of the 

450 claims with modifier 25 selected for medical review, 35 percent did 

not meet program requirements. 

Further, OIG determined whether providers used modifier 59 (i.e., billing 

for a significant, separately identifiable non-E/M service by the same 

physician on the same day as another procedure) inappropriately during 

fiscal year 2003.25 Of the 350 claims with modifier 59 selected for 

medical review, 40 percent did not meet program requirements. CMS 

concurred with OIG’s recommendations for it to work with its contractors 

to reduce the number of claims submitted using modifiers 25 and 59 that 

do not meet program requirements. 

METHODOLOGY 

Data Collection and Analysis 

We analyzed 2011 electrodiagnostic claims from 100-percent paid claims 

from CMS’s National Claims History (NCH) Carrier File. We analyzed 

approximately 3 million claims for NCTs and needle EMGs billed by 

21,663 physicians in 2011. We also analyzed all of these physicians’ 

2011 Part B claims from CMS’s NCH Carrier File. 

Identification of Physicians With Questionable Billing 

We developed seven measures of questionable billing on the basis of past 

OIG work and fraud investigations related to electrodiagnostic tests, as 

well as input from CMS staff and AANEM.26 We considered a physician’s 

billing to be unusually high, or questionable, on each of the seven 

measures if it was greater than the 75th percentile plus 1.5 times the 

24 For example, see OIG, Use of Modifier 25, OEI-07-03-00470. November 2005. 25 For example, see OIG, Use of Modifier 59 to Bypass National Correct Coding 

Initiative Edits, OEI-03-02-00771. November 2005. 26 We also analyzed electrodiagnostic test payments that were made inappropriately to 

211 physicians because on the corresponding claims, the physicians did not list diagnosis 

codes that covered electrodiagnostic services. These claims totaled $92,464 (or 

0.02 percent) of the total Medicare-allowed amounts for electrodiagnostic tests in 2011. 

We will refer these physicians to CMS for appropriate action. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 6 
 

 

 

 

 

 

 

interquartile range.27 Although some of this billing may be legitimate, 

physicians who have an unusually high amount of questionable billing 

warrant further scrutiny. 

We classified physicians into two groups on the basis of their specialty to 

ensure that physicians’ billing was compared to that of their peers. That is 

to say, we accounted for individuals who have special training in 

electrodiagnostic medicine, and therefore may see more patients who 

require electrodiagnostic testing, and may bill for more of these tests. One 

group consisted of neurologists and physiatrists, and the second group 

consisted of the remaining physicians in other specialties.28 In 2011, 

Medicare paid $373 million to 11,292 neurologists and physiatrists for 

electrodiagnostic tests. Additionally, in 2011, Medicare paid 

approximately $113 million to 10,371 physicians in other specialties for 

electrodiagnostic tests. 

For each measure of questionable billing, we included physicians whom 

Medicare paid for five or more electrodiagnostic tests.29 We also 

calculated the Medicare payment for each physician’s claim that was 

associated with questionable billing. The seven measures of questionable 

billing we developed were: 

Physicians with an unusually high percentage of electrodiagnostic test 

claims using modifier 59. For each physician, we determined the 

percentage of electrodiagnostic test claims that had modifier 59. This 

modifier is used to bill for a significant, separately identifiable non-E/M 

service by the same physician on the same day as another procedure. 

However, payments for both services are appropriate only under certain 

circumstances. Past OIG studies have found that some physicians and 

providers used this modifier to increase payments inappropriately.30 

Physicians with an unusually high percentage of electrodiagnostic test 

claims using modifier 25. For each physician, we determined the 

percentage of electrodiagnostic test claims that had modifier 25. This 

27 This is a standard exploratory method for identifying members of a population with 

unusually high values on a given statistic compared to the rest of the population when no 

established benchmarks exist. For each measure of questionable billing, this method was 

used to establish separate thresholds for the two groups of physicians. See J. W. Tukey, 

Exploratory Data Analysis, Addison-Wesley, 1977. 28 Chiropractors were analyzed separately to determine inappropriate billing, and we 

found that none received payment for electrodiagnostic tests in 2011. 

29A total of 280 physicians with questionable billing billed for fewer than 

5 electrodiagnostic tests in 2011. These physicians represented 5.35 percent of 

physicians with questionable billing and approximately $39,590 (or .008 percent) of the 

total Medicare-allowed amounts for electrodiagnostic tests in 2011. 

30 For example, see OIG, Use of Modifier 59 to Bypass National Correct Coding 

Initiative Edits, OEI-03-02-00771. November 2005. 

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modifier is used to bill for a significant, separately identifiable E/M 

service by the same physician on the same day as another procedure. 

However, payments for both services are appropriate only under certain 

circumstances. Past OIG studies have found that some physicians and 

providers used this modifier to increase payments inappropriately.31 

Physicians with an unusually high percentage of electrodiagnostic test 

claims. For each physician who was not a neurologist or physiatrist, we 

determined the percentage of electrodiagnostic test claims compared to all 

of their other Part B items and service claims. High billing of 

electrodiagnostic tests by physicians in specialties other than neurology 

and physiatry is questionable because they may be overutilizing these tests 

to evaluate beneficiaries or billing for services that were never performed. 

Physicians with an unusually high percentage of electrodiagnostic test 

claims that did not include both an NCT and a needle EMG test. For each 

physician, we determined the percentage of electrodiagnostic test claims 

that did not have both an NCT and a needle EMG on the same claim (i.e., 

claims that included one but not the other). High billing of 

electrodiagnostic tests with such claims is questionable because these two 

tests are typically performed together.32 However, according to AANEM, 

needle EMGs are optional when diagnosing carpal tunnel syndrome.33 

Therefore, we did not count a physician’s claims for an NCT performed 

without a needle EMG as questionable when the diagnosis code on the 

claim was carpal tunnel syndrome (i.e., International Classification of 

Disease Coding (ICD) 354.0). 

Physicians with an unusually high average number of miles between the 

physicians’ and beneficiaries’ locations. For each physician, we 

determined the average number of miles between the physician’s practice 

location and beneficiaries’ mailing addresses. Physicians with an 

unusually high average number of miles between the two are questionable 

because they may be billing for services that were not medically necessary 

or were never performed. 

Physicians with an unusually high percentage of beneficiaries for whom at 

least three physicians billed Medicare for electrodiagnostic tests. For 

each physician, we determined the percentage of beneficiaries for whom at 

31 For example, see OIG, Use of Modifier 25, OEI-07-03-00470. November 2005. 32 AANEM, Proper Performance and Interpretation of Electrodiagnostic Studies, 

January 2006. Accessed at http://www.aanem.org/getmedia/9b4fa3d5-c127-4c3d-9296-

b650e443b2cc/ProperPerformance.pdf.aspx on July 2, 2012. 33 AANEM, Practice Parameter for Electrodiagnostic Studies in Carpal Tunnel 

Syndrome: Summary Statement, June 2002. Accessed at 

http://www.aanem.org/getmedia/7ddc9ef9-ee91-4b48-9c1a-53454313001e/CTS.pdf.aspx 

on December 23, 2013. 

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least three physicians billed Medicare for electrodiagnostic tests in 2011.34 

When multiple physicians bill for services provided to the same 

beneficiary in a given period, there is potential for fraud (i.e., 

beneficiary-sharing). 

Physicians with an unusually high average number of electrodiagnostic 

test claims for the same beneficiary on the same day. For each physician, 

we determined the average number of electrodiagnostic test claims 

submitted for the same beneficiary on the same day in 2011.35 A high 

number of electrodiagnostic claims for the same beneficiary on the same 

day by the same physician is questionable because the physician may be 

overutilizing electrodiagnostic tests to evaluate the beneficiary on the 

same day, or billing for services that were never performed. 

We also determined whether physicians with questionable billing received 

CBRs on electrodiagnostic testing in 2011. To do this, we matched the 

National Provider Identifiers of physicians with questionable billing to 

those of physicians who received CBRs in 2011. These CBRs were sent to 

physicians who billed for electrodiagnostic tests in 2010 to help them 

prevent future improper billing and payments. We calculated the total 

number of physicians with questionable billing who received CBRs and 

determined the payments for questionable billing for these physicians. 

Geographical Analysis of Physicians With Questionable Billing 

We determined the locations of physicians with questionable billing in 

2011. To do this, we identified each physician’s Core Base Statistical Area 

(CBSA) on the basis of the ZIP Code listed on the physician’s claims for 

electrodiagnostic tests.36 CBSAs may be categorized as metropolitan or 

micropolitan. We determined the percentage of physicians in each 

metropolitan area who had questionable billing and identified the 

metropolitan areas with the highest concentrations of physicians with 

questionable billing. 

In metropolitan areas with the highest number of physicians with 

questionable billing, we calculated the total number of physicians, the 

percentage of physicians with questionable billing, and the Medicare 

34 When a physician has an unusually high percentage of beneficiaries for whom at least 

three physicians billed Medicare for electrodiagnostic tests, this may indicate that 

physicians have worked together to “share” beneficiaries. Beneficiary-sharing is a 

common fraud scheme and may involve cooperation among managers, physicians, and 

marketers to solicit beneficiaries or beneficiary Medicare numbers. 

35 We ensured that our threshold met or exceeded the highest total number of tests 

recommended by AANEM, which was 14 tests. 

36 A CBSA is a region around an urban center that has at least 10,000 people. U.S.
 

Census Bureau, Metropolitan and Micropolitan Statistical Areas. Accessed at 

http://www.census.gov/population/metro/ on January 31, 2013. 

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payments to physicians with questionable billing in these areas. 

Additionally, for each metropolitan area with physicians with questionable 

billing, we identified the number of physicians with at least three measures 

of questionable billing and the Medicare payments to these physicians. 

Limitations 

We did not conduct a medical record review to determine whether the 

services we identified as being associated with questionable billing were 

inappropriate or fraudulent. Further, these characteristics are not intended 

to be a comprehensive set of measures for identifying questionable billing 

for electrodiagnostic tests. 

Standards 

This study was conducted in accordance with the Quality Standards for 

Inspection and Evaluation issued by the Council of the Inspectors General 

on Integrity and Efficiency. 

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FINDINGS 

In 2011, 4,901 physicians had questionable billing for 

Medicare electrodiagnostic tests totaling $139 million 

A total of 4,901 physicians met or exceeded the threshold for at least one 

measure of questionable billing, representing 23 percent of the 

21,663 physicians who billed for electrodiagnostic services in 2011. 

Table 1 shows the number and percentage of physicians by the number of 

questionable billing measures for which physicians exceeded thresholds. 

These questionable billings accounted for 31 percent ($139 million of 

$486 million) of the Medicare payments for electrodiagnostic tests in 

2011. 

Of the physicians with questionable billing, 49 percent (2,387 of 4,901) 

were neurologists and physiatrists who, have special training in 

electrodiagnostic medicine, and therefore may see more patients who 

require electrodiagnostic testing, and may bill for more of these tests. The 

remaining 51 percent (2,514 of 4,901) were physicians in other specialties. 

Physicians with questionable billing in other specialties largely 

represented internal medicine, family practice, orthopedic surgery, and 

podiatry (i.e., recognized by AANEM as specialties that are generally not 

considered to have expertise in electrodiagnostic medicine). Appendix A 

shows the number and percentage of physicians with questionable billing 

in each specialty. 

Overall, 13 percent (644 of 4,901) of physicians with questionable billing 

exceeded the thresholds for two or more measures of questionable billing. 

Appendix B shows the number and percentage of physicians by the 

number of measures of questionable billing for which physicians exceeded 

thresholds in each specialty group (i.e., neurologists and physiatrists, and 

physicians in other specialties). 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 11 
 

 

 

 

 

 

Table 1. Number and Percentage of Physicians Who Exceeded Thresholds 

for Questionable Billing, 2011 

Number of Measures of 

Questionable Billing for 

Which Physicians 

Exceeded Thresholds 

Number of 

Physicians 

Percentage of 

Physicians 

0 16,762 77% 

1 4,257 20% 

2 572 3% 

3 72 <1% 

4 or more 0 <1% 

 Total* 21,663 100% 

*The percentage column sum does not equal total because of rounding. 

Source: OIG analysis of 2011 NCH Carrier file.
 

For each measure of questionable billing, Table 2 shows the total number 

of physicians who met or exceeded the threshold for unusually high billing 

and the associated Medicare payments. Appendix C shows the median 

(i.e., the value at which 50 percent of all physicians billed for that 

measure); the threshold that indicated unusually high billing; the range of 

unusually high billing; and the number of physicians in each specialty 

group with unusually high billing. 

Table 2. Physicians With Unusually High Billing by Each Measure of 

Questionable Billing, 2011* 

Measure of Questionable Billing 

Physicians With Unusually High 

Billing 

Total Number of 

Physicians 

Meeting or 

Exceeding 

Threshold 

Total Medicare 

Payments 

High percentage of electrodiagnostic test claims with modifiers 

Modifier 59

 Modifier 25 

2,208 

2,156

 52

 $47 million 

$46 million

 $1 million 

High percentage of electrodiagnostic test claims from all billing for 

Part B items and services 1,155 $61 million 

High percentage of electrodiagnostic test claims that did not include 

both an NCT and needle EMG test 907 $19 million 

High average number of miles between physicians’ and beneficiaries’ 

locations 700 $15 million 

High percentage of beneficiaries for whom at least three physicians 

billed for electrodiagnostic tests 346 $ 3 million 

High average number of electrodiagnostic test claims for the same 

beneficiary on the same day 334 $20 million

 Total** 4,901 $139 million 

* The medians, thresholds, and range of billing for each measure of questionable billing, by specialty group, are listed in Appendix C.
 

** The sums of the numbers do not equal the totals because some physicians had multiple measures of questionable billing.
 

Source: OIG analysis of 2011 NCH Carrier File. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 12 
 

 

 

 

 

 

 

 

 

 

In 2011, 2,208 physicians billed for an unusually high 

percentage of electrodiagnostic tests using modifiers 

In 2011, 2,208 physicians billed for an unusually high percentage of 

electrodiagnostic tests using modifiers 59 and/or 25 on their claims. These 

claims accounted for $47 million of the 2011 payments for 

electrodiagnostic tests. Billing for a high percentage of electrodiagnostic 

tests using modifiers may indicate that a physician is using the modifiers 

to increase payments inappropriately. 

A total of 2,156 physicians billed for an unusually high percentage of 

electrodiagnostic tests using modifier 59 (i.e., billing for a significant, 

separately identifiable non-E/M service by the same physician on the same 

day as another procedure). Of all these physicians, 19 percent 

(405 of 2,156) always billed for electrodiagnostic tests using modifier 59.37 

A total of 52 physicians billed for an unusually high percentage of 

electrodiagnostic tests using modifier 25 (i.e., billing for a significant, 

separately identifiable E/M service by the same physician on the same day 

as another procedure). Of 21,663 physicians who billed for 

electrodiagnostic tests in 2011, these 52 were the only physicians who 

billed for electrodiagnostic tests using modifier 25.38 

In 2011, 1,155 physicians billed for an unusually high 

percentage of electrodiagnostic tests 

In 2011, 1,155 physicians in specialties other than neurology or physiatry 

billed for an unusually high percentage of electrodiagnostic tests 

compared to all of their billing for Part B items and services. These 

claims accounted for $61 million of the 2011 payments for 

electrodiagnostic tests. For example, 23 physicians billed only for 

electrodiagnostic tests and no other Part B items and services in 2011, 

totaling $685,000.39 For physicians in specialties other than neurology and 

physiatry, a high percentage of billing for electrodiagnostic tests may 

indicate that the physicians are submitting claims for services that were 

not medically necessary or were never provided to the beneficiary. 

37 The three specialties with the highest numbers of physicians who always billed using 

modifier 59 were internal medicine (89 of 405), neurology (78 of 405), and family 

practice (61 of 405). 

38 The majority of physicians who billed for electrodiagnostic test claims using 

modifier 25 were neurologists (30 of 52) and physiatrists (17 of 52). 

39 These physicians represented the following specialties: physical therapist in private 

practice (13 of 23); independent diagnostic testing facility (5 of 23); family practice 

(2 of 23); neurosurgery; pediatric medicine, and single or multispecialty clinic or group 

practice. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 13 
 

 

 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 14 

In 2011, 907 physicians billed for an unusually high percentage 

of electrodiagnostic tests that did not include both an NCT and 

needle EMG test 

In 2011, 907 physicians billed for an unusually high percentage of 

electrodiagnostic tests that did not include both an NCT and a needle 

EMG test. These claims accounted for $19 million of the 2011 payments 

for electrodiagnostic tests. Typically, when NCTs are used alone, without 

integrating needle EMG findings, the results may be misleading, 

potentially causing important diagnoses to be missed.40 

All of the physicians whom we identified as having an unusually high 

percentage of electrodiagnostic tests that did not include both an NCT and 

a needle EMG test were neurologists or physiatrists. None of the 

physicians in other specialties were identified statistically as having 

“unusually high” billing because they almost always billed for 

electrodiagnostic tests without having both an NCT and a needle EMG test 

on the same claim; the median for such physicians was 85 percent. These 

physicians represented approximately $72 million in payments.41 Because 

there was no distribution in billing for this measure of questionable billing 

among non-neurologist and nonphysiatrist physicians, we identified no 

physicians in this category as billing for unusually high percentages of 

electrodiagnostic tests that did not include both an NCT and needle EMG 

test. However, this billing pattern among non-neurologist and 

nonphysiatrist physicians raises concerns. 

In 2011, 700 physicians billed for electrodiagnostic tests for 

beneficiaries from locations an unusually high average 

number of miles away 

In 2011, 700 physicians billed for electrodiagnostic tests for beneficiaries 

who resided an unusually high average number of miles from the 

physicians’ practice locations. These claims accounted for $15 million of 

the 2011 payments for electrodiagnostic tests. For example, we found that 

one general practitioner in Indianapolis, Indiana, billed for an 

electrodiagnostic test for a beneficiary who resided nearly 2,000 miles 

away, in McKinleyville, California. This physician’s 27 other beneficiaries 

resided an average of 1,785 miles away.42 

A high average number of miles between physicians’ and beneficiaries’ 

locations may indicate that a physician is billing for electrodiagnostic tests 

that were not medically necessary or were never provided to the 

40 NCTs performed without a needle EMG may be acceptable for some diagnoses. 41 The Tukey method requires a distribution or variability in billing to identify outliers. 

42 Nearly all (26 of 28) of these beneficiaries resided in California. 
 

 

 

 

 

 

 

 

 

beneficiary. Further, beneficiaries with conditions that may cause nerve 

damage, such as diabetes or carpal tunnel syndrome, would not be 

expected to travel such long distances for electrodiagnostic tests. 

In 2011, 346 physicians billed for an unusually high percentage 

of beneficiaries for whom at least three physicians also billed 

for electrodiagnostic tests 

In 2011, 346 physicians billed for an unusually high percentage of 

beneficiaries for whom at least three physicians also billed for 

electrodiagnostic tests. These claims accounted for $3 million of the 

2011 payments for electrodiagnostic tests. 43 When multiple physicians 

bill for the same services provided to the same beneficiary, there is 

potential for fraud (i.e., beneficiary-sharing). For example, 100 percent of 

the beneficiaries for 28 physicians had electrodiagnostic test claims from 

at least 3 physicians in 2011.44 

In 2011, for about 95 percent of beneficiaries, one physician submitted 

claims for their electrodiagnostic tests. For about 5 percent of 

beneficiaries, two physicians submitted claims for their electrodiagnostic 

tests. For less than 1 percent of beneficiaries, three or more physicians 

submitted claims for their electrodiagnostic tests. In the case of one 

beneficiary, nine different physicians billed Medicare for this individual’s 

electrodiagnostic tests in 2011. 

In 2011, 334 physicians billed for an unusually high average 

number of electrodiagnostic tests for the same beneficiary on 

the same day 

In 2011, 334 physicians billed for an unusually high average number of 

electrodiagnostic tests for the same beneficiary on the same day.45 These 

claims accounted for $20 million of the 2011 payments for 

electrodiagnostic tests. For example, 6 physicians billed for an average of 

32 electrodiagnostic tests for the same beneficiary on the same day, almost 

5 times the median number of 7 electrodiagnostic tests.46 Billing for 

multiple electrodiagnostic tests for the same beneficiary on the same day 

43 Thirty providers who had an unusually high percentage of beneficiaries for whom other 

providers billed Medicare for electrodiagnostic tests also had an unusually high average 

number of miles between their and beneficiaries’ locations. 44 The majority of these providers had the following specialties: family practice 

(6 of 28), internal medicine (6 of 28), and orthopedic surgery (4 of 28). 

45 Sixty-seven physicians who billed for an unusually high percentage of 

electrodiagnostic test claims using modifiers also billed for an unusually high average 

number of electrodiagnostic test claims for the same beneficiary on the same day. 

46 The six physicians represented the following specialties: family practice, internal 

medicine, nurse practitioner, and physician assistant. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 15 
 

 

 

 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 16 

 

may indicate that a physician is billing for electrodiagnostic tests that were 

not medically necessary or were never provided to the beneficiary. 

Approximately 20 percent of physicians with questionable 

billing in 2011 received a CBR on the basis of their 2010 billing 

for electrodiagnostic tests 

CMS issues CBRs that are designed to compare a provider’s billing and 

payment patterns to those of his or her peers across the Nation. 

Additionally, CBRs are intended to proactively educate providers and help 

them identify and prevent future errors in their billing practices. 

In late 2011, CMS and its contractors issued CBRs to 4,241 physicians 

who billed for NCTs and needle EMGs in 2010. The CBR analysis 

measures include some of the same analysis and measures of questionable 

billing that we used in this report. The primary differences, however, are 

that CMS typically excludes neurologists and physiatrists from its 

analysis, and that its measures are not intended to identify physicians who 

had unusually high billing.47 

A total of 1,095 physicians who received a CBR in 2011 on the basis of 

their 2010 billing also had questionable billing for electrodiagnostic tests 

in 2011, totaling approximately $34 million. The remaining 78 percent 

(3,806 of 4,901) of physicians whom we identified as having questionable 

billing did not receive a CBR in 2011.48 Table 3 shows the number of 

physicians with questionable billing, whether they received CBRs, and the 

questionable Medicare payments. 

47 Although CMS’s methods for creating CBRs for electrodiagnostic tests state that it 

excludes neurologists and physiatrists, we found that 12 physicians in the neurologist and 

physiatrist specialty group who had questionable billing received CBRs. 

48 These physicians may not have billed for electrodiagnostic tests in 2010, so they would 

not have received a CBR in 2011. 
 

 

Table 3. Physicians With Questionable Billing and CBRs in Each Specialty 

Group, 2011 

Number of 

Physicians 

With 

Questionable 

Billing and 

CBRs 

Medicare 

Payments* 

Number of 

Physicians With 

Questionable 

Billing and no 

CBRs 

Medicare 

Payments 

Physicians in Other 

Specialties 1,083 $33 million 1,429 $37 million 

Neurologists and 

Physiatrists 12 $786,512 2,377 $68 million

 Total 1,095 $34 million 3,806 $105 million 

* The column sum does not equal total because of rounding. 

Source: OIG analysis of 2011 NCH Carrier File. 

Thirty-eight percent of physicians with questionable 

billing for electrodiagnostic tests were in

10 metropolitan areas 

Certain metropolitan areas had a higher percentage of physicians with 

questionable billing for electrodiagnostic tests than did the Nation as a 

whole, which had 23 percent. Physicians with questionable billing for 

electrodiagnostic tests in these 10 metropolitan areas made up 38 percent 

(1,883 of 4,901) of all physicians with questionable billing. The 

New York, Los Angeles, and Houston areas had the highest Medicare 

payments associated with questionable billing. Specifically, Medicare 

paid $27 million associated with questionable billing to 737 physicians in 

the New York area. Medicare paid approximately $12 million associated 

with questionable billing to 219 physicians in the Los Angeles area, and 

approximately $6 million associated with questionable billing to 

156 physicians in the Houston area. 

Table 4 shows for 10 metropolitan areas the number of physicians with 

questionable billing, the total number of physicians, the percentage of 

physicians with questionable billing, and the Medicare payments for 

physicians with questionable billing. Appendix D includes the number of 

physicians with questionable billing in these metropolitan areas 

categorized by specialty group. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 17 
 

 

 

 

Table 4. Metropolitan Areas With the Highest Number of Physicians With 

Questionable Billing, 2011 

Metropolitan 

Area 

Total Number of 

Physicians With 

Questionable 

Billing 

Total Number of 

Physicians 

Percentage of 

Physicians With 

Questionable Billing 

Questionable

 Medicare

 Payments 

New York, NY 737 2,745 27% $26,625,059 

Los Angeles, CA 219 695 32% $11,581,976 

Houston, TX 156 395 39% $5,983,651 

Miami, FL 193 566 34% $4,945,350 

Dallas, TX 109 345 32% $3,168,436 

Detroit, MI 98 483 20% $3,717,991 

Chicago, IL 97 644 15% $3,233,386 

Washington, DC 96 403 24% $1,995,174 

Phoenix, AZ 91 306 30% $3,091,317 

Baltimore, MD 87 277 31% $1,674,583 

Nation 4,901 21,663 23% $139 million 

Source: OIG analysis of physician data for electrodiagnostic tests, 2011. 

Additionally, within the group of 4,901 physicians who met or exceeded 

the threshold for at least one measure of questionable billing, 72 

physicians met or exceeded the thresholds for three measures of 

questionable billing. Medicare paid $4 million associated with 

questionable billing to such physicians. The metropolitan areas with the 

highest numbers of such physicians were Las Vegas, Nevada; New York, 

New York; and Baltimore, Maryland; in these three areas, these physicians 

received a total of $880,000 associated with questionable billing. 

Appendix E lists the geographical areas of physicians who met or 

exceeded the thresholds for three measures of questionable billing in 2011. 

Appendix F lists the geographical areas of the top 10 physicians with 

questionable billing in 2011. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 18 
 

 

CONCLUSION AND RECOMMENDATIONS 

We found that 4,901 physicians had questionable billing for 

electrodiagnostic tests with Medicare payments totaling $139 million in 

2011. While there may be legitimate reasons for some of this billing, all 

of these physicians warrant further scrutiny. The majority of these 

physicians had an unusually high percentage of claims with modifiers, 

which allow physicians to receive payments for services that are typically 

not separately payable. Previous OIG studies also found that some 

physicians and providers use modifiers to increase payments 

inappropriately. For example, a 2005 OIG evaluation found that 

$59 million was paid improperly for claims using modifier 59. Further, 

many of the non-neurologist and nonphysiatrist physicians whom we 

identified as having questionable billing had an unusually high percentage 

of claims for electrodiagnostic tests compared to their claims for other 

Part B items and services. Finally, physicians in the New York, 

Los Angeles, and Houston areas had the highest total questionable billing 

for Medicare electrodiagnostic tests in 2011. 

Our findings further indicate vulnerabilities in the monitoring of Medicare 

billing for electrodiagnostic tests. We found that approximately 

20 percent of the physicians with questionable billing for electrodiagnostic 

tests received CBRs in 2011 on the basis of their 2010 electrodiagnostic 

test billing. Further, nearly half of the physicians whom we identified as 

having questionable billing were neurologists and physiatrists. However, 

CMS typically does not provide CBRs on electrodiagnostic testing to 

neurologists and physiatrists. 

We recommend that CMS: 

Increase monitoring of billing for electrodiagnostic tests 

CMS should instruct its contractors (e.g., Medicare Administrative 

Contractors, Zone Program Integrity Contractors) to monitor the billing of 

electrodiagnostic tests using measures of questionable billing similar to 

those we incorporated into this study. CMS should develop thresholds for 

these measures and instruct its contractors to conduct additional reviews of 

physicians who exceed them. For example, CMS could use AANEM 

recommendations for the maximum number of electrodiagnostic tests that 

should be performed to develop edits on the number of tests billed. CMS 

could also include these measures of questionable billing in its 

fraud-prevention system. Finally, CMS should use comparative billing 

reports to identify and monitor all physicians—including neurologists and 

physiatrists—with unusually high billing for electrodiagnostic tests. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 19 
 

 

Provide additional guidance and education to physicians 

regarding electrodiagnostic tests 

CMS should update its guidance and provide additional education to 

physicians who provide electrodiagnostic tests. As part of this effort, 

CMS should educate physicians on industry guidance regarding providing 

NCTs in conjunction with needle EMGs for establishing reliable and 

accurate diagnoses. 

Take appropriate action regarding physicians whom we 

identified as having inappropriate or questionable billing 

In a separate memorandum, we will send the claims data for physicians 

with inappropriate or questionable billing to CMS for appropriate action. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 20 
 

 

 

 

AGENCY COMMENTS AND OFFICE OF INSPECTOR GENERAL 

RESPONSE 

CMS partially concurred with our first two recommendations and 

concurred with the third one. With regard to the first recommendation, 

CMS partially concurred and stated that it will evaluate the costeffectiveness of implementing new thresholds for questionable billing and 

conducting medical record reviews of physicians who exceed them. CMS 

also provided information about its efforts to monitor Medicare billing for 

electrodiagnostic tests. Specifically, CMS will share this report with its 

Recovery Auditors for possible review and overpayment recovery. CMS 

will also consider including a model that monitors for unusually high 

billing for electrodiagnostic tests in its Fraud Prevention System. Finally, 

CMS will develop CBRs on electrodiagnostic testing that include 

neurologists and physiatrists. 

With regard to the second recommendation, CMS partially concurred and 

stated that it established revised values for new codes that bundle needle 

EMG and NCT codes, which has resulted in simplified coding and savings 

to the Medicare program for these services. CMS noted that it is 

prohibited from providing guidance on the practice of medicine to 

physicians and, therefore, it may be a violation to emphasize the 

importance of providing NCTs in conjunction with needle EMGs. In 

response to CMS’s comments, we clarified this recommendation to state 

that CMS should educate physicians on industry guidance regarding 

performing and billing for these services together. We are not 

recommending that CMS provide guidance on the practice of medicine to 

physicians. 

With regard to the third recommendation, CMS concurred and will instruct 

the Supplemental Medical Review Contractor to review some or all of the 

physicians identified in this report. CMS will also ask these contractors to 

determine which of the seven questionable billing measures were the best 

predictors of improper payments. Finally, any suspicions of potential 

fraud will be referred to the appropriate Zone Program Integrity 

Contractor. 

We support CMS’s efforts to address these issues and encourage it to 

continue making progress. For the full text of CMS’s comments, see 

Appendix G. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 21 
 

 

 

APPENDIX A 

Number and Percentage of Medicare Physicians With 

Questionable Billing for Electrodiagnostic Tests in Each 

Specialty, 2011 

Specialty 

Number of 

Physicians With 

Questionable 

Billing in Each 

Specialty 

Number of 

Physicians in 

Each Specialty 

Percentage of 

Physicians With 

Questionable 

Billing in Each 

Specialty 

Neurology 1696 7050 24% 

Physiatry 693 4245 16% 

Internal Medicine 594 2742 22% 

Family Practice 461 2144 22% 

Orthopedic Surgery 211 1115 19% 

Podiatry 163 550 30% 

Interventional Pain Management 111 344 32% 

General Practice 82 229 36% 

Neurosurgery 75 192 39% 

Physician Assistant 70 249 28% 

Physical Therapist in Private Practice 68 134 51% 

Independent Diagnostic Testing Facility (IDTF) 67 86 45% 

Pain Management 61 150 41% 

Nurse Practitioner 59 266 22% 

Hand Surgery 47 135 35% 

Anesthesiology 40 170 24% 

Cardiology 37 206 18% 

Endocrinology 37 180 21% 

Rheumatology 36 284 13% 

Emergency Medicine 36 102 35% 

Nephrology 31 68 46% 

General Surgery 22 111 20% 

Pediatric Medicine 21 42 50% 

Otolaryngology 20 354 6% 

Psychiatry 19 30 63% 

Diagnostic Radiology 18 46 39% 

Colorectal Surgery (formerly Proctology) 16 92 17% 

Pulmonary Disease 16 45 36% 

Plastic and Reconstructive Surgery 14 55 25% 

Osteopathic Manipulative Medicine 11 30 37% 

Neuropsychiatry 11 18 61% 

Obstetrics/Gynecology 9 24 38% 

Gastroenterology 7 27 26% 

Hematology/Oncology 6 20 30% 

Urology 5 17 29% 

(continued on next page) 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 22 
 

 

APPENDIX A (CONTINUED) 

Number and Percentage of Medicare Physicians With 

Questionable Billing for Electrodiagnostic Tests in Each 

Specialty, 2011 

Specialty 

Number of 

Physicians With 

Questionable 

Billing in Each 

Specialty 

Number of 

Physicians in 

Each Specialty 

Percentage of 

Physicians With 

Questionable 

Billing in Each 

Specialty 

Infectious Disease 5 12 42% 

Vascular Surgery 5 13 38% 

Geriatric Medicine 4 18 22% 

Allergy/Immunology 3 9 33% 

Ophthalmology 2 4 50% 

Pathology 2 4 50% 

Sports Medicine 2 6 33% 

Thoracic Surgery 2 3 67% 

Occupational Therapist in Private Practice 2 4 50% 

Oral Surgery (Dentists Only) 1 3 33% 

Nuclear Medicine 1 1 100% 

Single or Multispecialty Clinic or Group Practice 1 4 25% 

Peripheral Vascular Disease 1 1 100% 

Addiction Medicine 1 2 50% 

Critical Care (Intensivists) 1 3 33% 

Dermatology 0 1 0% 

Audiologist (Billing Independently) 0 4 0% 

Clinical Laboratory (Billing Independently) 0 2 0% 

Preventive Medicine 0 4 0% 

Maxillofacial Surgery 0 1 0% 

Certified Clinical Nurse Specialist 0 2 0% 

Medical Oncology 0 2 0% 

Surgical Oncology 0 6 0% 

Radiation Oncology 0 1 0% 

Interventional Radiology 0 1 0%

 Total 4,901 21,663 23% 

Source: OIG analysis of physician data for electrodiagnostic tests, 2011. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 23 
 

 

 

APPENDIX B 

Number and Percentage of Medicare Physicians Who 

Exceeded Thresholds of Questionable Billing for 

Electrodiagnostic Tests by Specialty Group, 2011 

Specialty Group 

Number of Measures for 

Which Physicians Exceeded 

Thresholds of Questionable 

Billing for Electrodiagnostic 

Tests 

Number of Physicians Percentage of 

Physicians 

Neurologists and 

Physiatrists 

0 8,903 79% 

1 2,078 18% 

2 265 2% 

3 46 <1% 

4 or more 0 0%

 Total* 11,292 100% 

Physicians in Other 

Specialties 

0 7,859 76% 

1 2,179 21% 

2 307 3% 

3 26 <1% 

4 or more 0 0%

 Total* 10,371 100% 

* The sums of the percentages in the final column does not equal total because of rounding. 

Source: OIG analysis of physician data for electrodiagnostic tests, 2011. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 24 
 

 

 

APPENDIX C 

Physicians With Unusually High Billing by Each Measure of 

Questionable Billing, 2011 

Table C-1. Neurologists and Physiatrists With Unusually High Billing by 

Each Measure of Questionable Billing, 2011 

Measure of Questionable 

Billing Median 

Neurologists and Physiatrists With Unusually High Billing 

Threshold 

Range of 

Billing 

Medicare 

Billing 

Number of 

Physicians 

Exceeding 

Threshold 

High percentage of 

electrodiagnostic test claims 

with modifiers 

Modifier 59 

Modifier 25** 

2% 

0% 

48% 

0% 

48% to 100% 

<1% to 12% 

$29.9 million 

$29 million 

$994,000 

1,047 

1,000 

47 

High percentage of 

electrodiagnostic test claims 

from all billing for Part B items 

and services* 

-- -- -- -- --

High percentage of 

electrodiagnostic test claims 

that did not include both an NCT 

and needle EMG test 8% 61% 61% to 100% $18.7 million 907 

High average number of miles 

between physicians’ and 

beneficiaries’ locations 116 321 321 to 2,961 $11.7 million 358 

High percentage of beneficiaries 

for whom at least three 

physicians billed Medicare for 

electrodiagnostic tests 2% 7% 7% to 100% $ 1.5 million 256 

High average number of 

electrodiagnostic test claims on 

the same beneficiary on the 

same day*** 8 14 14 to 30 $15.9 million 181 

Total **** $68.9 million 2,389 

*Because some neurologists and physiatrists may reasonably bill for electrodiagnostic tests and have no other billing for Part 

B items and services, we did not include neurologists and physiatrists in the analysis for this characteristic. 

**The median and threshold are 0 percent for this characteristic because only 47 of 11,292 neurologists and physiatrists 

used modifier 25 on at least 1 of their 2011 electrodiagnostic test claims. All 47 of these physicians were identified using the 

Tukey method as having an unusually high percentage. 

*** Under the Tukey method, an outlier is a number greater than the 75th percentile plus 1.5 times the interquartile range. For 

this characteristic of questionable billing, the Tukey method yielded a threshold number of 13 tests. However, because 

AANEM sets at 14 the maximum number of tests considered reasonable to make a diagnosis, we used a threshold of 

14 tests. 

****The sums of the columns do not equal totals because some neurologists and physiatrists had multiple measures of 

questionable billing. 

Source: OIG analysis of physician data for electrodiagnostic tests, 2011. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 25 
 

 

APPENDIX C (CONTINUED) 

Physicians With Unusually High Billing by Each Measure of 

Questionable Billing, 2011 

Table C-2. Physicians in Other Specialties With Unusually High Billing by 

Each Measure of Questionable Billing, 2011 

Measure of Questionable Billing Median 

Physicians in Other Specialties With Unusually High Billing 

Threshold 

Range of 

Billing 

Medicare 

Billing 

Number of 

Physicians 

Exceeding 

Threshold 

High percentage of 

electrodiagnostic test claims with 

modifiers 

Modifier 59 

Modifier 25* 

0% 

0% 

42% 

0% 

42% to 100% 

<1% to 25% 

$17 million 

$17 million 

$16,000 

1,161 

1,156 

5 

High percentage of 

electrodiagnostic test claims from 

all billing for Part B items and 

services 1% 13% 13% to 100% $60.7 million 1,155 

High percentage of 

electrodiagnostic test claims that 

did not include both an NCT and 

needle EMG test ** 85% 100% 

-- -- --

High average number of miles 

between physicians’ and 

beneficiaries’ locations 111 335 335 to 2,541 $3.4 million 342 

High percentage of beneficiaries 

for whom at least three physicians 

billed Medicare for 

electrodiagnostic tests 6% 28% 28% to 100% $1.3 million 90 

High average number of 

electrodiagnostic test claims for 

the same beneficiary on the same 

day 7 19 19 to 32 $4.1 million 153 

 Total *** $69.9 million 2,512 

*The median and threshold are 0 percent for this characteristic because only 5 of 10,371 physicians with other specialties 

used modifier 25 on their 2011 electrodiagnostic test claims. All five of these physicians were identified using the Tukey 

method as having an unusually high percentage. 

** The Tukey method requires a distribution or variability in billing to identify unusual behavior. Because there was no 

distribution in billing for this measure of questionable billing among physicians in this specialty group (i.e., they almost always 

billed for NCTs without needle EMGS), no physicians were identified as billing for unusually high percentages of NCTs 

without needle EMGs. 

*** The sums of the columns do not equal total because some physicians in other specialties had multiple questionable billing 

characteristics. 

Source: OIG analysis of physician data for electrodiagnostic tests, 2011. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 26 
 

 

APPENDIX D 

Metropolitan Areas With the Highest Number of Physicians 

With Questionable Billing by Specialty Group, 2011 

Metropolitan Area 

Number of 

Neurologists and 

Physiatrists with 

Questionable Billing 

Number of 

Physicians in Other 

Specialties with 

Questionable Billing 

Total Number of 

Physicians With 

Questionable Billing 

New York, NY 243 494 737 

Los Angeles, CA 114 105 219 

Miami, FL 75 118 193 

Houston, TX 62 94 156 

Dallas, TX 79 30 109 

Detroit, MI 44 54 98 

Chicago, IL 57 40 97 

Washington, DC 47 49 96 

Phoenix, AZ 45 46 91 

Baltimore, MD 41 46 87 

Total 807 1,076 1,883

 Nation 2,387 2,514 4,901 

Source: OIG analysis of physician data for electrodiagnostic tests, 2011. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 27 
 

 

APPENDIX E 

Geographical Areas of Physicians With Three Measures of 

Questionable Billing, 2011 

Geographical Area 

Questionable 

Medicare Billing 

Number of 

Physicians With 

Multiple Measures 

of Questionable 

Billing 

Percentage of 

Physicians With 

Multiple Measures 

of Questionable 

Billing 

Las Vegas-Paradise, NV $420,083 8 11.11% 

New York-Northern New Jersey-Long Island, NY-NJ-PA $351,020 6 

8.33% 

Baltimore-Towson, MD $108,039 5 

6.94% 

Miami-Fort Lauderdale-Pompano Beach, FL $34,258 4 

5.55% 

Boston-Cambridge-Quincy, MA-NH $95,361 3 

4.17% 

Fort Collins-Loveland, CO $53,441 3 

4.17% 

Phoenix-Mesa-Glendale, AZ $3,439 3 

4.17% 

Denver-Aurora-Broomfield, CO $406,247 2 

2.78% 

Oxnard-Thousand Oaks-Ventura, CA $192,849 2 

2.78% 

Jamestown-Dunkirk-Fredonia, NY $43,838 2 

2.78% 

Detroit-Warren-Livonia, MI $32,639 2 

2.78% 

Los Angeles-Long Beach-Santa Ana, CA $16,150 2 

2.78% 

San Diego-Carlsbad-San Marcos, CA $11,482 2 

2.78% 

Houston-Sugar Land-Baytown, TX $9,451 2 

2.78% 

Cape Coral-Fort Myers, FL $698,550 1 

1.39% 

Dallas-Fort Worth-Arlington, TX $548,708 1 

1.39% 

New Orleans-Metairie-Kenner, LA $350,562 1 

1.39% 

Lansing-East Lansing, MI $142,734 1 

1.39% 

Washington-Arlington-Alexandria, DC-VA-MD-WV $136,775 1 

1.39% 

Hagerstown-Martinsburg, MD-WV $54,710 1 

1.39% 

Anchorage, AK $32,034 1 

1.39% 

St. Louis, MO-IL $29,132 1 

1.39% 

Austin-Round Rock-San Marcos, TX $28,814 1 

1.39% 

Trenton-Ewing, NJ $25,832 1 

1.39% 

Topeka, KS $23,470 1 

1.39% 

Nashville-Davidson--Murfreesboro-Franklin, TN $21,965 1 

1.39% 

New Haven-Milford, CT $18,538 1 

1.39% 

(continued on next page) 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 28 
 

 

APPENDIX E (CONTINUED) 

Geographical Areas of Physicians With Three Measures of 

Questionable Billing, 2011 

Geographical Area 

Questionable 

Medicare Billing 

Number of 

Physicians With 

Multiple Measures 

of Questionable 

Billing 

Percentage of 

Physicians With 

Multiple Measures 

of Questionable 

Billing 

Louisville-Jefferson County, KY $12,007 1 

1.39% 

Lake Havasu City-Kingman, AZ $11,969 1 

1.39% 

Toledo, OH $9,504 1 

1.39% 

Flint, MI $6,793 1 

1.39% 

McAllen-Edinburg-Mission, TX $3,766 1 

1.39% 

Chicago-Naperville-Joliet, IL-IN-WI $2,508 1 

1.39% 

San Juan-Caguas-Guaynabo, PR $1,718 1 

1.39% 

Bloomsburg-Berwick, PA $1,062 1 

1.39% 

Minneapolis-St. Paul-Bloomington, MN-WI $854 1 

1.39% 

San Angelo, TX $534 1 

1.39% 

Somerset, PA $448 1 

1.39% 

Brownsville-Harlingen, TX $430 1 

1.39% 

Rural $88,485 1 

1.39% 

Total* $4 million 72 100% 

*The sum of the percentages in the final column does not equal the total because of rounding. 

Source: OIG analysis of physician data for electrodiagnostic tests, 2011. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 29 
 

 

 

APPENDIX F 

Geographical Areas of Top 10 Physicians With Questionable 

Billing, 2011 

Physician 

Number Geographical Area 

Questionable 

Medicare 

Billing 

Physician 1 Los Angeles-Long Beach-Santa Ana, CA $3,103,642 

Physician 2 Miami-Fort Lauderdale-Pompano Beach, FL $900,513 

Physician 3 New York-Northern New Jersey-Long Island, NY-NJ-PA $769,644 

Physician 4 Brownwood, TX $732,342 

Physician 5 Cape Coral-Fort Myers, FL $698,550 

Physician 6 Los Angeles-Long Beach-Santa Ana, CA $690,872 

Physician 7 New York-Northern New Jersey-Long Island, NY-NJ-PA $597,269 

Physician 8 Bakersfield-Delano, CA $576,119 

Physician 9 Detroit-Warren-Livonia, MI $564,589 

Physician 10 New York-Northern New Jersey-Long Island, NY-NJ-PA $558,112

 Source: OIG analysis of physician data for electrodiagnostic tests, 2011. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 30 
APPENDIX G 

Agency Comments 

/<,J.IJ.VIC(J'\ (,j. DEPARTMENT OF IlEALTil & HUMAN SERVICES Centers for Medicare &Medicaid Services 

Administrator 

Washington. DC 20201 

DATE: MAR 1 1 l~l~ 

TO: 	 Daniel R. Levinson 


Inspector General 


FROM: 	 Murilyn 1ia".enner 


AdmirtlstMtot 


SUBJECT: 	 Office of the Inspector General (OIG) Draft Report: "Questionable Billingfor 

Medicare Electrodiagnostic Tests" (OEI-04·12-00420) 

The Centers for Medicare &Medicaid Services (CMS) appreciates the opportunity to review and 

comment on the above-mentioned OIG report. In 2011, Medicare paid approximately $486 

million to 21,700 physicians for electrodiagnostic tests billed on behalf of 877,000 beneficiaries. 

Electrodiagnostic tests arc used to evaluate patients who may have nerve damage. Recent 

investigations have found that electrodiagnostic testing is an area vulnerable to fraud, waste and 

abuse. CMS issues comparative billing reports to providers for avariety of services, including 

electrodiagnostic testing. Such reports are intended to proactively educate providers and identify 

and correct errors in their billing. 

The OIG developed seven measures of questionable billing on the basis of past OIG work and 

input from CMS staff. OIG analyzed Medicare 20 II electrodiagnostic test claims to identify 

physicians who had unusually high billing for at least one of these measures. 010 also 

determined whether physicians with questionable billing received comparative billing reports in 

20 II for electrodiagnostic testing. In addition, OIG identified the geographic areas with the 

largest amounts of questionable billing. 

The OIG found that in 20 II, 4,90 I physicians had questionable billing for Medicare 

electrodiagnostic tests totaling, $139 million. OIG also found that approximately 20 percent of 

these physicians received comparative billing reports, on the basis oftheir 20 I 0 billing for 

electrodiagnostic tests. In addition, physicians in the New York, Los Angeles, and Houston 

areas had the largest total questionable billing for Medicare electrodiagnostic tests in 20 II. 

The 01G' s recommendations and CMS responses to those recommendations are discussed 

below. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 31 
 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 32 
 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 33 
 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 34 
 

 

ACKNOWLEDGMENTS 

This report was prepared under the direction of Dwayne Grant, Regional 

Inspector General for Evaluation and Inspections in the Atlanta regional 

office, and Jaime Durley, Deputy Regional Inspector General. 

Latrice Rollins served as lead analyst. Central office staff who provided 

support include Scott Horning, Althea Hosein, Kevin Manley, Christine 

Moritz, and Mandy Walz. 

Questionable Billing for Medicare Electrodiagnostic Tests (OEI-04-12-00420) 35 
Office of Inspector General

http://oig.hhs.gov 

The mission of the Office of Inspector General (OIG), as mandated by Public Law 95-452, as 

amended, is to protect the integrity of the Department of Health and Human Services 

(HHS) programs, as well as the health and welfare of beneficiaries served by those 

programs. This statutory mission is carried out through a nationwide network of audits, 

investigations, and inspections conducted by the following operating components: 

Office of Audit Services 

The Office of Audit Services (OAS) provides auditing services for HHS, either by conducting 

audits with its own audit resources or by overseeing audit work done by others. Audits 

examine the performance of HHS programs and/or its grantees and contractors in carrying 

out their respective responsibilities and are intended to provide independent assessments of 

HHS programs and operations. These assessments help reduce waste, abuse, and 

mismanagement and promote economy and efficiency throughout HHS. 

Office of Evaluation and Inspections 

The Office of Evaluation and Inspections (OEI) conducts national evaluations to provide 

HHS, Congress, and the public with timely, useful, and reliable information on significant 

issues. These evaluations focus on preventing fraud, waste, or abuse and promoting 

economy, efficiency, and effectiveness of departmental programs. To promote impact, OEI 

reports also present practical recommendations for improving program operations. 

Office of Investigations 

The Office of Investigations (OI) conducts criminal, civil, and administrative investigations 

of fraud and misconduct related to HHS programs, operations, and beneficiaries. With 

investigators working in all 50 States and the District of Columbia, OI utilizes its resources 

by actively coordinating with the Department of Justice and other Federal, State, and local 

law enforcement authorities. The investigative efforts of OI often lead to criminal 

convictions, administrative sanctions, and/or civil monetary penalties. 

Office of Counsel to the Inspector General 

The Office of Counsel to the Inspector General (OCIG) provides general legal services to 

OIG, rendering advice and opinions on HHS programs and operations and providing all 

legal support for OIG’s internal operations. OCIG represents OIG in all civil and 

administrative fraud and abuse cases involving HHS programs, including False Claims Act, 

program exclusion, and civil monetary penalty cases. In connection with these cases, OCIG 

also negotiates and monitors corporate integrity agreements. OCIG renders advisory 

opinions, issues compliance program guidance, publishes fraud alerts, and provides other 

guidance to the health care industry concerning the anti-kickback statute and other OIG 

enforcement authorities.