Department of Health and Human Services 

OFFICE OF 

INSPECTOR GENERAL 

P A UBLIC SSISTANCE 

REPORTING INFORMATION 

SYSTEM: S TATE 

PARTICIPATION IN THE 

MEDICAID INTERSTATE 

MATCH IS LIMITED 

Brian P. Ritchie 

Acting Deputy Inspector General for 

Evaluation and Inspections 

July 2014 

OEI-09-11-00780 
 

EXECUTIVE SUMMARY – PUBLIC ASSISTANCE REPORTING INFORMATION 

SYSTEM: STATE PARTICIPATION IN THE MEDICAID INTERSTATE MATCH 

IS LIMITED, OEI-09-11-00780 

WHY WE DID THIS STUDY 

In 2013, eligibility errors caused an estimated 57 percent of improper Medicaid payments, 

representing approximately $8.2 billion in Federal expenditures. One type of eligibility 

error occurs when beneficiaries remain enrolled in a State’s Medicaid program for which 

they are ineligible because they are no longer residents of the State and/or have failed to 

timely report a change in circumstances (i.e., address and residency) to the State. The 

Public Assistance Information Reporting System (PARIS) Medicaid Interstate Match is an 

important tool that has the potential to reduce improper Medicaid payments by identifying 

beneficiaries who are enrolled in multiple State Medicaid programs. Although the Social 

Security Act (SSA) mandates that States participate in the match, neither the SSA nor 

guidance from the Centers for Medicare & Medicaid Services (CMS) defines the meaning 

of such participation. 

HOW WE DID THIS STUDY 

We discuss “participation” in the Medicaid Interstate Match as four steps that States 

perform to reduce improper payments: (1) submitting Medicaid enrollment data, 

(2) verifying matches, (3) discontinuing Medicaid benefits for ineligible beneficiaries, and 

(4) recovering any improper Medicaid payments. To determine the extent to which States 

participate in the match, we gathered information from States for a random sample of 

300 matches from the August 2011 match. We conducted structured interviews with 

officials from CMS to determine the extent to which they provided guidance to States on 

the four steps. Finally, we conducted a survey of State Medicaid agencies and collected 

their match policies to determine the extent to which States have policies on the four steps. 

WHAT WE FOUND 

States’ participation in the Medicaid Interstate Match is limited. CMS guidance to States 

for participating in the match is limited, and States reported that they needed more 

guidance. Most States had policies addressing at least one of the steps for participating in 

the match. 

WHAT WE RECOMMEND 

We recommend that CMS issue guidance to States on the requirement for participating in 

the Medicaid Interstate Match. CMS concurred with our recommendation. 

 
 

 

TABLE OF CONTENTS 

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

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

Methodology................................................................................................5 

Findings........................................................................................................9 

States’ participation in the Medicaid Interstate Match is limited.....9 

CMS guidance to States for participating in the Medicaid 

Interstate Match is limited; States reported that they needed 

more guidance................................................................................11
 

Most States had policies addressing at least one of the steps 

for participating in the Medicaid Interstate Match ........................12 

Conclusion and Recommendation .............................................................14 

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

Appendixes ................................................................................................17 

Appendix A: Confidence Intervals................................................17 

Appendix B: Number of Projected Matches for the 

August 2011 Medicaid Interstate Match ........................................18 

Appendix C: Agency Comments ..................................................19 

Acknowledgments......................................................................................21 
 

 

 

 

OBJECTIVES 

To determine the extent to which: 

1.	 States participate in the Public Assistance Reporting Information 

System (PARIS) Medicaid Interstate Match, 

2.	 the Centers for Medicare & Medicaid Services (CMS) provides 

guidance to States for participating in the PARIS Medicaid Interstate 

Match, and 

3.	 States have policies and procedures for participating in the PARIS 

Medicaid Interstate Match. 

BACKGROUND 

CMS estimates that nationally, 5.8 percent of Medicaid payments made in 

fiscal year 2013 were improper, representing $14.4 billion in Federal 

expenditures.1 Eligibility errors caused an estimated 57 percent of these 

improper payments,2 representing approximately $8.2 billion in Federal 

expenditures.3 One type of eligibility error occurs when beneficiaries 

remain enrolled in a State’s Medicaid program for which they are ineligible 

because they are no longer residents of the State and/or have failed to 

timely report a change in circumstances (i.e., address and residency) to the 

State. Therefore, procedures to capture and share State residency changes 

are essential for reducing improper payments resulting from beneficiary 

enrollment in multiple State Medicaid programs.4 PARIS is an important 

tool that has the potential to reduce improper Medicaid payments by 

identifying beneficiaries who are enrolled in multiple State Medicaid 

programs. 

PARIS 

PARIS provides all 50 States, the District of Columbia, and Puerto Rico5 

(States) with information to aid them in detecting and preventing improper 

payments in the administration of public assistance and medical assistance 

1

 Department of Health and Human Services (HHS), Fiscal Year 2013 Agency Financial 

Report, December 16, 2013, p. 173. 2

 For the purpose of this report, we use the term “improper payments” to encompass both 

erroneous payments caused by eligibility errors and improper payments resulting from
 

potential fraud. 

3 Office of Inspector General (OIG) analysis based on CMS numbers, Fiscal Year 2013 

Agency Financial Report, December 16, 2013, p. 173. 4

 There are conditions under which States may pay for services received by a beneficiary
 

in more than one State, which include, but are not limited to, medical emergencies. 

42 CFR § 431.52. 

5

 Puerto Rico is the only United States territory participating in PARIS. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 1 
 

 

 

 

 

 

 

programs. PARIS consists of three types of matches—a Federal Match,6 a 

Veterans Affairs Match,7 and an Interstate Match. The Interstate Match 

provides States with information about individuals who are enrolled in 

various types of State health and public assistance programs in multiple 

States. One type of Interstate Match is the Medicaid Interstate Match, 

which takes Medicaid enrollment data from one State and matches it to 

Medicaid enrollment data from other States to identify beneficiaries who 

are enrolled in multiple State Medicaid programs.8 

The Administration for Children and Families (ACF). ACF, an agency 

within HHS, facilitates the PARIS matches and provides information to 

States about PARIS. As part of its responsibilities for Federal programs 

that promote the economic and social well-being of children, families, and 

communities, ACF coordinates with States to ensure that they sign the 

required annual memorandums of understanding to participate in the 

PARIS matches.9 ACF also maintains a Web site and sponsors an annual 

conference to provide information to States regarding PARIS. 

Federal Requirements for the Medicaid Interstate Match 

State participation in the Medicaid Interstate Match is required by the 

Social Security Act (SSA) as a condition of receiving Medicaid funding for 

automated data systems.10 Effective October 1, 2009, the SSA required 

States to have a system for determining Medicaid eligibility that provides 

for data matching through PARIS or any successor system.11, 12 

6

 The Federal match provides States with information by matching State data with
 

information from the Department of Defense and the Office of Personnel Management. 

This match determines whether beneficiaries receive income from either of these sources 

or are eligible for Federal health care coverage. PARIS, Federal Match Files: User 

Manual, December 2008, p. 1. 7

 The Veterans Affairs match provides States with information on the eligibility of their 

public and medical assistance beneficiaries for veterans’ benefits and allows States to
 

confirm whether their beneficiaries receive income and/or medical assistance payments 

from the Department of Veterans Affairs. Altarum Institute, PARIS Cost-Benefit 

Analysis—Final Report, December 2008, p. 3.
 8

 The Interstate Match also matches enrollment data from the following public assistance 

programs: Temporary Assistance for Needy Families, the Supplemental Nutritional 

Assistance Program, the Childcare program, and Worker’s Compensation. 9 The annual memorandum of understanding certifies States’ compliance with procedures 

for information technology security. ACF, Memorandum of Understanding Interstate 

Data Matching by State Public Assistance Agencies. Accessed at 

http://www.acf.hhs.gov/programs/paris/appendix-3m on November 5, 2013. 10 SSA § 1903(r)(3). States may receive payments for automated data systems authorized
 

by SSA § 1903(a)(3) only if they meet the requirements of SSA § 1903(r)(3). 

11 As of the date of this report, a successor system does not exist for PARIS. 

12 SSA § 1903(r)(3). 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 2 
 

 

 

CMS Guidance for the Medicaid Interstate Match. CMS administers the 

Medicaid program and has the responsibility to issue guidance regarding 

States’ participation in the Medicaid Interstate Match. In June 2010, CMS 

issued a State Medicaid Director Letter (SMDL) to provide formal 

guidance to State Medicaid agencies on complying with the requirement at 

section 1903(r)(3) of the SSA that requires States to participate in PARIS. 

According to the guidance, each State must—to demonstrate compliance 

with the requirement—amend its Medicaid State plan to document its 

participation in PARIS.13 However, neither the SSA nor the SMDL 

defines the meaning of “participation” as it relates to the match. 

Medicaid Interstate Match Process 

States submit Medicaid enrollment data to the Defense Manpower Data 

Center (DMDC), which conducts the Medicaid Interstate Match.14 DMDC 

conducts quarterly matches in February, May, August, and November of 

each year. For each quarterly match, DMDC uses the enrollment data 

submitted by States and compares the Social Security Numbers (SSNs) of 

enrolled beneficiaries from one State to those of beneficiaries enrolled in 

other States, thereby identifying beneficiaries who are enrolled in multiple 

State Medicaid programs. For these beneficiaries, DMDC then generates 

matches that contain enrollment data from the States with Medicaid 

programs in which the beneficiary is enrolled. DMDC compiles the 

matches into a “match file” and sends it to the appropriate States. 

Reducing Improper Payments Through Participation in the 

Medicaid Interstate Match 

Although neither the SSA nor the June 2010 SMDL defines what 

constitutes State participation in the Medicaid Interstate Match, we 

identified four steps that States perform to reduce improper payments 

through their participation in the match. The four steps include 

(1) submitting Medicaid enrollment data to DMDC, (2) verifying matches 

(i.e., determining the Medicaid eligibility of the beneficiaries listed in the 

match file), (3) discontinuing Medicaid benefits for ineligible 

beneficiaries, and (4) recovering any improper Medicaid payments. 

Submitting Medicaid Enrollment Data. States receive an email from ACF 

that provides the deadline for submitting Medicaid beneficiaries’ 

enrollment data for each quarterly Medicaid Interstate Match. States 

participating in that quarterly match must electronically submit their 

13 CMS, SMDL: Public Assistance Reporting Information System (PARIS), 

SMDL#10-009, June 21, 2010. 

14 DMDC is a Department of Defense contractor that conducts all the PARIS matches. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 3 
 

 

 

 

 

 

enrollment data to DMDC by the deadline.15 At a minimum, States are 

expected to submit enrollment data for the quarterly match conducted in 

August of each year.16 Neither the SSA nor the SMDL indicates whether 

States are required to submit enrollment data for all of their Medicaid 

beneficiaries. 

The Medicaid enrollment data that States submit to DMDC for the 

Medicaid Interstate Match include a variety of information. Examples of 

the information include the beneficiary’s name, SSN, date of birth, 

address, sex, marital status, and Medicaid eligibility dates (i.e., the start 

and end dates of Medicaid coverage).17 

Verifying Matches. After State Medicaid agencies receive their match 

information from DMDC, agency staff may verify the matches 

(i.e., determine whether the beneficiary is eligible to receive benefits in 

their State). Because DMDC uses only the SSNs to identify beneficiaries 

who are enrolled in multiple State Medicaid programs, State Medicaid 

agency staff use the Medicaid eligibility dates in the match file to 

determine whether the beneficiaries’ coverage periods for their State 

overlap with those for other States.18 Overlapping coverage periods 

indicate that the beneficiary is simultaneously enrolled in multiple State 

Medicaid programs. Other verification activities can include requiring a 

beneficiary to come into the State Medicaid agency’s office to show proof 

of residency, mailing a residency verification letter to the beneficiary, 

and/or contacting another State to determine whether the beneficiary is 

still enrolled in that State’s Medicaid program. 

Discontinuing Medicaid Benefits. If State Medicaid agency staff verify a 

match and determine that a beneficiary is ineligible to receive Medicaid 

benefits in that State, they may initiate action to discontinue the 

beneficiary’s benefits.19 By discontinuing such benefits, States can reduce 

improper payments to the managed care organizations and fee-for-service 

providers that participate in their Medicaid programs. 

Recovering Improper Medicaid Payments. If State Medicaid agency staff 

determine that their program made improper payments for a beneficiary 

whose Medicaid benefits were discontinued, the State may attempt to 

recover these improper payments. States may treat these improper 

15 ACF, Instructions for DMDC electronic file transmission on the PARIS project. 

Accessed at http://www.acf.hhs.gov/programs/paris/instructions-for-dmdc-electronic-filetransmission on September 16, 2013. 16 Ibid. 

17 70 Fed. Reg. 40690 (July 14, 2005). 18 A coverage period is the period during which an individual is entitled to benefits. 

19 Government Accountability Office (GAO), PARIS Project Can Help States Reduce 

Improper Benefit Payments, GAO-01-935, September 2001, p. 5. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 4 
 

 

 

 

 

 

 

 

 

 

 

 

 

payments to managed care organizations and fee-for-service providers as 

overpayments, and recover them accordingly.20 Once an improper 

payment is identified, State Medicaid agency staff refer the matter to the 

appropriate State component to recover these Medicaid payments. The 

criteria for recovering improper Medicaid payments vary by State; 

therefore, not all improper payments may result in recoveries. 

Related Work 

In 2008, a series of OIG audits found that millions of dollars were paid for 

Medicaid services on behalf of beneficiaries who should not have been 

eligible because of their residency. One of these audits found that the 

District of Columbia paid $1.9 million from July 2005 to June 2006 for 

Medicaid services provided to beneficiaries who should not have been 

eligible because of their residency in Maryland.21 

Other reports have been issued saying that there are issues with how States 

verify matches from the PARIS Interstate Match. For example, in 2001, a 

GAO report found that States participating in PARIS gave little or no 

attention to interstate matches, allowing matches to go unresolved.22 Also, 

an ACF-commissioned report that looked at a sample of 14 States found 

that not all 14 were verifying the majority of the matches from the PARIS 

Interstate Match.23 

METHODOLOGY 

Scope 

Our evaluation is national in scope and focuses on States’ participation in 

the Medicaid Interstate Match. We used DMDC’s match files from the 

August 2011 match because States are expected to, at a minimum, 

20 SSA § 1128J, added by the Patient Protection and Affordable Care Act, P.L. 

No. 111-148 § 6402 (March 23, 2010), as amended by the Health Care Reconciliation 

Act of 2010, P.L. No. 111-152 (March 30, 2010), collectively known as the ACA. 

Overpayments are funds that a person receives or retains under the Medicaid program, to 

which the person, after applicable reconciliation, is not entitled. Once an overpayment is 

identified and not returned within the deadlines in SSA § 1128J(d)(2), the overpayment 

becomes a debt owed to the Federal Government. Under SSA § 1128J, beneficiaries are 

not liable for overpayments. 

21 OIG, Medicaid Payments for Services Provided to Beneficiaries With Concurrent 

Eligibility in the District of Columbia and Maryland for July 1, 2005, Through
 

June 30, 2006: The District of Columbia Department of Health, A-03-07-00214, 

April 2008, p. 3.
 22 GAO, PARIS Project Can Help States Reduce Improper Benefit Payments, 

GAO-01-935, September 2001, p. 15. 

23 Health Systems Research, Inc., an Altarum Company, Evaluation to Determine the 

Effectiveness of the Public Assistance Reporting and Information System—Final Report, 

June 2007, p. 34. Accessed at http://www.acf.hhs.gov/sites/default/files/files/ 

PARISFinal082007.pdf on September 18, 2013. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 5 
 

 

 

participate in this quarterly match.24, 25 To allow States adequate time to 

verify matches from the August 2011 match, we continued to collect data 

through November 2012. The findings in this report are projected to all 

the matches in the August 2011 match. 

Data Collection and Analysis 

We used three data sources for our analysis: (1) DMDC match files from 

the August 2011 match, (2) structured interviews with CMS officials, and 

(3) a survey of the 52 State Medicaid agencies. 

DMDC Match Files From the August 2011 Medicaid Interstate Match. To 

determine the extent to which States participate in the Medicaid Interstate 

Match, we obtained from DMDC all match files from the August 2011 

match and selected a simple random sample of 300 matches. Overall, the 

August 2011 match files identified 159,964 matches from all States. The 

sample of 300 matches allows us to project the results of our analysis 

nationally to all the matches in the Medicaid Interstate Match for that 

quarter. We are projecting only to those Medicaid beneficiaries whose 

enrollment data was submitted for the quarterly Medicaid Interstate Match 

conducted in August 2011. For the statistics we project in this report, the 

estimates and 95-percent confidence intervals are listed in Appendix A. 

For each match in the sample, we gathered information from all States that 

submitted Medicaid enrollment data for the beneficiary. For the 

beneficiaries in our sample of matches, we asked States whether they had 

verified the match(es) to determine the beneficiaries’ eligibility. If a State 

had done so and determined that a beneficiary was no longer eligible for 

benefits in its State, we asked whether the State discontinued the 

beneficiary’s benefits. If the State had discontinued the benefits, we asked 

it to provide the amount of improper Medicaid payments it made on behalf 

of the beneficiary and whether it recovered any of this amount. 

From the sample of matches and States’ responses, we projected the 

following information: 

	 the percentage of matches from the August 2011 match that States 

verified; and 

24 ACF, Instructions for DMDC electronic file transmission on the PARIS project. 

Accessed at http://www.acf.hhs.gov/programs/paris/instructions-for-dmdc-electronic-filetransmission on September 16, 2013. 25 We did not use DMDC’s match files from the August 2012 Medicaid Interstate Match. 

Using DMDC match files from that period would not have allowed sufficient time for 

States to verify the matches. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 6 
 

 the percentage of beneficiaries from the August 2011 match whose 

benefits were discontinued because their State determined that they 

were ineligible to receive Medicaid benefits in the State. 

We were unable to project the total amount of improper Medicaid 

payments made and recovered by States because States reported improper 

payments for only a limited number of matches. Therefore, our findings 

are limited to presenting the actual amounts of improper payments and of 

recoveries that States reported making based on our sample of 

300 matches from the August 2011 match. 

To identify issues that States encounter when verifying matches, we asked 

States to explain their reasons for not verifying each beneficiary’s 

Medicaid eligibility in our sample. We analyzed their responses and 

described the reasons States did not verify the eligibility of the 

beneficiaries. 

Structured Interviews With CMS Officials. We conducted structured 

interviews with CMS officials to determine the extent to which they 

provided guidance to States, beyond the SMDL, for participating in the 

Medicaid Interstate Match. We asked them to describe any guidance that 

they provided to States related to participating in the match, and we 

analyzed their responses. 

State Medicaid Agency Survey. We administered an electronic survey to 

Medicaid agency staff in all States to determine, for each of the four steps 

listed on pages 3–4, the extent to which they (1) have policies and 

procedures (policies), (2) experience barriers, and (3) receive guidance 

from CMS. If States reported that they had polices for any of the four 

steps, we asked them to provide their policies to us. We reviewed the 

policies to validate States’ responses and determined the number of States 

that had policies for each step. We asked States to describe any barriers 

they experienced for each of the four steps, and we analyzed their 

responses to determine the type of any such barriers. We asked States 

what type of additional guidance, if any, they would like to receive related 

to the Medicaid Interstate Match. We analyzed survey responses to 

calculate the number of States that wanted to receive such guidance and to 

determine the types of such guidance. 

We asked States to provide us with copies of their amendment to their 

Medicaid State plan that documents their participation in PARIS. We 

calculated the number of States that submitted such an amendment. We 

reviewed the amendments to determine the extent to which States 

addressed one or more steps related to participating in the Medicaid 

Interstate Match. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 7 
 

 

To determine whether States submitted Medicaid enrollment data for all of 

their beneficiaries, we asked each State to provide us with (for the 

August 2011 match) (1) the total number of beneficiaries enrolled in its 

State Medicaid program and (2) the total number of such beneficiaries for 

whom it submitted enrollment data for the match. To determine how 

many States did not submit enrollment data for all of their beneficiaries, 

we took the total number of beneficiaries enrolled in each State’s 

Medicaid program and subtracted the total number of beneficiaries for 

whom the State submitted data for the match. 

We received survey responses from all States. 

Limitations 

We did not determine the validity of the matches from the August 2011 

Medicaid Interstate Match. Our analysis of the survey of State Medicaid 

agencies and the information we gathered on our sample of matches is 

based on self-reported data as of November 2012. We did not 

independently verify the accuracy of the survey data. We could not 

determine States’ full compliance with the SSA because neither the SSA 

nor CMS guidance defines the meaning of “participation” as it relates to 

the Medicaid Interstate Match. 

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. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 8 
 

FINDINGS 

States’ participation in the Medicaid Interstate Match is 

limited 

State participation in the Medicaid Interstate Match is required as a 

condition of receiving Medicaid funding for automated data systems. This 

match has the potential to identify beneficiaries who may be enrolled in 

multiple State Medicaid programs and thus to enable States to reduce 

improper payments. In analyzing how States perform the four steps to 

reduce improper payments through the match, we found that States’ 

participation in the August 2011 match was limited. Specifically, States 

did not (1) submit Medicaid enrollment data for all beneficiaries; 

(2) verify more than half the matches (to determine beneficiaries’ 

Medicaid eligibility); (3) discontinue beneficiaries’ benefits for over half 

the verified matches; or (4) recover any improper payments. 

Fourteen States did not submit Medicaid enrollment data for 

all beneficiaries in their State; five States reported that barriers 

related to resources or technical capability limited their ability 

to submit Medicaid enrollment data 

While all States submitted Medicaid enrollment data for the August 2011 

match, 14 States did not submit enrollment data for all of their 

beneficiaries. These 14 States did not submit between 1 and 85 percent— 

with an average of 46 percent and a median of 11 percent—of the 

Medicaid enrollment data for their beneficiaries. For example, one State 

did not submit enrollment data for 79 percent of its Medicaid beneficiaries 

(7 million of 9 million).26 Another State did not submit enrollment data 

for 66 percent of its beneficiaries (650,000 of 988,000). To maximize the 

potential for the Medicaid Interstate Match to identify beneficiaries who 

may be enrolled in multiple State Medicaid programs, each State needs to 

submit complete enrollment data for all of its beneficiaries. 

Among the 14 States that did not submit Medicaid enrollment data for all 

of their beneficiaries, 5 States reported that barriers related to resources or 

to technical capability limited their ability to submit data to DMDC. For 

example, one State Medicaid agency reported that it lacked staff to prepare 

the enrollment data for submission. Another State reported that it does not 

submit enrollment data from one of its two Medicaid enrollment systems 

because the system does not have the technical capability to display 

information that it receives from DMDC. 

26 Medicaid enrollment figures provided by the State are rounded. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 9 
 

States did not verify almost 70 percent of the matches because 

of issues with the enrollment data 

States did not verify 68 percent of the matches from the August 2011 

match because issues with the enrollment data led States to determine that 

the matches no longer merited verification. The most common reason that 

States did not verify matches was that States submitted enrollment data for 

beneficiaries who were no longer enrolled in—or soon to be no longer 

enrolled in—their Medicaid programs. The second most common reason 

that States did not verify matches was that States submitted incomplete or 

inaccurate enrollment data (e.g., incorrect SSNs). 

With regard to the matches that were not verified, States did not verify 

56 percent of those because the Medicaid eligibility dates for the 

beneficiaries indicated that they were no longer enrolled in—or would 

soon no longer be enrolled in—the program for at least one of the States 

for which there was a match. When a State submits Medicaid eligibility 

dates that indicate that the beneficiary is no longer enrolled in its Medicaid 

program, it can create a “false positive” match. When another State 

examines this match and finds that the eligibility dates indicate that the 

beneficiary will soon no longer be enrolled in at least one of the States’ 

Medicaid programs, that State may conclude that the match does not merit 

the resources for verification. 

Of the matches that were not verified, States did not verify 17 percent of 

those because the match was associated with incomplete or inaccurate 

Medicaid eligibility dates or inaccurate SSNs. When a State submits 

incomplete or inaccurate eligibility dates for beneficiaries who are 

included on the match file, it is difficult for other States to determine 

whether such beneficiaries have an overlapping Medicaid coverage period. 

States must then conduct resource-intensive followup activities, which 

may include obtaining additional information from other States. 

Therefore, given their limited information and resources, States may 

conclude that these matches also do not merit verification. One State said: 

“When the data is not accurate or reliable, [conducting verification] is not 

an efficient use of [State Medicaid agency] staff time.” 

Less than half the verified matches resulted in States’ 

discontinuing beneficiaries’ benefits 

States reduce improper payments through participation in the Medicaid 

Interstate Match when one or more States discontinue the Medicaid 

benefits of beneficiaries who are found to be enrolled in multiple State 

Medicaid programs. While States verified 32 percent of the matches from 

the August 2011 match, only 41 percent of those matches resulted in a 

discontinuation of benefits. Forty-nine percent of the matches verified did 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 10 
 

 

 

not result in a discontinuation of benefits because they were verified by 

only one of the States in which the beneficiary was enrolled, and that State 

was not the one that needed to discontinue benefits.27 For the process to 

accurately identify beneficiaries who are improperly enrolled in multiple 

State Medicaid programs, each State that is flagged in a given match must 

verify the match to determine whether it needs to discontinue the 

beneficiary’s benefits. 

See Appendix B for the number of projected matches for the August 2011 

match that are associated with the above percentages for verified and 

unverified matches. 

States did not recover any improper Medicaid payments 

To maximize the potential for reducing improper payments through 

participation in the Medicaid Interstate Match, States may recover 

improper payments made on behalf of beneficiaries found to be ineligible. 

For 41 percent of the verified matches from the August 2011 match that 

resulted in a discontinuation of benefits, States had made improper 

payments on behalf of beneficiaries. However, States provided the 

amount of improper payments for only 18 percent of these matches,28 

which totaled $6,200 in improper Medicaid payments. Although this 

amount is small, we do not know the amount of improper payments for the 

other 82 percent of the verified matches that resulted in a discontinuation 

of benefits. Furthermore, all of the beneficiaries associated with the 

$6,200 in improper payments were enrolled in Medicaid managed care 

programs. States reported that in these cases, they did not recover any 

improper payments from the managed care organizations because of 

barriers such as lack of resources and length of time needed to recover 

improper payments. This suggests that if the States had not discontinued 

these beneficiaries’ benefits, they potentially would have made additional 

unrecoverable improper payments. 

CMS guidance to States for participating in the 

Medicaid Interstate Match is limited; States reported 

that they needed more guidance 

In June 2010, CMS issued an SMDL to provide guidance to State 

Medicaid agencies on complying with the SSA’s requirement that States 

participate in PARIS. The guidance requires States to amend their 

respective Medicaid State plans to document their participation in PARIS, 

27 For 10 percent of the matches that were verified, States did not provide us with 

information to determine whether the beneficiaries’ Medicaid benefits were discontinued. 

28 States did not provide the amounts of improper payments for enough matches to 

project the total amount of improper payments for the August 2011 match. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 11 
 

 

 

but it does not address any of the four steps related to reducing improper 

payments through participation in the Medicaid Interstate Match. In the 

absence of specific guidance, only four States have amended their 

respective State plans to include language that addresses one or more of 

the four steps.29 

Twenty-two of the fifty-two States reported they would like additional 

guidance related to one or more of the steps for participating in the 

Medicaid Interstate Match. See Table 1 for each step and the 

corresponding number of States that would like additional guidance. 

Table 1. Number of States That Would Like To Receive Guidance 

Regarding Steps Related to Participation in the Medicaid Interstate Match 

Step Related to Participation in the 

Medicaid Interstate Match 

Number of States 

That Would Like To 

Receive Guidance 

Regarding Step 

Submitting Medicaid enrollment data 7 

Verifying matches 20 

Discontinuing benefits 22 

Recovering improper payments 21 

Source: OIG analysis of survey data, 2013. 

Note: Categories are not mutually exclusive. Therefore, the total number of
 

States exceeds 52.
 

Most States had policies addressing at least one of

the steps for participating in the Medicaid Interstate

Match 

Thirty-four of the fifty-two States had policies addressing at least one of 

the steps to reduce improper payments through participation in the 

Medicaid Interstate Match. Nine of those States had policies related to all 

four steps. Almost half of all States had policies on submitting Medicaid 

enrollment data. More than half of all States had policies on verifying 

matches, and more than a third of all States had policies on discontinuing 

benefits and policies on recovering improper payments. See Table 2 for 

the number of States that had policies addressing each of the four steps for 

participating in the match. 

29 In addition, CMS guidance did not set a deadline for States to amend their respective 

Medicaid State Plans. In the absence of such a deadline, 15 States had not amended their 

plans as of November 2012. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 12 
 

Table 2. Number of States That Have Policies Regarding Steps Related to 

the Medicaid Interstate Match 

Step Related to Participation in the 

Medicaid Interstate Match 

Number of States 

With Policies 

Regarding Step 

Submitting Medicaid enrollment data 25 

Verifying matches 27 

Discontinuing benefits 19 

Recovering improper payments 20 

Source: OIG analysis of PARIS policies, 2013. 

Note: Categories are not mutually exclusive. Therefore, the total number
 

of States exceeds 52. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 13 
 

CONCLUSION AND RECOMMENDATION 

State participation in the Medicaid Interstate Match is required unless 

PARIS is succeeded by a system that provides for data matching to 

identify beneficiaries who may be enrolled in multiple State Medicaid 

programs. As of the date of this report, there is no such successor 

system. The match provides States with an opportunity to reduce 

improper Medicaid payments. However, State participation in the match 

is limited. States do not consistently perform all four steps to reduce 

improper payments. Furthermore, CMS guidance does not define the 

meaning of “participation” as it relates to the match. 

For States to receive the full benefit of their participation in the Medicaid 

Interstate Match, CMS needs to provide additional guidance to States that 

helps maximize the match’s potential to accurately identify beneficiaries 

who are enrolled in multiple States. States did not verify the majority of 

matches from the August 2011 match because they concluded that these 

matches did not merit verification. Guidance to States that helps improve 

the accuracy of the matches would likely increase the usefulness of the 

match. Until a successor system exists for PARIS, we recommend that 

CMS: 

Issue Guidance to States on the Requirement for Participating 

in the Medicaid Interstate Match 

Guidance from CMS could assist States in complying with the 

requirement for participating in the Medicaid Interstate Match. This 

guidance also could help States receive the full benefit of their 

participation. Until PARIS is succeeded by another system, CMS should 

define the meaning of “participation” in the match by establishing clear 

expectations for the actions that States should take to comply with the 

requirement. CMS should then issue guidance to States on its 

expectations for State participation in the match. In addition to assisting 

States in achieving compliance, guidance would also help ensure that 

States develop consistent policies regarding the match. 

CMS guidance should address the following steps: 

Submitting Medicaid Enrollment Data to DMDC. Guidance for 

submitting enrollment data should clarify whether States should submit 

Medicaid enrollment data for all of their beneficiaries. Guidance that 

requires States to do so would maximize the potential of the match to 

identify all beneficiaries who may be enrolled in multiple State Medicaid 

programs. Guidance also should clarify what data States should submit 

for the match. Submitting consistent, accurate, and complete enrollment 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 14 
 

data for the match could potentially (1) generate the most accurate 

matches and (2) reduce the amount of time needed to verify matches. 

Verifying Matches Identified by the Medicaid Interstate Match. After 

CMS issues guidance for the submission of Medicaid enrollment data, it 

should issue guidance requiring States to verify matches to determine 

beneficiaries’ Medicaid eligibility. CMS could also provide guidance to 

States on how to track match-related activities and timelines for verifying 

matches. This type of guidance could result in the prompt verification and 

discontinuation of Medicaid benefits, which could reduce the length of 

time when beneficiaries are enrolled in multiple State Medicaid programs 

and thus ultimately reduce the amount of improper payments. 

Discontinuing Benefits and Recovering Improper Payments. Although 

States vary in their systems and processes for discontinuing benefits and 

recovering improper payments, CMS could gather information from States 

regarding their best practices for these tasks. Working with States to 

develop guidance may result in fewer improper payments and/or in more 

money being returned to Federal and State governments. As appropriate, 

CMS could include the best-practices information in its guidance to States 

on these topics. CMS could also collaborate with ACF to provide 

additional guidance through the PARIS Web site and annual conference. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 15 
 

 

AGENCY COMMENTS AND OFFICE OF INSPECTOR GENERAL 

RESPONSE 

CMS concurred with our recommendation that it issue guidance to States 

on the requirement for participating in the Medicaid Interstate Match. 

For the full text of CMS’s comments, see Appendix C. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 16 
 

 

APPENDIX A 

Confidence Intervals 

Estimate Description Sample Size Point 

Estimate 

95-Percent 

Confidence 

Interval 

Matches that States did not verify primarily 

because of barriers with the Medicaid enrollment 

data 

300 matches 68% 62.3%–73.0% 

Matches that were not verified because the 

Medicaid eligibility dates on the match file 

indicated that the beneficiary was no longer 

enrolled or would soon no longer be enrolled in 

the Medicaid program for at least one of the 

States for which there was a match 

203 matches that 

were not verified 56% 49.2%–63.0% 

Matches that were not verified because the 

match was associated with missing or inaccurate 

Medicaid eligibility dates or inaccurate SSNs 

203 matches that 

were not verified 18% 12.0%–23.0% 

Matches that States verified 300 matches 32% 27.0%–37.7% 

Matches that did not result in a discontinuation 

of benefits because they were verified by only 

one of the States in which the beneficiary was 

enrolled 

97 matches that 

were verified 49% 38.3%–59.0% 

Matches that resulted in a discontinuation of 

benefits 

97 matches that 

were verified 41% 31.3%–51.2% 

Source: OIG analysis of match data, 2013. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 17 
 

 

 

APPENDIX B 

Number of Projected Matches for the August 2011 Medicaid 

Interstate Match 

Estimate Description 

Projected 

Number of 

Matches 

(n=159,964) 

Number of 

Matches from 

the Sample 

(n=300) 

Matches that States did not verify 108,776 203 

Matches that were not verified because the 

Medicaid eligibility dates on the match file indicated 

that the beneficiary was no longer enrolled or would 

soon no longer be enrolled in the Medicaid program 

for at least one of the States for which there was a 

match 

60,915 203 

Matches that were not verified because the match 

was associated with incomplete or inaccurate 

Medicaid eligibility dates or inaccurate SSNs 

18,492 203 

Matches States verified 51,189 97 

Matches that did not result in a discontinuation of 

benefits because they were verified by only one of 

the States in which the beneficiary was enrolled 

25,082 47 

Matches that resulted in a discontinuation of 

benefits 20,987 40 

 Source: OIG analysis of match data, 2013. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 18 
APPENDIXC 

Agency Comments 

c~.~~ DEPARTMENT OF HEALTH & HUMAN SERVICE_s________c_e_nt-er_s_to_r_M_ed-ic_a_r•_&_M_e_d_ic_ai_d_s_eTV_i_c•_• 

s~ Administrator 

Washington. DC 20201 

DATE: JUN 11 2014 

TO: 	 Daniel R. Levinson 


Inspector General 


FROM: 	 Ma'ld.Jyn Tavenner 


Administretdr 


SUBJECT: 	 Office of the Inspector General (OIG) Draft Report: "Public Assistance Reporting 

Information System: State Participation in the Medicaid Interstate Match is 

Limited" (OEI-09-11-00780) 

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

comment on the above-referenced OIG draft report. OIG's report focuses on states' participation 

in the Medicaid Interstate Match. This is a tool used to reduce improper Medicaid payments, 

made as a result of one type of eligibility error. by identifYing beneficiaries who are enrolled in 

multiple state Medicaid programs. The findings and recommendations focus primarily on states' 

use of the tool, rather than on actual eligibility errors resulting from states' failure to use it. 

The report did find that, in its sample from August 2011, states did make improper payments for 

beneficiaries for whom interstate matches (i.e., evidence that the beneficiary was enrolled in 

more than one state) ultimately resulted in a discontinuation of benefits. However, states only 

provided the amount of improper payments for 18 percent ofthese matches, which totaled 

$6.200 in improper Medicaid payments. 

The report does not seem to have enough information to adequately determine the real scope of 

eligibility errors resulting from inadequate use of the Medicaid Interstate Match; but, based on its 

findings, OIG did conclude that states' participation is limited and that states need more 

guidance from CMS about such participation. 

OIG Recommendation 

The OIG recommends that CMS issue guidance to states on the requirement for participating in 

the Medicaid Interstate Match. 

CMS Response 

The CMS concurs with OIG's recommendation that CMS issue further guidance to states to 

clarify the requirement for participating in the Medicaid Interstate Match. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 19 
 

Agency Comments (continued) 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 20 
 

ACKNOWLEDGMENTS 

This report was prepared under the direction of Timothy Brady, Regional 

Inspector General for Evaluation and Inspections in the San Francisco 

regional office, and Michael Henry, Deputy Regional Inspector General. 

China Tantameng served as the team leader for this study, and 

Veronica Gonzalez served as the lead analyst. Other Office of Evaluation 

and Inspections staff from the San Francisco regional office who 

conducted the study include Christina Lester and Tiffany Stanley. Central 

office staff who provided support include Clarence Arnold, Kevin Manley, 

and Christine Moritz. 

PARIS: State Participation in the Medicaid Interstate Match Is Limited (OEI-09-11-00780) 21 
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.