Department of Health and Human Services 

OFFICE OF

INSPECTOR GENERAL

 

 

QUESTIONABLE 

BILLING PATTERNS OF 

PORTABLE X-RAY SUPPLIERS 

Daniel R. Levinson 

Inspector General 

December 2011 

OEI-12-10-00190 
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 EXECUTIVE SUMMARY

OBJECTIVES

1. To identify portable x-ray suppliers with questionable billing

patterns that may be associated with inappropriate Medicare 

payments. 

2. To identify claims for portable x-ray services that may warrant 

further review. 

BACKGROUND

Medicare paid portable x-ray suppliers approximately $225 million 

under the Part B benefit in 2009 for x-rays of the extremities, pelvis, 

spine, skull, chest, and abdomen. Portable x-ray suppliers provide 

diagnostic imaging services at patients’ locations—most often 

residences, including private homes and group living facilities, such as 

nursing homes—rather than in a traditional clinical setting, such as a 

doctor’s office or hospital. Medicare pays portable suppliers separately 

for up to four components of the service: transporting the equipment to 

the beneficiary’s location, setting it up for use, administering the test, 

and interpreting the results. Eighty percent of the amount Medicare 

paid to portable suppliers in 2009 reimbursed them for transporting and 

setting up the x-ray equipment. 

Federal regulations stipulate that portable x-rays must be ordered by a 

licensed medical doctor or doctor of osteopathy who is treating the 

beneficiary for a specific medical problem and who uses the results of 

the x-ray in managing it. The order must also state the need for 

portable services.

Medicare pays for the full transportation component once for each trip 

to a particular location. For example, if a supplier furnishes chest 

x-rays to three patients at one nursing home during a single trip, 

Medicare pays one-third the full transportation component rate for each 

patient. While it pays the full rate only once per trip, Medicare pays 

that full rate again for each return trip to a facility on a particular day.

We used Medicare claims data to assess portable x-ray suppliers on 

eight characteristics we developed that describe questionable billing 

patterns: (1) portable services ordered by nonphysicians, (2) no recent 

contact between beneficiary and ordering provider, (3) same-day 

services in multiple settings, (4) billing for return trips, (5) portable 

x-rays per beneficiary, (6) beneficiary contact with multiple portable 
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EXECUTIVE SUMMARY

suppliers, (7) beneficiary use of stationary x-ray services, and 

(8) beneficiary DME utilization. We also merged these characteristics 

into a combined score for each supplier describing its overall billing 

pattern. We then identified thresholds for each characteristic and the 

combined score, which, if exceeded by a supplier, signified questionable

billing. In addition, we analyzed claims data to determine the total 

amount Medicare paid for portable services ordered by nonphysicians 

and for apparent return trips to facilities. 

FINDINGS

Twenty portable x-ray suppliers exhibited questionable billing 

patterns. We identified 20 suppliers that exceeded thresholds on at 

least 2 of the characteristics of questionable billing we developed and

exceeded the threshold for the combined score. Thirteen of these 

suppliers were located in the Miami, Florida, area. 

Medicare paid portable x-ray suppliers approximately $12.8 million 

for return trips to nursing facilities. As a typical example, one supplier 

submitted a claim for the full transportation component for each of two 

beneficiaries on a particular day (rather than one-half of the full

transportation component for two beneficiaries on a particular day) and 

each claim was paid at the full rate. However, data show that these two 

beneficiaries were located in the same nursing home on that date. 

Claims data do not provide sufficient information to determine whether 

the supplier billed correctly for two separate trips to the facility or 

whether the supplier administered tests to the two beneficiaries during 

a single trip and incorrectly claimed full reimbursement of the 

transportation component for each beneficiary.

Medicare paid at least $6.6 million for portable x-ray services that 

were ordered by nonphysicians and therefore not covered. Nurse 

practitioners ordered $4.3 million of these services, while physician 

assistants and podiatrists ordered $1 million and $900,000, respectively. 

Registered nurses, chiropractors, and other medical professionals 

accounted for the remainder. Medicare paid an additional $5.9 million 

for services for which we could not determine the credentials of the 

ordering providers. 
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EXECUTIVE SUMMARY

RECOMMENDATIONS

Portable x-rays constitute a small portion of overall Medicare payments 

for diagnostic imaging services, but the questionable claims patterns we 

found raise concerns about the integrity of payments to certain 

suppliers. Furthermore, payments for portable services ordered by 

nonphysicians clearly violate Federal regulations and should be 

recovered. Lastly, payments for return trips to facilities, while not 

necessarily inappropriate, may represent an additional opportunity for 

program savings. Therefore, we recommend that CMS: 

Take appropriate action on portable x-ray suppliers referred by the 

Office of Inspector General. 

Establish a process to periodically identify portable x-ray suppliers 

that merit greater scrutiny and follow up as appropriate.

Determine what portion of the $12.8 million it paid for return trips in 

2009 actually reimbursed suppliers for incorrectly billed 

transportation component claims and collect overpayments where 

appropriate.

Collect the $6.6 million in overpayments for portable x-ray services 

rendered in 2009 that were ordered by nonphysicians. 

Implement procedures to ensure that it pays for portable x-ray 

services only when ordered by a physician and establish 

appropriate controls. 

AGENCY COMMENTS AND OFFICE OF INSPECTOR GENERAL 

RESPONSE

CMS concurred with our recommendations. CMS stated that since the 

draft report was issued, it has embarked on a new fraud prevention 

initiative to help identify suspect fee-for-service claims, including the 

kinds of questionable billing described in this report. CMS also stated 

that it is leveraging internal data and publicly available information to 

strengthen its provider-screening process. CMS further indicated that it 

is revising the Medicare Benefit Policy Manual to be consistent with the 

regulations that would preclude Medicare from paying for portable x-ray 

services that are not ordered by a licensed medical doctor or doctor of 

osteopathy.

For the full text of CMS’s comments, see Appendix D. 
 TABLE OF CONTENTS

EXECUTIVE SUMMARY ................................ ..... i

INTRODUCTION ............................................ 1 

FINDINGS ................................................. 11

Twenty portable x-ray suppliers exhibited questionable billing 

patterns .............................................. 11

Medicare paid portable x-ray suppliers approximately 

$12.8 million for return trips to nursing facilities ............. 12

Medicare paid at least $6.6 million for portable x-ray services 

that were ordered by nonphysicians and therefore not covered . . 12

RECOMMENDATIONS .................................. 14

Agency Comments and Office of Inspector General Response . . . . 16

APPENDIXES ............................................. 18

A: Detailed Methodology for Evaluating Questionable Claims 

 Patterns ............................................ 18

 B: Distributions of Characteristics and Combined Score With 

 Related Thresholds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

C: Billing Patterns of the 20 Selected Suppliers . . . . . . . . . . . . . . 23

 D: Agency Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

ACKNOWLEDGMENTS .................................. . 28
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OBJECTIVES 

1. To identify portable x-ray suppliers with questionable billing

patterns that may be associated with inappropriate Medicare 

payments.1

2. To identify claims for portable x-ray services that may warrant 

further review. 

BACKGROUND

Medicare paid portable x-ray suppliers approximately $225 million 

under the Part B benefit for x-rays rendered in 2009. Portable x-ray 

suppliers provide diagnostic imaging services at patients’ locations—

most often residences, including private homes and group living 

facilities, such as nursing homes—rather than in a traditional clinical 

setting, such as a doctor’s office or hospital. The supplier transports 

mobile diagnostic imaging equipment to the patient’s location, sets up 

the equipment, and administers the test onsite. The supplier may 

interpret the results itself or it may provide the results to an outside 

physician for interpretation.

Only 20 percent of 2009 Medicare payments to portable x-ray suppliers, 

$44 million, was for administering the test and interpreting the results, 

services for which portable suppliers are paid the same rates as 

stationary x-ray providers. The remaining 80 percent, $181 million, 

reimbursed suppliers for transporting the equipment to the beneficiary’s 

location and setting it up for use (see Figure 1). On average, Medicare 

paid approximately $17 for administration and interpretation and $80

for transportation and setup of each portable x-ray in 2009, a 

substantial premium over the cost of the stationary service. 

Nevertheless, to the extent beneficiaries would otherwise require 

medical transportation to a stationary x-ray provider, portable x-rays 

may represent a cost savings to Medicare. If a portable x-ray patient 

had qualified for and received nonemergency ambulance transportation 

to a stationary provider instead of receiving the portable service, 

1 Payments (also known as reimbursed amounts) refer to the amount paid for a covered 

service after the deductible and coinsurance amounts have been deducted. Centers for 

Medicare & Medicaid (CMS), Glossary. Accessed at 

http://www.cms.gov/apps/glossary/search.asp?Term=payment&Language=English on 

May 16, 2011.

 INTRODUCTION
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INTRODUCTION

Medicare would have paid the same $17 to the stationary provider for 

administration and interpretation, but $119 (on average) to the 

ambulance company for transportation.2

FIGURE 1

Most payments to 

portable x-ray 

suppliers are for 

transporting the 

equipment.

Source: Office of Inspector General (OIG) analysis of 2009 Medicare National Claims History weekly carrier data, 

2011.

Administration and 

interpretation

20%

Setup of equipment

10%

Transportation of 

equipment

70%

2009 Payments to Portable X-ray Suppliers for X-rays,

by Component

Medicare coverage of portable x-ray services is governed by Federal 

laws and regulations and CMS policy. The Code of Federal Regulations 

(CFR) provides licensing, registration, staffing, and safety requirements 

for portable x-ray suppliers.3 In particular, 42 CFR § 486.106 requires

that portable x-rays be ordered by a physician, defined by that 

regulation as a licensed medical doctor (MD) or doctor of osteopathy 

(DO). The order must specify, in writing, both the reason for the x-ray 

service and the need for portable services. Portable x-rays, like all 

diagnostic tests, also “must be ordered by the physician who is treating 

the beneficiary ... and who uses the results in the management of the 

beneficiary’s specific medical problem.”4 The Medicare Benefit Policy 

Manual limits reimbursable portable x-rays to those of the extremities, 

pelvis, spine, skull, chest, and abdomen (collectively referred to 

hereafter as “covered x-rays”).5 Portable x-ray suppliers may also 

2 OIG analysis of 2009 Medicare National Claims History weekly carrier data, 2010.

3 Applicable regulations are found at 42 CFR § 486.100 through 42 CFR § 486.110.

4 42 CFR § 410.32(a).

5 CMS, Medicare Benefit Policy Manual, Pub. No. 100-02, ch. 15, § 80.4.3.
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INTRODUCTION

furnish electrocardiograms and mammograms,6 though these services 

accounted for less than 1 percent of portable suppliers’ Medicare 

payments for services rendered in 2009.7

Billing Procedures for Portable X-Ray Services

The Medicare Claims Processing Manual separates portable x-rays into 

as many as four components for billing and payment purposes.8

Portable x-ray suppliers bill the technical and professional components 

in the same manner as other diagnostic imaging providers. To bill for 

the professional or technical component, the supplier submits a billing 

code to Medicare that identifies the test along with a modifier that 

specifies which component was furnished (modifier TC for the technical 

component or modifier 26 for the professional component).

 As with 

all diagnostic imaging tests, Medicare pays separately for administering 

the portable x-ray (the technical component) and interpreting the 

results (the professional component). For portable x-rays, Medicare also 

pays separately for bringing the equipment to the beneficiary’s location 

(the transportation component) and preparing it for use (the setup 

component).

9 If the 

supplier furnishes both the technical and professional components

(referred to as a global service), it submits a code with neither 

modifier.10

The setup and transportation components pertain solely to portable

services. To bill for the setup component, the supplier submits one unit 

of billing code Q0092 for each imaging procedure furnished to the 

beneficiary (e.g., if the supplier furnishes a chest x-ray and a wrist 

x-ray, the supplier bills two units of Q0092).11

6 CMS, Medicare Benefit Policy Manual, Pub. No. 100-02, ch. 15, §§ 80.4.3 and 80.4.5.

 To bill for the 

transportation component, the supplier submits a billing code and 

modifier that, taken together, specify the number of patients to whom 

the supplier furnished a portable x-ray during a single trip to a 

particular location. If the supplier used the equipment for one patient 

during the trip, the supplier bills code R0070 for the transportation 

component. If the supplier used the equipment for more than one 

7 OIG analysis of 2009 Medicare National Claims History weekly carrier data, 2010.

8 CMS, Medicare Claims Processing Manual, Pub. No. 100-04, ch. 13, § 90.

9 CMS, Medicare Claims Processing Manual, Pub. No. 100-04, ch. 23, Addendum – 

MPFSDB Record Layouts, 2008 File Layout and 2009 File Layout, Field #5.

10 Ibid.

11 CMS, Medicare Claims Processing Manual, Pub. No. 100-04, ch.13, § 90.4.
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INTRODUCTION

patient during the trip, it bills code R0075 for each patient. The 

supplier also attaches a modifier that further specifies the total number 

of patients seen at the location during the trip (modifier UN, UP, UQ, 

UR, or US for two, three, four, five, or six or more patients, 

respectively).12

No modifier or code exists to indicate when a supplier makes a return 

trip to a particular location on a given day, which creates ambiguity in 

the claims data. For example, a supplier might bill R0070 for each of 

two beneficiaries known to be at the same location on a given day. This 

could represent the correct billing of the transportation component for 

two separate trips to that location or the miscoding of a single trip 

during which the supplier saw both beneficiaries.

Payment for Portable X-Ray Services

The Medicare Physician Fee Schedule establishes payment rates for the 

technical and professional components of diagnostic imaging services. 

Medicare pays portable x-ray suppliers the same rates for these 

components as it does other diagnostic imaging providers. The fee 

schedule also establishes the payment rate for the setup component. 

Each Medicare claims payment contractor determines the 

transportation component rate for its jurisdiction based on instructions 

in the Medicare Claims Processing Manual. 

Medicare pays each jurisdiction’s full transportation rate for R0070 and

a prorated portion of the full rate for R0075 based on the modifier 

submitted. For example, Medicare pays one-fourth the full rate for each

instance of R0075 with modifier UQ (four patients). As shown in 

Table 1, Medicare pays more for the transportation and setup 

components than it does for the professional and technical components 

of any of the three diagnostic imaging tests for which portable x-ray 

suppliers most commonly bill.13 This difference is most substantial 

when a portable x-ray supplier sees only one patient during a trip to a 

location. In that case, Medicare pays at least four times as much for the 

transportation and setup of the equipment as it does for the technical 

and professional components combined.

12 If a supplier sees more than six patients in a single trip to a location, it bills R0075 

with the US modifier for each patient, regardless of the actual number of patients seen. 

CMS, Medicare Claims Processing Manual, Pub. No. 100-04, ch.13, § 90.3.

13 The three x-ray billing codes displayed accounted for approximately 53 percent of the 

total amount that portable x-ray suppliers billed for covered x-rays in 2009.
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INTRODUCTION

TABLE 1

Payment Rates for Common Portable X-Ray Services

Service Description

Billing

Code Modifier

2009 Payment 

Rate*

Chest x-ray; single view, 

frontal 71010 Technical Component (TC) $14.79

Professional Component (26) $ 9.02

Chest x-ray; two views, 

frontal and lateral 71020 TC $20.56

26 $11.18

Hip x-ray; complete, 

minimum two views 73510 TC $25.25

26 $10.82

Setup component Q0092 - $16.23

Transportation component; 

one patient R0070 - $145.41

Transportation component; 

multiple patients R0075

UN (2 patients) $72.71

UP (3 patients) $48.47

UQ (4 patients) $36.35

UR (5 patients) $29.08

US (6 or more patients) $24.24

Source: Medicare Physician Fee Schedule, 2009, and OIG analysis of 2009 Medicare National Claims History 

Carrier Claims File, 2010. *

The payment rates displayed for the x-rays and setup components are the physician fee schedule national 

payment amounts for 2009. The payment rates displayed for the transportation component are the median 

2009 allowed amounts.

Additional Background

This study was conducted as part of the Health Care Fraud 

Prevention and Enforcement Action Team (HEAT) initiative, which 

focuses on reducing health care fraud through the use of innovative 

data analysis and enhanced cooperation between the Department of 

Justice (DOJ), Department of Health and Human Services (HHS) 

OIG, and CMS.14

METHODOLOGY

To meet our objectives, we used the Medicare National Claims History 

weekly carrier data (hereafter, Part B data); nursing home stay 

information in the Minimum Data Set (MDS); and Medicare Skilled 

Nursing Facility (SNF), Inpatient, Outpatient, Hospice, and Durable 

Medical Equipment (DME) National Claims History Standard Analytic 

14 DOJ and HHS, HEAT Task Force Success. Accessed at 

http://www.stopmedicarefraud.gov/heatsuccess/index.html on January 19, 2011. 
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INTRODUCTION

File data for services rendered in 2008 and 2009.15

To focus on suppliers that regularly billed Medicare for portable x-ray 

services, we used the following process to define our study population. 

First, we identified all 2009 Part B claims billed with specialty code 63, 

which identifies the service provider as a portable x-ray supplier. There 

were 521 such suppliers in this set of claims. Next, we identified all 

claims from these suppliers for covered x-rays by examining the billing 

codes on the claims. We then identified all claims for the transportation 

or setup components billed by the same supplier for the same 

beneficiary on the same day as a covered x-ray. Lastly, we summarized 

these transportation and setup component claims by supplier to 

determine the amount that each supplier billed for these components for 

a covered x-ray. We selected the 352 suppliers that billed at least

$1,000 for the transportation and setup components to be our 

population.

 We also used 

National Plan and Provider Enumeration System (NPPES) data, which 

link Medicare providers’ names, addresses, and other information to 

their National Provider Identifiers (NPI), to identify the suppliers and 

ordering entities reported on claims.

We used the claims data to calculate eight characteristics that represent 

questionable claims patterns for each supplier. Based on conversations 

with CMS staff and OIG investigators, prior experience in other 

payment areas, and our own professional judgment, we determined that 

these characteristics may be associated with inappropriate Medicare 

payments for portable x-rays. The characteristics generally reflected

situations that occurred rarely in the population, but, with one

exception (portable services ordered by nonphysicians), were not 

necessarily inappropriate. Analysis of these characteristics are meant 

to identify suppliers that merit greater scrutiny, not to provide 

conclusive evidence of improper payments. The eight characteristics are 

briefly described below; Appendix A provides a full description of all

characteristics and the process for selecting them.

o Portable services ordered by nonphysicians. This characteristic 

represents the percentage of each supplier’s charges for portable 

15 At the time we conducted our analysis, claims received through March 24, 2010, were 

the most recent available. These claims represent approximately 98 percent of the total 

payments made through December 2010 to portable x-ray suppliers for services rendered in 

2009.
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INTRODUCTION

services that was ordered by entities that lack MD or DO 

credentials. Federal regulations require that Medicare portable 

x-ray services be ordered by a licensed MD or a licensed DO. 

o No recent contact between beneficiary and ordering provider. This 

characteristic represents the percentage of each supplier’s charges 

that was for a service when the beneficiary had not seen the 

ordering provider within 6 weeks prior to the service. By 

regulation, all diagnostic tests must be ordered by the physician 

treating the beneficiary and the results must be used by the 

ordering physician to treat a specific medical problem.16 We expect 

that a claim for service from the ordering provider would generally 

precede the portable x-ray by a reasonably short period—we used 

6 weeks to be conservative. Additionally, prior OIG work has 

shown that apparent lack of contact between an ordering provider 

and the beneficiary may predict improper activity in other benefit 

areas. 

o Same-day services in multiple settings. This characteristic 

represents the percentage of each supplier’s portable services that 

occurred on a day on which the beneficiary also had services in a 

clinical setting (e.g., office or hospital). Pursuant to Federal 

regulations, a beneficiary must have a specific need for portable 

services documented by the ordering physician.17 Logically, if the 

beneficiary received services in a clinical setting on a particular 

day, the need for portable services is less clear than if all services 

on that day were rendered at the beneficiary’s location. We 

excluded claims for services and items for which the beneficiary is 

not normally physically present at the place of service (e.g., 

laboratory services) from this analysis. 

o Billing for return trips. This characteristic represents the percentage

of each supplier’s Medicare payments related to transportation 

component claims that appear to be billed for a trip to a facility 

already visited that day. While a supplier may legitimately make 

multiple trips to a facility, it is also financially advantageous for the 

supplier to see all beneficiaries at a location in a single trip, but bill 

as if it made a separate trip for each. Additionally, a supplier that 

16 42 CFR § 410.32.

17 42 CFR § 486.106.
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INTRODUCTION

submitted fictitious claims using fraudulently acquired beneficiary 

numbers might be unaware that the beneficiaries were collocated. 

o Portable x-rays per beneficiary. This characteristic represents the 

average number of covered x-rays each supplier billed for its 

beneficiaries in 2009. Suppliers that submit an unusually large 

number of x-rays compared to the number submitted by their peers 

could be billing for medically unnecessary tests or services not 

rendered. 

o Beneficiary contact with multiple portable suppliers. This 

characteristic represents the percentage of each supplier’s 

beneficiaries who also appeared on claims from another portable 

x-ray supplier in 2009. Preliminary data analysis showed that few 

beneficiaries received portable services from more than one 

supplier. Therefore, a large percentage with this characteristic may 

signify inappropriate patient sharing. 

o Beneficiary use of stationary x-ray services. This characteristic 

represents the percentage of beneficiaries who received frequent 

x-rays from both portable x-ray suppliers and stationary providers 

in 2009. First, we identified the 10 covered x-ray codes most 

frequently billed by portable x-ray suppliers as a whole. These 10 

services accounted for 75 percent of the total allowed charges for 

x-rays from suppliers in our population in 2009. We then 

determined the percentage of each portable x-ray supplier’s 

beneficiaries for whom both the supplier and a stationary x-ray 

provider submitted a claim for any of these services. If a large 

percentage of a portable supplier’s beneficiaries also get stationary 

services, it may indicate that the supplier is billing for medically 

unnecessary services or services not rendered. 

o Beneficiary DME utilization. This characteristic represents the 

average amount billed in 2009 for any DME item by any entity for 

each beneficiary of a portable x-ray supplier. DME is a frequently 

abused benefit, and if a supplier’s beneficiaries receive unusually 

large amounts of DME compared to those of other suppliers, it could

indicate that the supplier is billing using compromised beneficiary 

numbers. 

We used these eight characteristics to evaluate suppliers’ billing 

patterns. First, we analyzed the distribution of each characteristic to 

establish thresholds that signify questionable billing. Next, we 

determined the number of characteristics on which each supplier 
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INTRODUCTION

surpassed the related threshold. Then we combined the eight 

characteristics to create a score for each supplier that we used to 

compare suppliers’ overall patterns of questionable billing (referred to 

hereinafter as the combined score). We analyzed the distribution of the 

combined score to establish a “questionable” threshold in the same 

manner as for the individual characteristics. Finally, to focus on the 

suppliers most likely to be associated with inappropriate payments, we

set criteria to identify suppliers that exhibited questionable billing 

patterns. To be selected, a supplier had to exceed thresholds for at least 

two individual characteristics and the threshold on the combined score. 

In addition to evaluating the supplier-level characteristics, we 

conducted two related analyses of claims for portable x-ray services as 

a whole to identify individual claims that may warrant further 

review. First, we matched the Part B data to the NPPES data to 

determine the credentials of the ordering provider on each claim and 

then calculated the amount Medicare paid for services ordered by 

nonphysicians. The methodology for this analysis was identical to 

that for the characteristic “Portable services ordered by 

nonphysicians,” except that we applied it to the entire set of claims 

billed by suppliers in our population.

Second, we applied the methodology we used for the characteristic 

“Billing for return trips” to claims from our entire population to 

determine the total amount Medicare paid portable x-ray suppliers for 

return trips. That is, we matched the Part B and MDS data to 

identify the nursing facility, if any, where each beneficiary was 

located on the day of the service.18 We then determined the number 

of trips the supplier appeared to have made to each facility each day 

based on the codes and modifiers used to bill for the transportation 

component for beneficiaries located at that facility. For example, if a 

supplier billed R0070 for two patients located in the same facility, we 

determined the supplier made two trips to that facility. Then we 

calculated the total amount Medicare paid for return trips to a 

facility. 

18 If the portable x-ray service fell on the first or last day of a nursing facility stay, we 

considered the beneficiary to not be in a nursing facility that day.
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INTRODUCTION

Limitations

We did not independently verify the accuracy of the data we used for 

this study; therefore, the accuracy of our findings is limited by the 

accuracy of the data. With the exception of portable services ordered by 

nonphysicians, none of the characteristics we analyzed necessarily 

implies that a particular claim is inappropriate or that a particular 

supplier submitted inappropriate claims. We designed this study to 

identify suppliers that merit greater scrutiny, not to provide conclusive

evidence of improper payments. 

A portion of our analysis focuses on the ordering NPIs reported on 

claims submitted by portable x-ray suppliers. In an October 15, 2008, 

program transmittal, CMS instructed suppliers to use their own NPIs 

as the ordering NPIs on Medicare claims if they cannot determine the

NPIs of the ordering providers.19 Therefore, we cannot determine 

whether claims that report the suppliers’ own NPIs in the ordering NPI 

field represent services ordered by nonphysicians. Instead, we 

specifically report on the incidence of suppliers’ using their own NPIs in 

the ordering field in the findings. According to a CMS Transmittal, 

Medicare contractors were to stop paying claims that lack a valid NPI 

for the ordering provider on July 5, 2011.20

Standards

 The transmittal also 

indicated that the date was subject to change. CMS recently stated that 

it anticipates implementing edits in early 2012 to stop payment for 

claims that lack a valid NPI. 

This study was conducted in accordance with the Quality Standards for 

Inspection and Evaluation approved by the Council of the Inspectors 

General on Integrity and Efficiency.

19 CMS, Transmittal 270, Change Request 6093, October 15, 2008.

20 CMS, Transmittal 825, Change Request 6417, December 16, 2010.
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Twenty portable x-ray suppliers exhibited 

questionable billing patterns

 FINDINGS

Most suppliers rarely billed for the 

unusual situations described by the 

characteristics in our methodology, 

but 20 of the 352 in our population (5.7 percent) met our criteria for

identifying questionable billing patterns. That is, 20 suppliers exceeded 

thresholds for questionable billing on at least 2 individual 

characteristics and the threshold on the combined score, which

describes suppliers’ overall billing patterns. As shown in Table 2, 12 of 

the 20 suppliers exceeded thresholds on 4 or 

more characteristics. The characteristics on 

which the 20 suppliers most often exceeded 

thresholds were those that measured 

beneficiary use of stationary x-ray services 

(16 suppliers exceeded this threshold), 

same-day services in multiple settings 

(16 suppliers), beneficiary contact with 

multiple portable suppliers (15 suppliers), 

and beneficiary DME utilization 

(13 suppliers). Collectively, Medicare paid 

the selected suppliers approximately 

$5.2 million for portable services rendered 

in 2009. Appendix B provides for more information on how the supplier 

population performed on each characteristic. Appendix C displays

detailed information about each of the 20 suppliers that met our criteria 

for questionable billing.

The supplier with the most questionable billing pattern had the highest 

combined score and exceeded thresholds on six individual 

characteristics. Furthermore, the supplier ranked in the top 10 on the 

following 4 characteristics:

Table 2 :

Count of Suppliers That 

Exceeded Exact Number 

of Thresholds for 

Individual Characteristics

Number of 

Thresholds

Supplier 

Count

2 5

3 3

4 4 

5 7 

6 1 

Source: OIG analysis of 2008 and 

2009 Medicare and NPPES data, 

2011.

• Services ordered by nonphysicians accounted for 30 percent of 

the charges for portable services this supplier submitted, 

compared to the median value of 1.1 percent for suppliers in the

population.

• The supplier billed 53 percent of its portable services on a day 

when the beneficiary had a service in a clinical setting (median 

value 6 percent). 

• In addition, 55 percent of the supplier’s patients got services

from at least one other portable x-ray supplier (median value 

9.9 percent).
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 12

FINDINGS

• The supplier’s patients had an average of $7,970 billed on their 

behalf for DME in 2009 (median value $3,198). 

As a group, the 20 suppliers who met our criteria had several additional 

features that differentiated them from suppliers with more typical 

billing patterns. First, only 9 percent of the payments to selected 

suppliers were associated with services billed for beneficiaries in a 

nursing facility at the time of service, compared to 73 percent of the 

payments to other suppliers. Second, 13 of the selected suppliers were 

located in the Miami, Florida, area, more than half the total 

25 suppliers in our population with addresses there. All 13 Miami

suppliers surpassed thresholds on at least 3 characteristics, compared 

to only 2 of the 7 suppliers from outside the Miami area that met our 

criteria. 

Medicare paid portable x-ray suppliers 

approximately $12.8 million for return trips to

nursing facilities

Medicare paid suppliers

approximately $108 million for 

transportation component claims 

for portable x-rays furnished in 

2009 while the beneficiary was in a nursing home or SNFs, according to 

MDS data. Approximately 12 percent of this amount, $12.8 million, was 

for trips to a location apparently already visited on the same day. As a 

typical example, one supplier submitted two separate claims for 

transportation costs (R0070), one for each of two beneficiaries, on a 

particular day. Medicare paid each claim at the full transportation 

component rate. However, MDS data show that these two beneficiaries 

were located in the same nursing home on that date. Claims data do 

not provide sufficient information to determine whether the supplier 

billed correctly for two separate trips to the facility or administered 

tests to the two beneficiaries during a single trip and failed to use the 

appropriate prorated billing code. 

Medicare paid at least $6.6 million for portable 

x-ray services that were ordered by 

nonphysicians and therefore not covered

Contrary to 42 CFR § 486.106, 

which requires that portable 

x-rays be ordered by an MD or 

DO, Medicare paid $6.6 million 

for portable x-ray services ordered by nonphysicians in 2009. Nurse 

practitioners ordered services that accounted for $4.3 million of this 

amount. Physician assistants and podiatrists ordered approximately 

$1 million and $900,000, respectively. Various other medical 
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 13

FINDINGS

professionals, such as registered nurses and chiropractors, accounted for 

the remaining $400,000. 

Medicare paid an additional $5.9 million for services for which we could 

not determine whether the ordering provider possessed appropriate 

credentials. The ordering NPIs on claims that generated $1.2 million of 

this amount did not match a current record in the NPPES data or 

identified a group practice, not an individual practitioner. Additionally, 

about $4.6 million of the $5.9 million for services went to suppliers that

reported their NPIs as the ordering NPIs on the claims.21 This amount 

included $3.1 million that went to one supplier that reported its own 

NPI on nearly 100 percent of its portable x-ray claims and $842,000 for

three suppliers that used their own NPIs on claims that accounted for at 

least 20 percent of their Medicare payments. 

21 Because of rounding, the sum of the paid amounts shown for the subcategories does

not equal the total paid amount shown for services for which we could not determine 

whether the ordering providers possessed appropriate credentials.
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 14

 RECOMMENDATIONS

Portable x-rays constitute a small portion of overall Medicare payments 

for diagnostic imaging services, but the questionable claims patterns we 

found raise concerns about the integrity of payments to certain portable 

x-ray suppliers. Furthermore, payments for portable services ordered 

by nonphysicians clearly violate Federal regulations and should be 

recovered. Lastly, payments for return trips to facilities, while not 

necessarily inappropriate, may represent an additional opportunity for 

program savings. Therefore, we recommend that CMS:

Take appropriate action on portable x-ray suppliers referred by the Office of 

Inspector General

OIG is currently determining what, if any, OIG enforcement action it 

should take on the 20 suppliers we identified with questionable billing 

patterns and the 4 suppliers that derived more than 20 percent of their 

Medicare payments from claims on which the suppliers reported their 

own NPIs as the ordering NPIs. After we complete our internal process, 

we will provide CMS (under separate cover) the identities of those 

suppliers against which we believe it would be appropriate for CMS to 

take administrative action.

Establish a process to periodically identify portable x-ray suppliers that 

merit greater scrutiny and follow up as appropriate 

Although our methodology cannot positively identify suppliers that have 

received inappropriate Medicare payments, we identified some suppliers 

with questionable claims patterns that merit greater scrutiny. CMS 

should establish a process to identify portable x-ray suppliers that 

present a likely risk to the program and refer them for appropriate 

administrative or enforcement action. We leave the details of such a 

process to CMS’s discretion, but as CMS has access to all the data 

sources we used for our analysis, it could use the methodology in this 

report as a guide. Given the preponderance of Miami suppliers among 

those we identified with questionable billing, CMS may initially wish to 

focus on Miami and later expand to other high-risk jurisdictions. 

Determine what portion of the $12.8 million it paid for return trips in 

2009 actually reimbursed suppliers for incorrectly billed transportation 

component claims and collect overpayments where appropriate

Medicare paid portable x-ray suppliers $12.8 million for apparent 

return trips to nursing facilities in 2009, but some portion of this 

amount may be attributable to incorrectly billed transportation 

component claims. That is, the supplier may have obtained excess 

reimbursement by billing as if it made multiple trips to a facility when, 
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 15

RECOMMENDATIONS

in fact, it saw all beneficiaries located in that facility in a single trip. 

CMS should instruct its contractors to conduct a focused medical review 

on a sample of these claims to identify any overpayments and determine 

the extent of errors of this type. Depending on the results of this 

preliminary review, CMS may wish to initiate more extensive reviews of 

such claims on a regular basis. CMS should also recover any 

overpayments discovered in the preliminary or more extensive review 

(if conducted).

Collect the $6.6 million in overpayments for portable x-ray services rendered 

in 2009 that were ordered by nonphysicians 

Federal regulations at 42 CFR §§ 410.32(a) and 486.106 clearly state 

that portable x-ray services must be ordered by an MD or a DO to be 

eligible for Medicare reimbursement. Therefore, CMS should instruct 

its contractors to collect overpayments on the $6.6 million paid for 

portable x-ray services ordered by nonphysicians. Under separate 

cover, we will provide CMS the information needed to identify these 

claims. 

Implement procedures to ensure that it pays for portable x-ray services only 

when ordered by a physician and establish appropriate controls

CMS should weigh the costs and benefits of prepayment and 

postpayment controls to ensure that portable x-ray services meet the 

requirement established in 42 CFR §§ 410.32(a) and 486.106 concerning 

the credentials of the ordering provider. Depending on the results of the 

analysis, CMS could instruct its contractors to verify that the ordering 

NPI on each claim for portable x-ray services identifies an MD or a DO

before paying the claim. Alternatively, CMS could instruct its 

contractors to periodically review paid portable x-ray claims to verify 

the credentials of the ordering providers and collect overpayments 

where appropriate. CMS may explore other options at its discretion.

As part of its response to this recommendation, CMS should fully 

implement the requirement, though not specific to portable x-ray 

services, that claims for services requiring the supplier to report an 

ordering provider bear the correct NPI of that ordering provider. This 

action should eliminate payments for services for which the credentials 
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 16

RECOMMENDATIONS

of the ordering entity cannot be determined (for which CMS paid $5.9 

million in 2009). OIG made a similar recommendation in a February 

2009 report.22

AGENCY COMMENTS AND OFFICE OF INSPECTOR GENERAL 

RESPONSE

 

CMS concurred with our recommendations. CMS stated that since the 

draft report was issued, it has embarked on a new Fraud Prevention 

System to help identify suspect fee-for-service claims, including the kinds 

of questionable billing described in this report. CMS also stated that it is 

leveraging internal data and publicly available information to strengthen 

its provider-screening process which will help keep portable x-ray 

providers that have exhibited suspicious or fraudulent behaviors from 

reenrolling in Medicare. CMS further indicated that it is revising the 

Medicare Benefit Policy Manual to be consistent with the regulations that 

would preclude Medicare from paying for portable x-ray services that are 

not ordered by an MD or a DO.

Specifically, in response to our first recommendation, CMS concurred and 

stated that after it receives and reviews the necessary information about 

the suppliers and claims discussed in this report, it will take the 

appropriate administrative action.

In response to our second recommendation, CMS concurred and stated 

that it implemented a new Fraud Prevention System to detect potential 

fraud and abuse by suppliers of portable x-ray services. CMS also stated 

that it will perform periodic analyses on suppliers and will explore 

opportunities to build reliable models that can detect and generate alerts 

for suspicious activity.

In response to our third recommendation, CMS concurred but stated that 

because of limited resources and timing, it cannot initiate a review of a 

sample of portable x-ray claims at this time. Instead, CMS stated that it 

would forward the list of questionable claims to the appropriate 

contractor for further consideration. 

In response to our fourth recommendation, CMS concurred and stated 

that it plans to recover the $6.6 million in overpayments identified.

22 OIG, Medicare Payments in 2007 for Medical Equipment and Supply Claims With 

Invalid or Inactive Referring Physician Identifiers, OEI-04-08-00470.
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 17

In response to our fifth recommendation, CMS concurred and stated it is 

revising the Medicare Benefit Policy Manual to be consistent with the 

regulations that would preclude Medicare from paying portable x-rays 

that are not ordered by an MD or a DO. 

For the full text of CMS’s comments, see Appendix D.
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 18

 APPENDIX ~ A

Detailed Methodology for Evaluating Questionable Claims Patterns

Our first step in evaluating the billing patterns of portable x-ray 

suppliers was to identify potential indicators of inappropriate payments. 

Based on conversations with Centers for Medicare & Medicaid Services

staff and Office of Inspector General investigators, prior experience in 

other payment areas, and our own professional judgment, we developed 

an initial set of 16 indicators that could potentially meet this goal. 

These indicators were based either on characteristics of individual 

claims (e.g., the percentage of portable services ordered by 

nonphysicians) or on the claims histories of beneficiaries (e.g., the 

average number of portable imaging services per beneficiary).

After identifying the initial set of potential indicators, we then 

calculated each indicator for each supplier and examined the 

distribution of values across suppliers. If a distribution showed that

most suppliers had relatively low values for an indicator, but a small 

number had distinctly higher values, we determined that, for this 

indicator, a supplier’s deviation from the population was likely to be 

meaningful. Eight indicators met this criterion; these became the eight 

characteristics we chose to represent questionable billing patterns of 

suppliers. The specific methodologies we used to calculate each of the 

eight characteristics are described below.

o Portable services ordered by nonphysicians. We first matched the 

ordering National Provider Identifier (NPI) on each claim to 

National Plan and Provider Enumeration System (NPPES) data to 

identify the ordering provider. We then used two data elements 

from the NPPES—the primary taxonomy code (a self-selected code 

that captures the provider’s primary area of expertise) and the 

credentials—to determine whether the entity was a licensed 

physician. If the entity’s primary taxonomy code corresponded to a 

physician specialty or the entity listed medical doctor (MD) or doctor 

of osteopathy (DO) credentials, we considered the ordering provider

to be a physician. Failing that, if the primary taxonomy code 

indicated that the ordering provider was a group practice, the 

ordering NPI did not match a record in the NPPES or was missing, 

or the supplier reported its own NPI in the ordering field, we 

considered the credentials of the entity to be unknowable. 

Otherwise, we considered the ordering provider to be a 

nonphysician. We verified that a random sample of 10 nonphysician 

ordering entities identified through this process did not hold MD or 

DO credentials by searching State medical licensure Web sites by 
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 19

APPENDIX ~ A

the name and State of the entity. We then calculated the percentage

of each supplier’s submitted charges that were derived from claims 

ordered by nonphysicians. We limited this analysis to claims for 

services rendered on the same day and for the same beneficiary as a 

claim for the transportation or setup component to ensure that we 

included only services subject to 42 CFR § 486.106, which requires 

that portable services be ordered by a physician. 

o No recent contact between beneficiary and ordering provider. We first 

excluded claims on which the suppliers reported their own NPIs as 

the ordering NPI. We then identified each unique combination of

beneficiary, ordering provider, and service date among claims 

submitted by portable x-ray suppliers in our population. We then 

determined whether the ordering NPI appeared as the performing, 

attending, operating, or other NPI on a claim for Part B, Skilled 

Nursing Facility (SNF), Inpatient, Outpatient, or Hospice claim with 

a service date 6 weeks or less prior to the portable x-ray service. If 

so, we determined that the beneficiary and ordering provider had 

had recent contact. Otherwise, we determined that the two did not 

have recent contact. We then calculated the percentage of each 

supplier’s charges submitted for claims with no evidence of recent 

contact between the beneficiary and ordering provider. 

o Same-day services in multiple settings. We first created a dataset 

with 2009 Part B claims for all beneficiaries in our population. We 

excluded claims for transportation services, tangible goods (e.g., 

parenteral nutrition supplies), pathology and laboratory services, 

the professional component of diagnostic services, and other services 

and items for which the beneficiary is not normally present at the 

place of service. We then examined the place of service code on the 

claim to identify the setting in which the service was rendered. If 

the place of service code corresponded to a physician’s office, 

hospital, or medical clinic, we considered the setting to be clinical. If 

the code corresponded to a homeless shelter, private home, nursing 

facility, hospice, or a residential treatment facility, we considered 

the setting to be residential. If the beneficiary had a portable x-ray 

service in a residential setting on the same day as another service in 

a clinical setting, we determined that the beneficiary had services in 

multiple settings that day. We then calculated the percentage of 

each supplier’s beneficiary-service day combinations for which the 

beneficiary had services in multiple settings. 
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 20

APPENDIX ~ A

o Billing for return trips. We matched our portable x-ray claims 

population to the Minimum Data Set and SNF stay data by 

beneficiary number and date to identify the facility, if any, where 

the beneficiary was located on the day of each transportation 

component service. If the transportation component service fell on 

the first or last day of a nursing facility stay, we considered the 

beneficiary to not be in a facility. Otherwise, we considered the 

beneficiary to be in the facility identified in the stay data. We then 

grouped the transportation component claims that each supplier 

submitted for beneficiaries in each facility into trips according to the 

billing code on the claim. For instance, if a supplier submitted two 

claims with the two-patient transportation component code and one 

with the one-patient code for three beneficiaries located in the same 

facility on a certain day, we would group these claims into two trips. 

We then assigned an order to the trips according to the amount 

Medicare paid for each, with the trip for which Medicare paid the 

most as the “first” trip. Lastly, we determined the percentage of 

each supplier’s total Medicare payments derived from transportation 

component claims for any trip beyond the first to a facility. 

o Portable x-rays per beneficiary. We calculated the total number of 

covered x-rays billed by each portable x-ray supplier in 2009, 

excluding any tests for which the supplier billed only the 

professional component. We then divided this total by the number 

of beneficiaries for whom each supplier submitted a claim to get the 

average number of portable x-rays per beneficiary for each supplier. 

o Beneficiary contact with multiple portable suppliers. We counted the 

number of distinct portable x-ray suppliers that submitted a claim 

for each beneficiary in our population dataset. We then determined 

the percentage of each supplier’s beneficiaries that had claims from 

at least two portable suppliers in 2009. 

o Beneficiary use of stationary x-ray services. First, we identified the 

10 billing codes for covered x-rays most commonly billed by portable 

x-ray suppliers in our population, weighted by allowed charges. 

These 10 codes constituted approximately 75 percent of the total

allowed charges for x-rays in our population. We then created a 

dataset containing all Part B claims for these codes for beneficiaries 

in our population, regardless of the specialty of the performing 

provider. Finally, we calculated the percentage of each portable 
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 21

APPENDIX ~ A

supplier’s beneficiaries who also appeared on a claim for one of the 

codes from a stationary provider during 2009. 

o Beneficiary Durable Medical Equipment (DME) utilization. From the 

2009 DME claims data, we calculated the amount billed for any 

DME item on behalf of each beneficiary in our population. We then 

calculated the average amount of billed charges for DME per 

beneficiary who had at least one DME claim for each supplier in our 

population. 

After selecting the characteristics to use for our supplier profiles, we 

calculated thresholds for each characteristic to define questionable

billing. If the distribution of the characteristic was exponential, we set 

the threshold at the 90th percentile of the characteristic. Otherwise, we 

set the threshold at a value where, after removing suppliers above the 

threshold, the remaining values formed an approximately normal 

distribution.

We then combined the eight characteristics into an overall score, which

we called the combined score. We first determined the maximum value 

for each characteristic among the suppliers in our population. We then 

divided each supplier’s value for each characteristic by the maximum 

value for that characteristic to create a normalized score on a zero to 

one scale for each characteristic. We then summed the normalized 

values for each characteristic to create the combined score. We 

determined the threshold for the combined score in the same manner as 

for the individual characteristics. Appendix B shows the median and 

maximum values for each characteristic and the combined score as well 

as the corresponding thresholds and the number of suppliers that 

exceeded each threshold.

For example, the top supplier in our population had a value of 5.125 for 

the characteristic “Portable x-rays per beneficiary.” Therefore, we 

divided each supplier’s value for that characteristic by 5.125 to get each 

supplier’s normalized score. The top supplier had a normalized score of 

5.125 divided by 5.125, or 1. Meanwhile, the supplier with the 

minimum value on that characteristic, 0.4444, had a normalized score of 

0.4444 divided by 5.125, which is 0.0867. We performed this operation 

for each characteristic and then summed the normalized scores into the 

single combined score for each supplier.
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 22

 APPENDIX ~ B

Distributions of Characteristics and Combined Score With Related 

Thresholds

Characteristic Detail

Median 

Supplier 

Value

Maximum 

Supplier 

Value Threshold

Suppliers 

Exceeding 

Threshold

Portable services 

ordered by 

nonphysicians

Amount billed for claims 

with characteristic as 

percentage of total 

charges for portable 

services per supplier

1.09% 95.6% 14.1% 35

No recent contact 

between beneficiary 

and ordering provider

Amount billed for claims 

with characteristic as 

percentage of total 

charges per supplier

30.7% 100% 55.0% 27 

Same-day services in 

multiple settings

Service days with 

characteristic as 

percentage of total 

service days per supplier

6.04% 80.7% 11.78% 35

Billing for return trips Transportation 

component payments 

associated with return 

trips as percentage of 

total payments per 

supplier

4.55% 35.4% 11.4% 35

Portable x-rays per 

beneficiary

Mean number of 

portable x-rays per 

beneficiary per supplier

2.11 5.13 3.00 10 

Beneficiary contact 

with multiple portable 

suppliers

Percentage of each 

supplier’s beneficiaries 

that received services 

from at least one 

additional portable x-ray 

supplier

9.88% 100% 30.7% 35

Beneficiary use of 

stationary x-ray 

services

Percentage of each 

supplier’s beneficiaries 

that also received similar 

services from a 

stationary x-ray provider

11.1% 90.0% 20.8% 40

Beneficiary durable 

medical equipment 

(DME) utilization

Mean charges for DME

per beneficiary per 

supplier

$3,198 $8,732 $5,200 32

Combined score - 1.66 3.73 2.37 22 

Source: Office of Inspector General analysis of 2008 and 2009 Medicare and National Plan and Provider 

Enumeration System data, 2011. 

 
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 23

 APPENDIX ~ C

Billing Patterns of the 20 Selected Suppliers

Supplier

Characteristic

Combined 

score

(Threshold 

=2.37)

Medicare 

payments 

for portable 

x-rays 

rendered in 

Location 2009

Portable 

services 

ordered by 

nonphysicians

No recent 

contact 

between 

beneficiary 

and ordering 

provider

Same-day 

services in 

multiple 

settings

Billing for 

return trips

Portable xrays per 

beneficiary

Beneficiary 

contact with 

multiple 

portable 

suppliers

Beneficiary 

use of 

stationary 

x-ray services

Beneficiary 

DME 

utilization

A Miami X X X - - X X X 3.73 $255,749

B Miami - X X - - X X X 3.28 $482,711

C Miami - X X - - X X X 3.40 $407,910

D Miami - X X - - X X X 3.16 $335,339

E Miami - X X - - X X X 3.07 $136,788

F Miami - X X - X X X - 2.97 $176,238

G Miami X - X - - X X X 3.62 $23,201

H Other - X - - X X X X 3.69 $3,955

I Miami - - X - - X X X 2.66 $592,970

J Miami - - X - - X X X 2.90 $407,114

K Miami - - X - - X X X 2.84 $224,860

L Other X X X - - - - X 3.30 $42,025

M Miami - - X - - X X - 2.39 $236,617

N Miami - - X - - X X - 2.62 $53,462

O Miami - - - - - X X X 2.61 $833,541

P Other - - X X - - - - 2.44 $519,355

Q Other - - X - - - X - 2.41 $226,036

R Other - - X - - - - X 2.37 $145,410

S Other - - - X X - - - 3.06 $85,456

T Other - - - - - X X - 2.56 $2,428

Total 3 8 16 2 3 15 16 13 - $5.2 million

Source: Office of Inspector General analysis of 2008 and 2009 Medicare and National Plan and Provider Enumeration System data, 2011.

 
A P PEN D x D 


Agency Comments 

("....'~ DEPAR1MENT OF HEALTH & HUMAN SERVICES Centers for Medicare & Medicaid Services 

\~:5~ Administrator 

Washington. DC 20201 

DATE: AUG 0 4 2Dll 

TO: Daniel R. Levinson 

Inspector General 

FROM: Donald M. Berwick, M.D. 

Administrator 

SUBJECT: Office of Inspector General (OIG) Draft Report: "Questionable Billing Patterns 

of Portable X-Ray Suppliers" (OEI-12-10-00190) 

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

comment on the OIG draft report entitled "Questionable Billing Patterns ofPortable X-Ray 

Suppliers," (OEI-12-10-00190). The purpose ofthis report is two-fold. First, it seeks to identify 

portable x-ray suppliers with questionable billing patterns that may be associated with 

inappropriate Medicare payments. Secondly, it seeks to identify claims for portable x-ray 

services that may warrant further review. 

Portable x-ray suppliers provide diagnostic imaging services at patients' locations such as private 

homes and group living facilities, rather than in a traditional clinical setting, such as a doctor's 

office or hospital. As stated in the report portable x-rays constitute eight percent of the amount 

Medicare paid to portable suppliers in 2009 reimbursed them for transporting and setting up the 

equipment. According to the OIO's report, Medicare paid approximately $225 million under the 

Part B benefit in 2009 for x-rays of the extremities, pelvis, spine, skull, chest, and abdomen. 

However, we recognize that such questionable billing patterns raise legitimate concerns about 

potentially inappropriate Medicare payments and appreciate the OIG bringing this issue to our 

attention. Since the report was issued, CMS has embarked on a new fraud prevention initiative 

which will help eMS identify suspect fee-for-service claims, including the kinds ofquestionable 

billing described in this report. 

Launched on June 30, 2011, the eMS's new Fraud Prevention System (FPS) reviews every feefor-service claim, including those submitted by portable x-ray suppliers, to identify claims and 

providers that merit greater scrutiny. The new system alerts eMS to unusual billing patterns and 

other suspicious behavior while simultaneously prioritizing claims so eMS can strategically 

target resources for additional review, investigation, and administrative action as necessary. 

eMS is now able to review claims, investigate providers, make referrals to law enforcement, and 

take administrative actions against providers more efficiently than before. eMS will perform 

analyses on portable x-ray suppliers and will explore opportunities to build reliable models that 

can detect and generate alerts for suspicious portable x-ray activity. 

OEI·12·10·00190 QUESTIONABLE BILLING PATTERNS OF PORTABLE X·RAY SUPPLIERS 24 
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 25

APPENDIX ~ D
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 26

APPENDIX ~ D
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 27

APPENDIX ~ D
OEI - 1 2 - 1 0 - 00190 QUESTIONABLE B ILLING PATTERNS OF P ORTABLE X - RAY S UPPLIERS 28

 ACKNOWLEDGMENTS

This report was prepared under the direction of Dave Graf, Director, 

Technical Support Staff, in the Baltimore office. 

Scott Hutchison served as the team leader for this study. Other 

principal Office of Evaluation and Inspections staff who contributed to 

the report include Berivan Demir Neubert, Rita Wurm, Scott Horning, 

and Robert Gibbons.
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.