U.S. Department of Health and Human Services 
Office of Inspector General 
 
Some Medicare Advantage 
Organization Denials of Prior 
Authorization Requests Raise 
Concerns About Beneficiary 
Access to Medically Necessary 
Care 
 
Christi A. Grimm 
Inspector General 
A pril 2022, OEI-09-18-00260 
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Ap ril 2022, OEI-09-18-00260 
 
     
Some Medicare Advantage Organization 
Why OIG Did This Review 
A   centr al concern about th e 
Denials of Prior Authorization Requests 
capitated payment model used in 
Medicare Advantage is the  Raise Concerns About Beneficiary Access to 
potential incentive for Medicare 
Medically Necessary Care  
Advantage Organizations (MAOs) 
to deny beneficiary access to 
What OIG Found 
services and deny payments to  Key Takeaway 
Our case file reviews determined 
providers in an attempt to increase 
MAOs denied prior  that MAOs sometimes delayed or 
profits.  Although MAOs approve 
authorization and payment  denied Medicare Advantage 
the vast majority of requests for 
requests that met Medicare  beneficiaries access to services, 
services and payment, they issue 
coverage rules by:  even though the requests met 
millions of denials each year, and 
CMSs annual audits of MAOs have    using MAO clinical criteria  Medicare coverage rules.  MAOs 
highlighted widespread and  that are not contained in  also denied payments to providers 
persistent problems related to  Medicare coverage rules;   for some services that met both 
Medicare coverage rules and MAO 
inappropriate denials of services    requesting unnecessary 
billing rules.  Denying requests that 
and payment.  As enrollment in  documentation; and  
meet Medicare coverage rules may 
Medicare Advantage continues to    making manual review 
prevent or delay beneficiaries from 
grow, MAOs play an increasingly  errors and system errors. 
receiving medically necessary care 
critical role in ensuring that 
and can burden providers.  
Medicare beneficiaries have access 
Although some of the denials that 
to medically necessary covered 
we reviewed were ultimately reversed by the MAOs, avoidable delays and 
services and that providers are 
extra steps create friction in the program and may create an 
reimbursed appropriately.   
administrative burden for beneficiaries, providers, and MAOs.  Examples 
How OIG Did This Review  of health care services involved in denials that met Medicare coverage 
We selected a stratified random  rules included advanced imaging services (e.g., MRIs) and stays in post-
sample of 250 denials of prior  acute facilities (e.g., inpatient rehabilitation facilities).   
authorization requests and 
250 payment denials issued by  Prior authorization requests.  We found that among the prior 
15 of the largest MAOs during  authorization requests that MAOs denied, 13 percent met Medicare 
June 17, 2019.  Health care coding  coverage rulesin other words, these services likely would have been 
experts reviewed case files for all  approved for these beneficiaries under original Medicare (also known as 
cases, and physician reviewers  Medicare fee-for-service).  We identified two common causes of these 
examined medical records for  denials.  First, MAOs used clinical criteria that are not contained in 
a subset of cases.  From these  Medicare coverage rules (e.g., requiring an x-ray before approving more 
results, we estimated the rates at  advanced imaging), which led them to deny requests for services that our 
which MAOs denied prior  physician reviewers determined were medically necessary.  Although our 
authorization and payment  review determined that the requests in these cases did meet Medicare 
requests that met Medicare  coverage rules, CMS guidance is not sufficiently detailed to determine 
coverage rules and MAO billing  whether MAOs may deny authorization based on internal MAO clinical 
rules.  We also examined the  criteria that go beyond Medicare coverage rules. 
reasons for these denials and the 
types of services associated with 
these denials in our sample. 
  Second, MAOs indicated that some prior authorization requests did not 
have enough documentation to support approval, yet our reviewers 
found that the beneficiary medical records already in the case file were 
sufficient to support the medical necessity of the services.   
Payment requests.  We found that among the payment requests that 
MAOs denied, 18 percent met Medicare coverage rules and MAO billing 
rules.  Most of these payment denials in our sample were caused by 
human error during manual claims-processing reviews (e.g., overlooking 
a document) and system processing errors (e.g., the MAOs system was 
not programmed or updated correctly).   
We also found that MAOs reversed some of the denied prior 
authorization and payment requests that met Medicare coverage rules 
and MAO billing rules.  Often the reversals occurred when a beneficiary 
or provider appealed or disputed the denial, and in some cases MAOs 
identified their own errors.   
What OIG Recommends 
Our findings about the circumstances under which MAOs denied 
requests that met Medicare coverage rules and MAO billing rules provide 
an opportunity for improvement to ensure that Medicare Advantage 
beneficiaries have timely access to all necessary health care services, and 
that providers are paid appropriately.  Therefore, we recommend that 
CMS:  
(1) issue new guidance on the appropriate use of MAO clinical criteria in 
medical necessity reviews;  
(2) update its audit protocols to address the issues identified in this 
report, such as MAO use of clinical criteria and/or examining particular 
service types; and 
(3) direct MAOs to take steps to identify and address vulnerabilities that 
can lead to manual review errors and system errors.  
CMS concurred with all three recommendations. 
 
   
  TABLE OF CONTENTS 
BACKGROUND  1 
Methodology  5 
FINDINGS  9 
Thirteen percent of prior authorization denials were for service requests that met Medicare  9 
coverage rules, likely preventing or delaying medically necessary care for Medicare Advantage 
beneficiaries 
Eighteen percent of payment denials were for claims that met Medicare coverage rules and  12 
MAO billing rules, which delayed or prevented payments for services that providers had 
already delivered   
Imaging services, stays in post-acute facilities, and injections were three prominent service  14 
types among the denials that met Medicare coverage rules 
MAOs reversed some initial prior authorization denials and payment denials for requests that  18 
met Medicare coverage rules and MAO billing rules 
CONCLUSION AND RECOMMENDATIONS FOR CMS   20 
Issue new guidance on the appropriate use of MAO clinical criteria in medical necessity  20 
reviews 
Update its audit protocols to address the issues identified in this report, such as MAO use of  21 
clinical criteria, and/or examine particular service types  
Direct MAOs to take additional steps to identify and address vulnerabilities that can lead to  21 
manual review errors and system errors 
AGENCY COMMENTS AND OIG RESPONSE  23 
DETAILED METHODOLOGY  24 
APPENDICES  31 
A.  Point Estimates and Confidence Intervals for Denials of Prior Authorization and Payment  31 
Requests That Met Medicare Coverage Rules, Issued by 15 Selected MAOs During June 17, 
2019 
B.  Detailed Descriptions of Denials for Requests That Met Medicare Coverage Rules   32 
C.  Characteristics of Sampled MAOs   52 
D.  Agency Comments  53 
ACKNOWLEDGMENTS AND CONTACT  56 
ABOUT THE OFFICE OF INSPECTOR GENERAL  57 
 
  BACKGROUND 
Objectives 
1.  To determine the extent to which selected Medicare Advantage 
Organizations (MAOs) denied prior authorization requests for services 
that met Medicare coverage rules, and to examine why these denials 
occurred. 
2.  To determine the extent to which the selected MAOs denied payment 
requests that met Medicare coverage rules and MAO billing rules, and 
to examine why these denials occurred. 
3.  To describe the types of health care services involved in denials of 
services and payments that met Medicare coverage rules and MAO 
billing rules. 
 
Enrollment in Medicare Advantage (also known as Medicare Part C) has continued to 
increase over the last decade (see Exhibit 1).  Of all Medicare beneficiaries in 2021, 
42 percent (26.4 million) were enrolled in a Medicare Advantage plan.  The 
Congressional Budget Office projects that the share of all Medicare beneficiaries 
enrolled in Medicare Advantage plans will rise to about 51 percent by 2030.1   
Exhibit 1:  Total Medicare Advantage enrollment has more than doubled since 
2011; Medicare Advantage covered 26.4 million beneficiaries in 2021. 
 
Source: Kaiser Family Foundation, Medicare Advantage in 2021: Enrollment Update and Key Trends, June 2021. 
 
1 Kaiser Family Foundation, Medicare Advantage in 2021: Enrollment Update and Key Trends, June 2021. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Background | 1  The Medicare program covers a wide range of health care services when they are 
medically necessary for beneficiaries.  Medicare Advantage is designed to cover the 
same services as original Medicare (also known as fee-for-service Medicare), but in 
Medicare Advantage, MAOs2 are also responsible for the coordination of care for 
beneficiaries enrolled in their plans.3, 4  The goal of coordinated care is to provide 
efficient, high-quality care that improves patient health outcomes while also 
managing program costs.  To manage care for beneficiaries and to help control costs, 
MAOs may impose additional requirements, such as requiring that beneficiaries use 
only in-network providers for certain health care services; requiring prior 
authorization before certain services can be provided; or requiring referrals for 
specialty care services.   
Although MAOs approve the vast majority of prior authorization requests and 
provider payment requests, MAOs also deny millions of requests each year.  A central 
concern about capitated payment modelsincluding the model used in Medicare 
Advantageis the potential incentive for insurers to deny access to services and 
payment in an attempt to increase profits.5  The Centers for Medicare & Medicaid 
Services (CMSs) annual audits of MAOs have highlighted widespread and persistent 
problems related to inappropriate denials of services and payment.6  This report 
focuses on the subset of prior authorization requests and provider payment requests 
that MAOs denied.  We examined these denied requests to assess the extent to which 
the denied requests met Medicare coverage rules, and thus would likely have been 
approved in original Medicare.  
Medicare Coverage Rules  
MAOs must follow Medicare coverage rules, which specify what items and services are 
covered and under what circumstances.  Because MAOs must provide beneficiaries 
with all basic benefits covered under original Medicare, they may not impose 
limitationssuch as waiting periods or exclusions from coverage due to pre-existing 
conditionsthat are not present in original Medicare.7  Medicare coverage rules are 
outlined in national coverage determinations (NCDs); local coverage determinations 
(LCDs) in the geographic area in which the MAO operates; the Medicare Benefit Policy 
Manual; the Medicare Managed Care Manual; legislative changes in benefits applied 
 
2 For the purposes of this report, we use MAO to mean a parent company that operates one or more 
Medicare Advantage contracts. 
3 At a minimum, MAOs must cover the same services as in original Medicare, although they may also 
offer supplemental benefits.  42 CFR  422.101(a) and (b); 422.102.  MAOs are not responsible for paying 
hospice care costs for beneficiaries; these costs are paid by original Medicare. 
4 CMS, Medicare Managed Care Manual, ch. 5, sec. 10. 
5 In capitated payment models, insurance companies or providers receive a fixed amount of money per 
patient regardless of the number of services provided to the patient. 
6 OIG, Medicare Advantage Appeal Outcomes and Audit Findings Raise Concerns About Service and 
Payment Denials, September 2018. 
7 CMS, Medicare Managed Care Manual, ch. 4, sec. 10.2. p. 7. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Background | 2  through notice-and-comment rulemaking, and other coverage guidelines and 
instructions issued by CMS.8  Coverage rules can include administrative requirements 
(e.g., requiring that a specific form be completed) and clinical requirements (e.g., 
outlining the types of cancer for which Medicare will cover chemotherapy).9   
MAO Clinical Criteria and Billing Rules 
Although MAOs must follow Medicare coverage rules, they are also permitted to use 
additional clinical criteria that were not developed by Medicare when they are 
determining whether to authorize or pay for a service, as long as such criteria are no 
more restrictive than original Medicares national and local coverage policies.10  For 
example, MAOs may develop and use their own internal clinical criteria or use 
commercially available clinical guidelines developed by private health care 
management companies.  (This report uses the term MAO clinical criteria to refer to 
any clinical criteria that MAOs adopt.)  MAO clinical criteria are typically more detailed 
than Medicare coverage rules and are intended to assist with clinical decision making.  
MAOs must provide beneficiaries with an annual Evidence of Coverage document that 
gives an overview of coverage requirements and beneficiary cost-sharing.11 
MAOs may create their own billing and payment procedures as long as all providers 
are paid accurately, timely, and with an audit trail.12  Providers must follow MAO 
billing rules, such as those outlined in provider contracts (e.g., payment requests must 
be filed within specific timeframes).  MAOs may also require that providers adhere to 
Medicare billing rules, such as the Medicare Claims Processing Manual.   
MAO Coverage Determination Process 
MAOs must establish procedures for making decisionsalso called coverage 
determinationsabout whether to approve or deny requests.13  MAOs issue coverage 
determinations for two types of requests: (1) prior authorization requests, which are 
requests for the MAO to preapprove a service or item before the beneficiary receives 
 
8 CMS, Medicare Managed Care Manual, ch. 4, secs. 90.2 and 90.3.  National Coverage Determinations are 
Department of Health and Human Services determinations on whether a particular item or service is 
covered under Medicare.  Local coverage determinations are written coverage decisions of local 
Medicare Administrative Contractors with jurisdiction for claims in a particular geographic area. MAOs 
are responsible for monitoring CMSs national coverage determinations and publications to ensure that 
they are complying with all Medicare coverage rules.  
9 If Medicare coverage rules do not exist for a specific service, then MAOs must determine whether the 
requested service is reasonable and necessary for the beneficiary and may use the coverage policies of 
other MAOs in their service area or other authoritative evidence such as peer-reviewed clinical studies.  
Social Security Act  1862(a)(1)(A).  CMS, Medicare Managed Care Manual, ch. 4, sec. 90.5. 
10 CMS, Medicare Managed Care Manual, ch. 4, sec. 10.16. 
11 42 CFR  422.111. 
12 CMS, Medicare Managed Care Manual, ch. 4, sec. 10.2. 
13 42 CFR  422.566; CMS, Parts C & D Enrollee Grievances, Organization/Coverage Determinations, and 
Appeals Guidance, sec. 10.4.4. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Background | 3  it; and (2) payment requests from a provider for a service already delivered to the 
beneficiary.  CMS requires that MAOs have a medical director who is responsible for 
ensuring the clinical accuracy of all coverage determinations involving an assessment 
of medical necessity.14   
Prior authorization requests.  MAOs can require that providers receive authorization 
for certain services before the MAO will provide coverage and payment.15  Prior 
authorization is a utilization management tool that MAOs can use to control costs 
and ensure the most cost-effective, clinically appropriate treatment is offered to 
beneficiaries.  Prior authorization requests are reviewed by MAO clinical staff to 
determine whether items and services are medically necessary and reasonable for the 
beneficiary, and whether they meet Medicare and MAO coverage rules.  For context, 
in 2018, MAOs denied 1.5 million prior authorization requests overall (5 percent of all 
prior authorization requests) in the Medicare Advantage program.16, 17 
Payment requests.  Providers who are paid on a fee-for-service basis by the MAO 
submit payment requests to receive reimbursement for services that the providers 
have already delivered to beneficiaries.  As with the MAOs decision on a prior 
authorization request, the MAOs decision to approve or deny the payment request 
must be consistent with applicable rules for Medicare coverage and MAO billing.  For 
context, in 2018, MAOs denied 56.2 million payment requests overall (9.5 percent of 
all payment requests) in the Medicare Advantage program.18 
Appeals.  When an MAO denies a prior authorization request, the beneficiary may 
elect not to receive the service; the beneficiary may elect to receive the service and 
pay for it out of pocket; or the beneficiary or the beneficiarys representative can file 
an appeal of the denial with the MAO.19  Similarly, when MAOs deny payment 
requests, providers can dispute or appeal the denial.  Providers who enter into a 
contract with an MAO (i.e., in-network providers) can file a payment dispute, which is 
processed and resolved according to the provisions in the MAOs provider manual or 
other document that delineates the MAO-specific dispute process.  Providers who do 
not have a contract with an MAO can file an appeal of the denial.   
 
14 42 CFR  422.562; CMS, Medicare Managed Care Manual, ch. 4, sec. 10.16. 
15 CMS, Medicare Managed Care Manual, Chapter, ch. 4, sec. 110.1.1.   
16 CMS, 2018 Part C Reporting Requirements Data, accessed on June 3, 2021.  In 2019, CMS changed 
MAO data reporting requirements to exclude the reporting of payment requests from contracted 
providers.  Because our analysis includes payment requests from contracted providers, we analyzed 
CMSs data from 2018 to give context on overall MAO denial rates. 
17 In 2018, MAOs overturned 86,193 prior authorization denials following an appeal. 
18 CMS, 2018 Part C Reporting Requirements Data, accessed on June 3, 2021.  In 2018, MAOs overturned 
258,524 payment denials following an appeal.   
19 CMS, Parts C & D Enrollee Grievances, Organization/Coverage Determinations, and Appeals Guidance 
(cms.gov), p. 15.  Individuals who represent beneficiaries may either be appointed or authorized to act on 
behalf of the beneficiary in dealing with any of the levels of the appeals process.   
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Background | 4  CMS oversight 
CMS uses several tools to oversee the performance of MAOs and ensure that 
beneficiaries have access to necessary care.  CMS assigns an account manager and 
lead caseworker for each MAO contract.  Account managers monitor complaints from 
beneficiaries and work with MAOs to promote compliance with Medicare program 
requirements.   
Each year, CMS audits a sample of MAOs to measure an MAOs compliance with the 
terms of its contract with CMS.  During the audits, CMS evaluates MAO compliance 
with requirements associated with beneficiaries access to covered Medicare services, 
access to drugs, and other beneficiary protections required by Medicare.20  CMS 
requires MAOs to implement corrective action plans to address any audit violations 
and to demonstrate that they have substantially corrected deficiencies before the 
audit is officially closed.  CMS may impose civil money penalties and sanctions for 
serious violations identified through audits.   
Prior OIG work on denials in Medicare Advantage 
In a September 2018 report, we found that when beneficiaries and providers appealed 
denied requests in Medicare Advantage during 20142016, MAOs overturned about 
75 percent of their own prior authorization denials and payment denials.21  We also 
found that CMS cited more than half of audited MAO contracts in 2015 for 
inappropriately denying prior authorization and payment requests.  We 
recommended that CMS address persistent problems related to denials identified in 
its audits.  CMS responded that it had increased the penalties for MAO violations that 
prevent beneficiaries from accessing medically necessary services.  We also 
recommended that CMS enhance its oversight of MAO appeals data and provide 
beneficiaries with clear, easily accessible information about serious violations by 
MAOs.  As of March 2022, CMS had not yet implemented these recommendations.  
Methodology 
Scope 
Using a random sample of denials from the 1-week period of June 17, 2019, this 
report estimates the rate at which 15 of the largest MAOs denied prior authorization 
and payment requests that met Medicare coverage rules.  It also describes the causes 
 
20 CMS audits MAO compliance in several program areas, including Medicare Advantage (Part C) 
coverage determinations, appeals, and grievances.  CMSs annual audit enforcement reports are available 
at https://www.cms.gov/Medicare/Compliance-and-Audits/Part-C-and-Part-D-Compliance-and-
Audits/ProgramAudits.html.  During the audits, CMS reviews a sample of MAO denials to determine 
whether they were appropriate, but CMS does not calculate a rate of inappropriate denials. 
21 OIG, Medicare Advantage Appeal Outcomes and Audit Findings Raise Concerns About Service and 
Payment Denials, September 2018. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Background | 5  and other issues associated with these denials; prominent service types among these 
cases; and (when available) MAO-reported actual or estimated costs.   
Sample Selection 
We selected 15 of the largest MAOs by enrollment as the study population.  These 
MAOs accounted for nearly 80 percent of beneficiaries enrolled in Medicare 
Advantage as of June 2019, ranging in size from about 165,000 to nearly 6 million 
beneficiaries.   
To compile a sampling frame, we collected a list of all prior authorization denials and 
payment denials that each selected MAO issued during a 1-week period, June 17, 
2019.  We stratified the sample frame of nearly 283,000 total denials by type of 
request (prior authorization or payment) and MAO enrollment size.  We then selected 
a stratified random sample of 500 denial cases, consisting of 250 prior authorization 
denials and 250 payment denials.   
During our review, we identified 70 sampled cases that were ineligible for this study 
(e.g., denials of requests for supplemental benefits that are not covered in original 
Medicare) and excluded them from our analysis.  This resulted in a final sample of 
430 cases.   
See Detailed Methodology on page 24 for further information. 
Case File Collection and Preliminary Screening 
To conduct the case file reviews, we contracted with health care coding and billing 
professionals with expertise in Medicare coverage rules and with physicians.  (In this 
report, we refer to the first group as health care coding experts.)  Initially, the health 
care coding experts checked whether a case was eligible for our sample.  Then they 
reviewed the case files of the 430 eligible cases for completeness and made additional 
requests to the MAOs for missing records or information needed for case file reviews.   
Case File Reviews 
To design the case file review methodology, we consulted with the following: CMS; 
the Medicare Advantage Independent Review Entity contractor (which reviews 
appeals that were upheld by MAOs); physicians; and health care coding experts.  We 
also reviewed CMS policy documents such as the Medicare Managed Care Manual. 
The objective of the case file reviews was to determine whether the denied prior 
authorization and payment requests met relevant Medicare coverage rules and, if 
applicable, MAO billing rules.  For our sample of 430 eligible cases, we conducted 
reviews for administrative coverage only for 268 cases, and for the remaining 162 
cases we conducted reviews for both administrative coverage and medical necessity.  
Reviewers followed a structured protocol that OIG developed in consultation with 
health care coding experts and physicians. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Background | 6  Administrative coverage reviews: Our health care coding experts determined 
whether the prior authorization or payment requests met the Medicare coverage rules 
and/or MAO billing rules that the MAO cited as support for its denial decision.  For 
example, MAOs often cited NCDs and LCDs; the Medicare Managed Care Manual; 
the beneficiarys Evidence of Coverage Document; and other MAO billing rules. 
Medical necessity reviews: If our health care coding experts assessed that denial 
cases needed a medical necessity review to determine whether the request met 
Medicare coverage rules, then the cases received an additional clinical review by a 
physician.  Following a structured OIG protocol, physicians used their clinical 
judgment to determine whether the denied service was medically necessary for the 
beneficiary using the medical records and other clinical information available in the 
case file.  For any case for which the physician reviewer determined that the service 
was medically necessary, or for which the physician reviewer wanted to consult with 
other physicians, we convened consensus calls among a panel of three physicians to 
discuss the case.  The three-physician panel then reached consensus regarding 
whether a denied service was medically necessary for the beneficiary, based on clinical 
information in the medical records that the MAO had submitted to OIG.  A health care 
coding expert then reviewed these cases to determine whether the case met 
administrative rules for Medicare coverage.   
Analysis 
We analyzed the results of the reviews by health care coding experts and the clinical 
reviews by physicians, and we generated population estimates of the rates of prior 
authorization denials and payment denials for requests that met Medicare coverage 
rules and MAO billing rules.  We also generated population estimates for the rates at 
which prior authorization denials and payment denials were issued for services that 
met Medicare coverage rules and MAO billing rules, but were then reversed by the 
MAOs.  See Appendix A on page 31 for point estimates, 95-percent confidence 
intervals, and key statistics.   
Limitations 
The results of the case reviews were limited to the documentation available in the 
medical records submitted by the MAOs at the time of our review.  Although we 
followed up with MAOs to help ensure that they submitted all relevant records, we 
were not able to verify whether additional information might have existed but was not 
submitted.  Further, the case review results were subject to the interpretations and 
clinical judgments of the health care coding experts and physician reviewers.   
Because a significant number of cases in the sample did not have cost data in their 
records, we were not able to estimate the costs associated with denials, such as added 
charges to Medicare beneficiaries or unpaid reimbursements to providers.  When this 
information was available, we indicated the cost associated with denials in our sample 
that we determined met Medicare coverage rules and MAO billing rules.   
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Background | 7  Standards 
We conducted this study in accordance with the Quality Standards for Inspection and 
Evaluation issued by the Council of the Inspectors General on Integrity and Efficiency.     
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Background | 8  FINDINGS 
Thirteen percent of prior authorization denials were for service 
requests that met Medicare coverage rules, likely preventing or 
delaying medically necessary care for Medicare Advantage 
beneficiaries 
Of the 12,273 denials of requests for services (prior authorization denials) issued by 
the 15 selected MAOs during the first week of June 2019, an estimated 13 percent 
met Medicare coverage rules.22  In other words, these services likely would have been 
approved for these beneficiaries under original Medicare (also known as Medicare 
fee-for-service).  This projects to 1,631 prior authorization denials for requests that 
met Medicare coverage rules for the selected MAOs during that week.  For an annual 
context, if these MAOs denied the same number of prior authorization requests 
(1,631) in each of the other 51 weeks of 2019, they would have denied 
84,812 beneficiary requests for services that met Medicare coverage rules that year. 
MAO denials of prior authorization requests for services that meet Medicare coverage 
rules can create significant negative effects for Medicare Advantage beneficiaries.  
These denials can delay or prevent beneficiary access to medically necessary care; 
lead beneficiaries to pay out of pocket for services that are covered by Medicare; or 
create an administrative burden for beneficiaries or their providers who choose to 
appeal the denial.  These denials may be particularly harmful for beneficiaries who 
cannot afford to pay for services directly and for critically ill beneficiaries who may 
suffer negative health consequences from delayed or denied care.   
MAOs denied prior authorization requests for services that were 
medically necessary by applying MAO clinical criteria that are not 
contained in Medicare coverage rules 
For many of the denials of prior authorization requests in our sample for services that 
met Medicare coverage rules, MAOs denied the requests by applying MAO clinical 
criteria that are not required by Medicare.  As shown in the examples below, we found 
that in these cases MAOs used specific, mandatory requirements that resulted in the 
denial of prior authorization requests for medically necessary services.  In contrast, 
original Medicare does not impose such specific requirements for covering the 
procedures involved.  (For more detailed descriptions of all prior authorization and 
 
22 As stated on page 4 of this report, in 2018, MAOs denied 5 percent of all prior authorization requests 
in the Medicare Advantage program. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 9  payment cases that met Medicare coverage rules and MAO billing rules, see 
Appendix B on page 32.) 
Case D472: MAO restricted followup MRIs based on the size of the 
beneficiarys lesion, a restriction that is not included in Medicare coverage 
rules. 
Eight months after a beneficiary was discovered to have an adrenal lesion of 1.5 cm in 
size, an MAO denied a request for a followup MRI (estimated cost $300).  The MAO 
stated that the beneficiary would need to wait at least 1 year for the followup MRI 
because the size of the lesion (less than 2 cm) was too small to warrant followup 
before 1 year.  However, our health care coding experts determined that the 
applicable NCD does not restrict the timing of followup MRIs based on the size of 
lesions.  Furthermore, our physician panel stated that the documentation in the 
original request demonstrated that the MRI was medically necessary to determine 
whether the lesion seen on an earlier CT scan was malignant.  (The MAO reversed its 
original denial upon appeal.  See case D472 in Appendix B for additional details.) 
 
Case D460: MAO applied an ambulatory device limit that is not included in 
Medicare coverage rules. 
An MAO denied a request for a walker (estimated cost $112) for a 76-year-old 
beneficiary with post-polio syndrome.  The MAO stated that, per its clinical criteria, 
the beneficiary was not eligible to receive a walker because the beneficiary had 
already received a cane within the past 5 years.  The MAOs clinical criteria considered 
these devices to be the same or similar and limited beneficiaries to one such device 
every 5 years.  However, our health care coding expert determined that the applicable 
LCD for walkers does not include a 5-year restriction on more than one ambulatory 
device.  Further, our physician panel determined that the walker was medically 
necessary given the beneficiarys history, risk of falling, and physical therapy notes.  
These factors indicated that the beneficiary could not walk safely with only a cane.  
(See case D460 in Appendix B for additional details.) 
CMS officials reported that MAOs may use internal clinical criteria that do not 
contradict Medicare coverage rules; however, existing guidance is not 
sufficiently detailed for OIG to determine whether CMS would consider each of 
these denials in our sample to be inappropriate 
In several cases, we were unable to determine whether the prior authorization denials 
that met Medicare coverage rules would be considered allowable by CMS because 
CMSs guidance regarding MAO use of internal clinical criteria is not sufficiently 
detailed.  The following example helps to illustrate the problem: An MAO denied a 
prior authorization request for a CT scan (case D479) that our physician reviewers 
determined was medically necessary.  The MAO stated that its clinical criteria required 
the beneficiary to have an x-ray first to prove that a more advanced imaging 
procedure (a CT scan) was needed.  However, the Medicare NCD for CT scans states: 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 10  [T]here is no general rule that requires other diagnostic tests to be tried before CT 
scanning is used."  This suggests thatall other things being equalMedicare would 
have paid for the CT scan for this beneficiary if the beneficiary were enrolled in 
original Medicare, whereas the service was denied for the beneficiary in Medicare 
Advantage.   
The section of the Medicare Managed Care Manual governing this issue states that 
MAO internal policies for medical necessity determinations must use coverage 
criteria no more restrictive than original Medicares national and local coverage 
policies.23  In the example above, because the Medicare coverage rule does not 
require a beneficiary to have an x-ray prior to a CT scan, and because the NCD states 
specifically that there is no such requirement in original Medicare, one could conclude 
that the MAO used criteria that were more restrictive than original Medicare.   
CMS officials reported to OIG that MAOs may establish additional clinical criteria for 
Medicare-covered services, as long as the criteria are evidence-based and do not 
contradict the applicable Medicare coverage rules.  Therefore, in the example above, 
the denial of prior authorization for the CT scan could be considered allowable if CMS 
judged that the MAOs x-ray requirement was evidence-based and did not contradict 
the Medicare NCD for CT scans.   
Given the current language in the Medicare Managed Care Manual, and because CMS 
has not issued guidance on what types of clinical criteria would be considered more 
restrictive than or contradictory to Medicare coverage rules, OIG was unable to 
determine whether certain denials of Medicare-covered services would be considered 
allowable by CMS. 
MAOs denied prior authorization requests for medically 
necessary services when providers did not respond to requests 
for unnecessary documentation 
In some prior authorization cases in our sample that met Medicare coverage rules, 
MAOs contacted providers to request unnecessary documentation (e.g., additional 
test results) before making their decision, and then denied the request when 
providers did not supply the additional documentation.  In some of these cases, the 
MAO reviewer requested additional documents to further support that the requested 
service was medically necessary; however, our physicians determined that the clinical 
information in the case file was already sufficient to demonstrate medical necessity.  
In other cases, the MAO reviewer asked for copies of documentation already 
contained in the case file.   
Case D199: MAO requested documentation that was already on file. 
An MAO denied a request for Botox medication for a beneficiary with a diagnosis of 
urge incontinence (estimated cost $3,674).  The MAO incorrectly stated that there was 
 
23 CMS, Medicare Managed Care Manual, ch. 4, sec. 10.16. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 11  a lack of clinical information about the beneficiarys previous use of the medication 
and asked for additional records.  However, the MAO had already received records 
documenting the beneficiarys previous use of Botox as part of the prior authorization 
request, making the request for the documentation unnecessary.  (The MAO noted 
that it reversed the denial after receiving OIGs data request.  See case D199 in 
Appendix B for additional details.) 
Eighteen percent of payment denials were for claims that met 
Medicare coverage rules and MAO billing rules, which delayed 
or prevented payments for services that providers had already 
delivered 
Of the 160,378 payment denials issued by the 15 selected MAOs during the first week 
of June 2019, an estimated 18 percent met Medicare coverage rules and MAO billing 
rules and should have been approved by the MAOs.24  This projects to 28,949 
payment denials that met Medicare coverage rules and MAO billing rules for the 
selected MAOs during that week.  For an annual context, if these MAOs denied the 
same number of payment requests (28,949) in each of the other 51 weeks of 2019, 
they would have denied 1.5 million payment requests that met Medicare coverage 
rules and MAO billing rules that year.  Denying payment requests that meet these 
rules delays or prevents providers from receiving payment for services that they have 
already delivered to beneficiaries, which can burden providers. 
MAOs denied payments to providers because of human error 
during manual reviews  
MAOs rely on their staff to manually review some requests for payments before 
approving or denying them.  However, these manual reviews are susceptible to 
human error, such as a reviewers overlooking a document in the case file or 
inaccurately interpreting CMS or MAO coverage rules.  These errors can result in 
denied payments to providers for services that meet Medicare coverage rules and 
MAO billing rules. 
 
24 As stated on page 4 of this report, in 2018, MAOs denied 9.5 percent of all payment requests in the 
Medicare Advantage program. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 12  Case D187: MAO reviewer was unfamiliar with network facility coverage 
rules. 
An MAO reviewer denied a payment request for care at a skilled nursing facility 
because it was delivered by a provider who was not contracted with the MAO 
(estimated cost $50).  In most cases, a beneficiary needs prior authorization to receive 
care from a noncontracted provider.  However, the skilled nursing facility was 
an in-network facility.  This qualified the claim as plan-directed care, and therefore 
no prior authorization was required.  The MAO attributed the denial to human error.  
(The MAO noted that it reversed the denial after receiving OIGs data request.  See 
case D187 in Appendix B for additional details.) 
 
Case D442: MAO reviewer did not account for documentation already on 
file. 
An MAO denied payment for radiation treatment for an elderly cancer patient with 
a tumor on the pancreas ($336).  The MAO incorrectly claimed that no prior 
authorization had been submitted for the service.  However, the provider 
subsequently submitted a screenshot demonstrating that the MAO had granted 
a prior authorization for the billed claim.  The MAO attributed this denial to human 
error and reversed the denial, noting that the MAOs reviewer did not see the prior 
authorization in the file.  (See case D442 in Appendix B for additional details.) 
MAOs denied payment requests because of inaccurate 
programming of claims processing systems  
When MAO systems for claims processing are programmed incorrectly, or are not 
updated timely, they can result in denials for payments that should be approved.  
Unlike errors generated on a case-by-case basis during a manual review, system 
errors can cause greater harm because they automatically generate a potentially 
larger volume of incorrect denials until the MAO notices the error and fixes it. 
Case D444: MAOs system failed to correctly route claims for manual review. 
One MAOs established procedure was to manually review payment requests from 
providers with multiple taxpayer identification numbers (TINs) so that the correct TIN 
could be chosen.  However, the system was programmed incorrectly and did not 
automatically route these cases for manual review.  In this case, an in-network 
provider submitted a claim for physical therapy services, but the MAOs system chose 
an incorrect TIN, making the provider appear to be out-of-network.  The MAO 
discovered the error after receiving OIGs data request and paid the claim ($108).  The 
MAO reported to OIG that the same error may have affected 163 additional provider 
payment requests and that it was working to implement an automated process to 
prevent a reoccurrence.  (See case D444 in Appendix B for additional details.) 
 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 13  Case D441: MAOs system did not recognize the authorized timeframe for a 
service. 
An MAO denied a request for radiation therapy ($668) for a 74-year-old beneficiary 
with prostate cancer, incorrectly stating that no prior authorization was on file for the 
date of service.  The provider disputed the denial and submitted a screenshot 
demonstrating that prior authorization had previously been obtained.  The MAO 
stated that its system had not correctly recognized the timeframe that had been 
authorized under the approved prior authorization request.  The MAO reversed the 
denial and reported that it updated its system to correct the error.  (See case D441 in 
Appendix B for additional details.) 
Imaging services, stays in post-acute facilities, and injections 
were three prominent service types among the denials that met 
Medicare coverage rules  
Among the denied requests for prior authorizations and payments that met Medicare 
coverage rules and MAO billing rules that we identified in our sample, there was 
a wide range of service types.  Three of the most prominent service types were 
advanced imaging services (including MRIs and CT scans); post-acute care in skilled 
nursing facilities and inpatient rehabilitation facilities (i.e., care after hospital stays); 
and injections.25  To reduce their costs, MAOs may have an incentive to deny more 
expensive services, such as inpatient rehabilitation facility stays, and/or require that 
beneficiaries receive less expensive alternatives.  We also observed denials that met 
Medicare coverage rules and MAO billing rules for items or procedures that may 
receive extra scrutiny from MAOs because they can be vulnerable to fraud, such as 
durable medical equipment and injections for pain management.26 
MAOs denied requests for advanced diagnostic imaging that met 
Medicare coverage rules and MAO billing rules, often stating that 
a more basic imaging service must be performed first 
Imaging services were the most common health care service type among the denials 
that met Medicare coverage rules and MAO billing rules in our sample, and consisted 
mainly of advanced diagnostic imaging services, such as MRIs and CT scans.  
Medicare coverage rules state that MRIs and CT scans are covered when medically 
 
25 We also observed denials for physician services, durable medical equipment, surgery, inpatient hospital 
stays, ambulance transport, lab tests, therapy, radiation treatment, chiropractic services, and other tests.  
See Appendix B for more detail on the denial cases in our sample that met Medicare coverage rules.  
26 Durable medical equipment and injections for pain management have been the subject of many 
prosecutions for health care fraud.  See, for example: Department of Justice, CEO Sentenced to Prison in 
$150 Million Health Care Fraud, Opioid Distribution, and Money Laundering Scheme.  Accessed on 
March 21, 2022. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 14  necessary and appropriate for the beneficiary.27  Medicare does not have a blanket 
requirement that beneficiaries receive specific tests or treatments prior to receiving an 
MRI or CT scan.28  However, in several cases MAOs denied requests for advanced 
diagnostic imaging that our physician panel determined were medically necessary, 
and that health care coding experts determined met Medicare coverage rules, 
because the beneficiary had not first received a more basic imaging service or more 
conservative treatment.  As discussed earlier in this report, MAOs often cited MAO 
clinical criteria not contained in Medicare coverage rules to justify these denials of 
imaging services.   
Case D221: MAO required an x-ray before it would approve an MRI. 
An MAO denied a request for an MRI (estimated cost $365) of the hand for 
a Medicare beneficiary who continued to have pain and weakness in the hand  
5 months after a fall.  The MAO cited its clinical criteria that required, among other 
things, that the beneficiary undergo an x-ray that then failed to provide a diagnosis 
before the MAO would authorize an MRI.  However, our reviewers determined that 
the MRI was medically necessary and reasonable for the beneficiary and the 
applicable Medicare NCD does not have a requirement that a beneficiary receive an x-
ray prior to an MRI.  Further, our physician panel explained that an x-ray would not be 
sufficient for this patient because some hand injuriessuch as those involving small 
bones, muscles, and ligaments in the handmay not be visible with an x-ray.  The 
physician panel also noted that delayed treatment could cause further harm for this 
beneficiary because the muscles and ligaments might retract.  The MAO reversed the 
prior authorization denial upon appeal.  (See case D221 in Appendix B for additional 
details.) 
 
Case D406: MAO required provider-directed treatment before it would 
approve an MRI. 
An MAO denied a request for an MRI (estimated cost $297) for a 91-year-old 
beneficiary with worsening chronic low back pain with sciatica (pain that radiates from 
the lower back through the hips and down the leg).  The MAOs medical director 
denied the request because the beneficiary had not completed 6 weeks of 
provider-directed treatment within the preceding 3 months.  However, our physician 
panel determined that the beneficiary needed the MRI because of the beneficiarys 
age, the diagnosis, and the results of a previous back x-ray.  Further, the NCD for MRIs 
does not require that beneficiaries complete 6 weeks of provider-directed treatment 
before receiving an MRI.  (See case D406 in Appendix B for additional details.) 
 
27 CMS, National Coverage Determination (NCD) for Computed Tomography (220.1), March 12, 2008.  
CMS, National Coverage Determination (NCD) for Magnetic Resonance Imaging (220.2), April 10, 2018. 
28 In individual cases, the use of an MRI or CT scan as the initial diagnostic test may not be reasonable 
and necessary because it is not supported by the beneficiarys symptoms (and it would then be 
appropriate to deny the request for the advanced imaging and suggest more conservative treatment 
first).   
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 15  MAOs denied requests for transfers to post-acute care facilities 
that met Medicare coverage rules, claiming that beneficiaries 
needs could be met at a lower, less costly level of care 
Among the denial cases that met Medicare coverage rules in our sample, several were 
prior authorization requests to discharge patients from the hospital to inpatient 
rehabilitation facilities or to skilled nursing facilities.  In their justifications for these 
denials, MAOs often claimed that the patients did not need intensive therapy or 
skilled care, and that their needs could be met at a lower level of care, such as home 
health services at the patients residence.  However, our physician panel determined in 
these cases that the patients met the clinical criteria for admission to the relevant 
facilities, that they would have benefited from the higher level of care  ordered by the 
requesting physician, and that the alternatives offered by the MAOs were not clinically 
sufficient to meet the patients needs.   
Post-acute services provided in facilities for rehabilitation and skilled nursing care are 
significantly more expensive than home health services, which may lead to increased 
scrutiny from MAOs for these types of requests.  (See Exhibit 2.) 
Exhibit 2: Costs for post-acute care can vary widely across different settings     
Inpatient rehabilitation facilities provide intensive therapy and medical services in 
a hospital environment to patients with complex nursing, medical management, and 
rehabilitative needs.   
Average payment per stay in 2018 under original Medicare: $20,124. 
 
Skilled nursing facilities provide skilled nursing or therapy services to patients for 
rehabilitation following inpatient hospital stays.   
Average payment per stay in 2018 under original Medicare: $11,592. 
 
Home health services include intermittent skilled nursing care, physical therapy, or 
speech-language pathology, and continuing occupational therapy services for 
patients who are unable to leave home or can leave home only with considerable 
effort.   
Average payment per stay in 2018 under original Medicare: $3,089. 
Sources: CMS, Inpatient Rehabilitation Therapy Services: Complying with Documentation Requirements, Medicare 
Coverage of Skilled Nursing Facility care, and Medicare Home Health Benefit Booklet.  Information on costs from: 
Medicare Payment Advisory Commission, A Data Book: Health Care Spending and the Medicare Program, July 2020. 
Skilled nursing facility costs calculated using the number of Medicare skilled nursing facility stays and total 
Medicare skilled nursing facility payments. 
Case D260: MAO offered an insufficient alternative level of care. 
An MAO denied a request to transfer a beneficiary from the hospital to a skilled 
nursing facility, stating that a lower level of care (home health services) could meet 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 16  the beneficiarys medical needs.  The beneficiary had pain and swelling from cellulitis 
(a bacterial skin infection) and bedsores.  The patient was unable to carry out activities 
of daily living, could stand for only a few minutes at a time, and was no longer able to 
walk with the help of a rolling walker.  Our physician panel determined that, 
considering the beneficiarys deteriorating functional status, comorbidities, and need 
for daily skilled care, the patient met Medicare coverage requirements for skilled 
nursing facility care outlined in the Medicare Benefit Policy Manual and would benefit 
from occupational and physical therapy.  The MAO reversed this denial upon appeal.  
(See case D260 in Appendix B for additional details.) 
 
Case D278: MAO denied care that met patients needs. 
An MAO denied a request for a referral to an inpatient rehabilitation facility for a 
beneficiary with a fractured femur who was recovering from screw placement surgery.  
The MAO stated that the beneficiary did not meet all medical necessity criteria for 
admission to an inpatient rehabilitation facility, and that the beneficiarys needs could 
be met in other, lower-level-of-care settings, such as a skilled nursing facility, home 
with home health services, or home with outpatient therapy.  However, our physician 
panel determined that the beneficiary met the medical necessity criteria for an 
inpatient rehabilitation facility stay as outlined in the Medicare Benefit Policy Manual, 
including the need to be examined by a rehabilitation physician at least 3 days per 
week.  The physician reviewer added that a lower level of care was not a clinically 
sufficient alternative because the beneficiary would not have access to physician 
supervision to facilitate recovery from pneumonia and other post-operative risks.  
(See case D278 in Appendix B for additional details.) 
MAOs denied requests for injections, in some cases by 
misapplying Medicare coverage rules 
A third prominent service type among the denials that met Medicare coverage rules 
in our sample was injections.  Some of these injections were for pain management, 
which have been subject to improper billing and fraud in Medicare, and so may 
receive extra scrutiny from MAOs.  However, in two of the pain-management injection 
cases in our sample, case reviews determined that MAO reviewers misapplied 
Medicare coverage rules (see examples below).   
Case D401: MAO misapplied Medicare coverage rules. 
An MAO denied a request for an injection to alleviate severe and worsening neck pain 
for a 72-year-old beneficiary.  The request was for an injection in the cervical 1-2 joint 
between the first and second vertebrae at the top of the spine (estimated cost $238).  
The MAO stated that the LCD allowed for that type of injection only for lower areas of 
the spine.  However, our physician panel determined that the injections were 
medically necessary given the beneficiarys chronic, continuous pain, and our health 
care coding expert determined that the LCD referenced by the MAO did not preclude 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 17  the use of injections in the cervical 1-2 joint.  (See case D401 in Appendix B for 
additional details.) 
 
Case D475: MAO misstated Medicare coverage utilization limits. 
An MAO denied a request for facet joint injections in three sections of the spine 
(estimated cost $95), incorrectly stating that the number of injections requested 
exceeded the Medicare coverage limit of: (1) one to two injections per section of the 
spine per session, or (2) up to five injection sessions in a 12-month period.  Our 
physician panel determined that the injections were medically necessary and 
reasonable because the beneficiary, who had degenerative osteoarthritis of the spine 
and a history of neck, low back, and hip pain, had reported significant relief from two 
prior injection sessions.  Further, our health care coding expert determined that the 
LCD that the MAO cited does not include a limit on the number of injections per 
section of the spine per session, and that the requested session would not cause the 
beneficiary to exceed five sessions in a 12-month period.  (See case D475 in Appendix 
B for additional details.) 
MAOs reversed some initial prior authorization denials and 
payment denials for requests that met Medicare coverage rules 
and MAO billing rules  
For 3 percent of prior authorization denial cases, and 6 percent of payment denial 
cases, MAOs initially denied requests that met Medicare coverage rules, and then 
reversed their decisions before our data request (within 3 months of the original 
denial).29  Although reversed denials for prior authorization requests mean that 
beneficiaries ultimately were offered coverage for needed care, the process also can 
create a burden for beneficiaries who need to navigate the appeals process.  Similarly, 
reversed denials for payment requests mean that providers were ultimately paid for 
the services that they delivered.  However, each denial for a payment request that met 
Medicare coverage rules and MAO billing rules represents a case in which providers 
were delayed payment and/or had to dispute a denial that ideally would have been 
approved upon the first request.  These avoidable delays and extra steps create 
friction in the program and may create an administrative burden for beneficiaries, 
providers, and MAOs.   
 
 
29 We requested case file documentation in September 2019, 3 months after MAOs issued the initial 
denials.  In a small number of cases, MAOs discovered errors while preparing cases files for our data 
request and notified OIG that they reversed the denials.  Because we do not know if these reversals 
would have occurred in the absence of our data request, we did not include them in our estimates. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 18  MAOs reversed some denials for prior authorization requests 
following beneficiary appeals 
For 3 percent of prior authorization denials, MAOs initially denied requests that met 
Medicare coverage rules, and later reversed these denials within 3 months and 
approved the requests.  Most of these reversals occurred because beneficiaries or 
their providers filed appeals.  Among the denials for prior authorization requests in 
our sample that met Medicare coverage rules and that were appealed, MAOs reversed 
all of the denials and authorized all of the requested services.    
Case D421: MAO delayed a CT scan by 5 weeks for a beneficiary with cancer. 
An MAO denied a request for a CT scan of the chest and pelvis for a beneficiary with 
endometrial cancer.  The provider was able to get the denial reversed 5 weeks after 
the initial request by submitting additional information and filing an appeal.  
However, our physician panel determined that the original request had sufficient 
documentation to demonstrate that the CT was needed to assess the stage of the 
cancer and to determine the appropriate course of treatment.  Delayed care can 
negatively affect beneficiary health, particularly for urgent conditions.  Our physician 
reviewer noted the importance of timely monitoring the growth and extent of cancer 
to assess severity of the disease and determine the course of treatment.  (See case 
D421 in Appendix B for additional details.) 
MAOs reversed some payment denials following provider 
disputes 
For 6 percent of payment denials, MAOs initially denied payment requests that met 
Medicare coverage rules and MAO billing rules, and later reversed these denials 
within 3 months and paid the claims.  In some cases, providers presented evidence in 
their dispute that the MAO should have approved payment, such as screenshots that 
the MAO had previously approved a prior authorization for the service that had been 
provided.  (See cases D073, D119, and D441 in Appendix B.)  In other cases, the 
providers dispute prompted the MAO to acknowledge system or manual errors that 
resulted in payment denials, such as incorrect configuration of provider coverage 
details.  (See case D116 in Appendix B.)  
Case D489: MAO acknowledged that prior authorization was not required 
after the provider disputed the denial. 
An MAO denied payment for x-ray services for a patient with osteoarthritis, incorrectly 
stating that prior authorization was required for the x-rays.  The provider disputed the 
denial and included screenshots of an email exchange with a plan representative who 
confirmed that prior authorization was not needed.  On reviewing the dispute, the 
MAO acknowledged its error and reversed the denial, and then paid the claim ($102).  
(See case D489 in Appendix B for additional details.) 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About  
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Findings | 19  CONCLUSION AND RECOMMENDATIONS  
As Medicare Advantage enrollment continues to grow, MAOs play an increasingly 
critical role in ensuring that Medicare beneficiaries have access to medically necessary 
covered services and that providers are reimbursed appropriately.  MAOs are 
expected both to ensure access to high-quality care and to implement critical 
program controls in order to avoid unnecessary costs and ensure program integrity.  
However, capitated payment models, such as Medicare Advantage, can create an 
incentive for MAOs to deny the prior authorization of services for beneficiaries, and 
payments to providers, including some services and payment that would not have 
been denied in original Medicare.  Denied requests that meet Medicare coverage 
rules may prevent or delay beneficiaries from receiving medically necessary care and 
can burden providers.  Even when denials are reversed, avoidable delays and extra 
steps create friction in the program and may create an administrative burden for 
beneficiaries, providers, and MAOs.  Further, beneficiaries enrolled in Medicare 
Advantage may not be aware that there may be greater barriers to accessing certain 
types of health care services in Medicare Advantage than in original Medicare.   
Our findings about the circumstances under which MAOs denied requests that met 
Medicare coverage rules and MAO billing rules provide an opportunity for 
improvement to ensure that beneficiaries enrolled in Medicare Advantage have timely 
access to all necessary health care services, and that providers are paid appropriately.  
In some cases, the MAOs identified their own errors and reversed the denials, in 
others, MAOs reversed denials following appeals.  This suggests that improvement 
efforts by MAOs could reduce the number of similar errors in the future.  The causes 
of other cases of denied prior authorization and payments for services that met 
Medicare coverage rules and MAO billing rules warrant further action by CMS, 
including guidance to MAOs and CMSs oversight audits.     
Therefore, we recommend that CMS:   
Issue new guidance on the appropriate use of MAO clinical 
criteria in medical necessity reviews 
To help ensure that Medicare Advantage enrollees receive all medically necessary and 
covered services, to help promote MAO compliance with Medicare coverage rules, 
and to help improve program transparency, CMS should issue new guidance on both 
the appropriate use and the inappropriate use of MAO clinical criteria that are not 
contained in Medicare coverage rules.  The guidance should clarify what the Medicare 
Managed Care Manual means when it says that MAO clinical criteria must not be 
more restrictive than Medicare coverage rules, and it should include specific 
examples of criteria that would be considered allowable and unallowable.  CMS 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise  
Concerns About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Conclusion and Recommendations | 20  should also instruct MAOs to examine and revise their procedures for making 
coverage determinations, as needed, considering CMSs new guidance.   
Update its audit protocols to address the issues identified in this 
report, such as MAO use of clinical criteria, and/or examine 
particular service types  
CMS should update its audit protocols to look for issues identified in this report.  
Although CMSs audit protocols already direct auditors to review a sample of denial 
cases to determine whether the denials were issued appropriately, CMS should add 
additional prompts for auditors.  For example, following the publication of the new 
guidance relating to the use of clinical criteria in medical necessity reviews, CMS could 
add questions for auditors in section 3.2 of its audit protocol (Clinical Appropriateness 
of Denials) to determine whether MAOs are following the new guidance.  Similarly, 
CMS could add a question for auditors examining whether MAOs requested 
unnecessary documentation.   
If MAOs are found to be noncompliant because they are using more restrictive clinical 
criteria or requesting unnecessary documentation, CMS should follow its normal 
enforcement action process, including adding aggravating factors in civil money 
penalty calculations if MAO denials resulted in beneficiaries not being able to access 
needed services.  Further, CMS should consider additional enforcement actions for 
MAOs that demonstrate a pattern of inappropriate payment denials.  
CMS also should consider targeting in its audits specific service types that have a 
history of inappropriate denials, which could include the service types identified in 
this report.  CMS could choose to focus on service types for which inappropriate 
denials may have a significant impact on beneficiary health and well-being, such as 
stays in post-acute facilities.  Selecting a targeted sample may increase the likelihood 
of finding inappropriate denials. 
Direct MAOs to take additional steps to identify and address 
vulnerabilities that can lead to manual review errors and system 
errors  
Although some of the denials discussed in this report were attributable to one-off 
human errors, others seemed preventable through process or system changes by 
MAOs.  CMS should direct MAOs to examine their processes for manual review and 
system programming and remediate vulnerabilities that may result in inappropriate 
denials.  For example, CMS could point to this report, including the detailed 
explanations of the errors in Appendix B, to help MAOs identify the types of errors 
that they should be looking for.  To help avoid system errors, CMS could direct MAOs 
to take additional steps to ensure that any changes affecting coverage or payment 
(especially those on an established schedule, such as renewal of a providers contract 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise  
Concerns About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Conclusion and Recommendations | 21  with the MAO), are properly coded in their systems.  CMS could also direct MAOs to 
consider additional staff training on documentation that should be verified before 
issuing a denial, and the level of documentation required.   
 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise  
Concerns About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Conclusion and Recommendations | 22  AGENCY COMMENTS AND OIG RESPONSE 
In response to the draft report, CMS stated that it is committed to oversight and 
enforcement of the requirements of the Medicare Advantage program and concurred 
with all three recommendations.  CMS reiterated that MAOs must follow Medicare 
coverage rules.  CMS further stated that MAOs may implement additional coverage 
requirements to better define the need for a service as long as the additional 
requirements do not violate the requirements in the relevant NCD or LCD.  However, 
as we note in our report, this statement is not clearly outlined in existing guidelines.   
CMS concurred with the first recommendation to issue new guidance on the 
appropriate use of MAO clinical criteria for medical necessity reviews, stating that it 
plans to issue such guidance.   
CMS concurred with the second recommendation to update its audit protocols to 
address the issues identified in this report, such as MAO use of clinical criteria and/or 
examining particular service types.  CMS stated that it will update its audit protocol 
and auditor training materials, as needed, to align with the guidance that it plans to 
issue under the first recommendation.  CMS did not indicate whether it would 
consider targeting in its audits specific service types that have a history of 
inappropriate denials.   
CMS concurred with the third recommendation to direct MAOs to take additional 
steps to identify and address vulnerabilities that can lead to manual review errors and 
system errors.  CMS stated that it would direct MAOs to examine their manual review 
and system programming processes and to address vulnerabilities that may result in 
inappropriate denials.  Although CMS stated that these efforts would be in keeping 
with the guidance that it plans to issue in response to the first recommendation, OIG 
notes that the manual review errors and system processing errors identified in this 
report were unrelated to reviews for medical necessity.  
For the full text of CMSs comments, see Appendix D. 
 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise  
Concerns About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Agency Comments and OIG Response | 23  DETAILED METHODOLOGY 
Sample selection 
MAO selection.  To select the MAOs for this review, we used CMS Part C enrollment 
data to identify the number of beneficiaries in health maintenance organization 
(HMO) plans and preferred provider organization (PPO) plans administered by each 
MAO in June 2019.  We selected 15 of the largest MAOs by enrollment.  The  
15 selected MAOs accounted for nearly 80 percent of beneficiaries enrolled in 
Medicare Advantage in June 2019, ranging in size from about 165,000 to nearly 
6 million beneficiaries.   
Case selection.  We collected a list of all prior authorization denials and payment 
denials that each selected MAO issued during a 1-week period, June 17, 2019 
(282,830 total denials).  We created a sampling frame from this list by grouping 
denials into 7 strata based on denial type (prior authorization or payment) and the 
number of denials issued by the MAO during that week.  From this sampling frame, 
we selected a stratified random sample of 500 cases (250 prior authorization denials 
and 250 payment denials).  
We stratified by denial type in order to make projections of the rates of prior 
authorization denials and payment denials that were issued for requests that met 
Medicare coverage rules and MAO billing rules.  We also stratified by MAO size.  We 
under-sampled MAOs with larger numbers of denials to avoid over-burdening them 
with a high number of requests for case file documentation.  See Exhibit 3 on page 26 
for a description of each stratum, sample size, and population of denial cases. 
Excluding ineligible cases.  We instructed MAOs to exclude certain denials, such as 
those for supplemental services and claims with third-party liability, from the lists of 
prior authorization denials and payment denials that they submitted.  During the 
course of our review, we identified and excluded additional types of ineligible cases 
from our analysis.   
We identified 70 ineligible cases in our original sample of 500 cases, making our final 
sample 430 cases (183 payment and 247 prior authorization cases).  Types of denials 
that were ineligible for this review included: 
  Services already paid for under another payment arrangement: In some cases, 
MAOs pay providers under a capitated arrangement.  Providers may bill the 
MAO to document a service/encounter with the beneficiary, and these bills 
can create the appearance of a denial, but providers do not expect 
reimbursement for the specific services in addition to the capitated payment 
that they are already receiving.  These cases were ineligible for this study 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns  
About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Detailed Methodology | 24  because the MAO did not make a coverage decision based on the merits of 
the case, and there was no expectation of payment to the provider. 
  Cases denied because of a GY modifier: In some cases, providers may bill for a 
service that they know will not be covered (for example, to get a record of a 
Medicare denial before billing secondary insurance).  They may attach a GY 
modifier to the HCPCS (Healthcare Common Procedure Coding System) code 
on the claim, which signals that the claim should not be paid.  These cases 
were ineligible for this study because providers were not requesting payment.  
  Exact duplicates: In some cases, system or human errors may cause the same 
claim to be submitted from a provider to the MAO more than once.  Cases 
that were denied as exact duplicates were ineligible for this study because 
they were not denials based on the merits of the case.  
  Services paid by Medicaid for beneficiaries dually eligible for Medicare and 
Medicaid: Some beneficiaries who are dually eligible for both Medicare and 
Medicaid are enrolled in special plans through which a single MAO 
administers both their Medicare and Medicaid benefits.  Some of these MAO 
systems are set up to process requests for certain services as Medicare 
denials before they will approve and pay for them under the beneficiarys 
Medicaid benefit.  These cases were ineligible for this study because they 
were not true denials based on the merits of the case, but rather a system 
processing step. 
  Supplemental services: MAOs are allowed to cover extra health and wellness 
services that are not normally covered under Medicare, such as gym 
memberships.  These supplemental services are not covered by all MAOs.  
These cases were ineligible for this study because the services would not be 
covered by original Medicare, and the cases would have had different 
coverage rules depending on the MAO.    
 
 
 
   
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns  
About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Detailed Methodology | 25  Exhibit 3: Total and Eligible Denial Sample Sizes and Populations, by Stratum 
Estimate of 
population of 
  Total sample  Population of  Eligible  eligible 
Stratum   Case type  MAOs  size  denials   sample size  denials  
Prior  Two largest MAOs by 
1  authorization  volume of denials for  50  5,177  50  5,177 
  prior authorization 
Four medium-sized 
Prior  MAOs by volume of 
2  80  4,761  77  4,582 
authorization  denials for prior 
authorization 
Nine smallest MAOs by 
Prior 
3  volume of denials for  120  2,514  120  2,514 
authorization 
prior authorization 
  Total prior authorization cases  250  12,452  247  12,273 
Largest MAO by 
4  Payment   volume for payment  70  150,405  31  66,608 
denials 
Six medium-sized 
5  Payment   MAOs by volume for  85  100,402  64  75,597 
payment denials 
Three small MAOs by 
6  Payment   volume for payment  45  12,570  42  11,732 
denials 
Remaining five MAOs 
with the smallest 
7  Payment   50  7,001  46  6,441 
volume for payment 
denials 
  Total payment cases  250  270,378  183  160,378 
Total cases    500  282,830  430  172,651 
Case File Collection and Preliminary Screening 
For the original 500 sampled cases, we collected case file documentation in 
September 2019 (3 months after the denials were originally issued).  We requested 
complete administrative and medical records from the MAOs.  Among other 
information, we requested that the MAOs provide a summary of the basic facts of the 
case, an explanation of their reason for denying the request, any coverage rules that 
MAOs cited to deny the request, records of the MAO decision-making process, copies 
of notices sent to the beneficiary and/or provider, any medical records on file, and 
whether the denial had been appealed.   
To conduct the case file reviews, we contracted with health care coding and billing 
professionals with expertise in Medicare coverage rules (health care coding experts) 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns  
About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Detailed Methodology | 26  and with physicians.  Health care coding experts used an OIG-developed protocol to 
complete a preliminary screening for all 500 cases in our sample.  The first step of the 
preliminary screening process was to determine whether the denial case was eligible 
for our sample (as described above).  The health care coding experts then reviewed 
the case files of the 430 eligible cases for completeness and made additional requests 
to the MAOs for missing records or information needed for case file reviews.   
Case File Reviews 
To design the case file review methodology, we consulted with the following: CMS; 
the Medicare Advantage Independent Review Entity contractor (which reviews denial 
appeals that are upheld by MAOs); physicians; and health care coding experts.  We 
also reviewed CMS policy documents such as the Medicare Managed Care Manual.   
The objective of the case file reviews was to determine whether the denied prior 
authorization and payment requests met relevant Medicare coverage rules and, if 
applicable, MAO billing rules.  For our sample of 430 eligible cases, we conducted 
reviews for administrative coverage only for 268 cases, and for the remaining 162 
cases we conducted reviews for both administrative coverage and medical necessity.  
Reviewers followed a structured protocol that OIG developed in consultation with 
health care coding experts and physicians. 
Administrative coverage reviews.  For denial cases that did not need a clinical 
review to determine medical necessity, a health care coding expert followed a 
structured OIG protocol to determine whether the denial met the Medicare coverage 
rules and/or MAO billing rules that the MAO cited as support for its denial decision.  
Examples of cases that did not need a medical necessity determination included 
denials that were issued because the beneficiary was no longer enrolled with the 
MAO; claims that were filed past required deadlines; claims for services that require 
prior authorization but for which the MAO did not have an authorization on file; and 
other administrative or billing inaccuracies.  Health care coding experts reviewed the 
MAOs justification for issuing the denial and determined whether the request met 
applicable Medicare coverage rules and MAO billing rules, such as NCDs and LCDs; 
the Medicare Managed Care Manual; and the providers contract.  They also examined 
MAO coverage documents (i.e., the Evidence of Coverage document for the 
beneficiarys plan), and any other documentation in the case file that supported or 
disputed whether the request met Medicare coverage rules and MAO billing rules. 
Medical necessity reviews.  If the health care coding experts assessed that denial 
cases needed a medical necessity review to determine whether the request met 
Medicare coverage rules, then the cases received an additional clinical review by a 
physician.  We assigned a physician reviewer to each of these cases on the basis of 
the service type and the physicians specialty.  Following a structured OIG protocol, 
physicians used their clinical judgment to determine whether the denied service was 
medically necessary for the beneficiary using the medical records and other clinical 
information available in the case file.  Physicians considered factors such as a 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns  
About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Detailed Methodology | 27  beneficiarys symptoms, diagnosis, and medical history to determine medical 
necessity and explain how they arrived at their decision.  Physicians also determined 
whether the MAO offered an alternate service to the beneficiary and if so, whether the 
alternate service was clinically sufficient to meet the beneficiarys needs.   
For cases in which the physician reviewer indicated that the service was not medically 
necessary for the beneficiary, OIG determined the denial to be appropriate because 
Medicare does not pay for services that are not medically necessary.  For any case for 
which the physician reviewer determined the service was medically necessary, or for 
which the physician reviewer wanted to consult with other physicians, we convened a 
panel of three physicians to discuss the case (see more on physician conference calls, 
below).  Services were determined to be medically necessary if the three-physician 
panel reached consensus that the requested service was medically necessary for the 
beneficiary. 
For denied requests that the physician panel determined were medically necessary, a 
health care coding expert reviewed the case to determine whether the request met 
Medicare coverage rules.  To do this, the health care coding expert reviewed the 
circumstances of the case, including the specific justification(s) that the MAO cited to 
deny the service and the panels explanation for why the service was medically 
necessary.  The health care coding expert then assessedconferring with the 
physician reviewer as neededwhether the request met applicable Medicare 
coverage rules and/or criteria from the MAO Evidence of Coverage document.  
Quality Assurance 
To promote consistency and accuracy across reviews, we issued a study-specific 
guidance document for improved decision-making, provided training to all physicians 
and health care coding experts, facilitated conference calls with the panel of physician 
reviewers, and conducted quality assurance reviews.  
Guidance Document.  We worked with the health care coding experts and physician 
reviewers to develop a structured protocol to ensure thorough and consistent case 
reviews.  We provided reviewers with a guidance document that included detailed 
instructions for each question in the health care coding and physician protocols, 
definitions for key terms, and a list of frequently asked questions.  The guidance 
included detailed instructions for determining whether a case was eligible for the 
study, which types of cases should be referred for physician review, and how to 
determine whether a denial met Medicare coverage and/or MAO billing rules.   
Training.  We provided two trainings for each reviewer type (i.e., health care coding 
experts and physicians) regarding the OIG protocol for reviewing the denial cases.  
The trainings included a review of the guidance document and an explanation of the 
protocol questions.  We also conducted pre-test reviews with some reviewers to pilot 
the protocols and give feedback to reviewers.  
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns  
About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Detailed Methodology | 28  Physician Consensus Calls.  We facilitated regular conference calls for physician 
reviewers to examine the medical necessity of individual cases and to promote 
consistency across reviews.  During these calls, physician reviewers discussed cases 
that a physician reviewer assessed to be medically necessary or wanted to discuss 
with the rest of the physician panel.  Denial cases were determined to be medically 
necessary if the physician reviewer and the physician panel reached consensus that 
the case was medically necessary.  
Quality Assurance Reviews.  We reviewed health care coding expert and physician 
protocol responses to ensure that they were following the standardized review 
protocols when assessing cases.  We worked with the medical review contractor to 
identify and address any inconsistencies across health care coding and physician 
clinical reviews.  Separately, we worked with health care coding experts and physicians 
to clarify or discuss any questions we had about their protocol responses.  We also 
had a health care coding expert conduct independent second reviews for a portion of 
denial cases.  Finally, we reviewed each case using the original case file and additional 
information we collected from MAOs to ensure: (1) that it was eligible to be included 
in our sample and (2) that protocol responses accurately reflected the circumstances 
of the case. 
Analysis 
We analyzed the results of the reviews by health care coding experts and the clinical 
reviews by physicians, and we generated population estimates of the prior 
authorization denials and payment denials that met Medicare coverage rules and 
MAO billing rules.  We also generated population estimates for the rates at which 
MAOs initially denied prior authorization denials and payment denials in our sample 
that met Medicare coverage rules and MAO billing rules, but then reversed their 
decision before our data request (within 3 months).  See Appendix A on page 31 for 
point estimates, 95-percent confidence intervals, and key statistics. 
To examine the reasons that denials occurred for requests that met Medicare 
coverage rules and MAO billing rules, and the service types associated with those 
cases in our sample, we conducted qualitative analysis of the case files and case 
review results.  We coded each denial that met Medicare coverage rules as resulting 
from one or more of six causes that surfaced from the reviewed cases.  To determine 
the cause of denials for requests that met Medicare coverage rules, we examined the 
MAOs justification for the denial, the results of the health care coding expert reviews 
and/or physician clinical reviews, and relevant documentation in the case files.  In 
some cases, we determined that the denials resulted from more than one cause, for 
example, when an MAO applied MAO clinical criteria not in Medicare coverage rules 
and required unnecessary documentation.  To describe service types, we categorized 
items or services using information from the case files.  Because of the small number 
of denials within each stratum that met Medicare coverage rules, it was not possible 
to project the results of the denial causes and service type categories. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns  
About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Detailed Methodology | 29  To provide cost information for the denials in our sample that met Medicare coverage 
rules, we reviewed case files to determine if cost information was available.  If 
available, we included this information in Appendix B and in some of the case 
examples presented in the report.  For cases where the MAO reversed the denial and 
documented paying for the service, we used the actual amount paid to the provider.  
For all other cases, we used the actual or estimated cost of the denied service as 
reported by the MAO.  Because a significant number of cases in the sample did not 
have cost data in their records, we were not able to estimate the overall costs 
associated with denials that met Medicare coverage rules.  
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns  
About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Detailed Methodology | 30  APPENDIX A 
Point Estimates and Confidence Intervals for Denials of Prior 
Authorization and Payment Requests That Met Medicare 
Coverage Rules, Issued by 15 Selected MAOs During June 17, 
2019 
95-Percent Confidence
Interval 
Weighted 
Description  Frequency  Percentage  Lower Bound  Upper Bound 
Denials of prior authorization  1,631  13.3%  8.9%  19.3% 
requests that met Medicare 
coverage rules 
Denials of prior authorization  343    2.8% 1.4%  5.7% 
requests that met Medicare 
coverage rules and were reversed 
within 3 months 
Denials of payment requests that  28,949       18.1%  11.7%  26.8% 
met Medicare coverage rules 
Denials of payment requests that  10,140      6.3%   3.0%  12.9% 
met Medicare coverage rules and 
were reversed within 3 months 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About 
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Appendix A | 31  APPENDIX B 
Detailed Descriptions of Denials for Requests That Met Medicare Coverage Rules 
Prior Authorization Denials of Requests That Met Medicare Coverage Rules 
Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D221  Imaging: MRI of  A 69-year-old  Applied MAO  The MAO denied the request and cited internal clinical criteria  Denial  $365 
right hand  continued to have  clinical criteria  requiring an inconclusive x-ray and documentation that the patient  reversed upon 
without contrast  pain and  not in  had not improved with more conservative treatment.  However,  appeal 
weakness in  Medicare  our reviewers determined that an MRI was necessary for this 
a hand 5 months  coverage rules  patient and the NCD for MRIs does not require that a beneficiary 
after a fall.  receive an x-ray prior to receiving an MRI.  Our physician panel 
Required  explained that an x-ray would not be sufficient for this patient 
unnecessary  because some hand injuries, such as those involving small bones, 
documentation  muscles, and ligaments in the hand, may not be immediately 
visible with an x-ray.  The panel noted that delayed treatment 
could cause further harm for this patient because the muscles and 
ligaments might retract.  
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 32  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D249  Imaging: Chest  A 68-year-old  Required  The MAO requested unnecessary additional medical records to  Not reversed  $154 
CT  who was a smoker  unnecessary  support the scan, asking for the results of the previous chest x-ray 
   
had a history of  documentation  and CT scan.  When the provider did not submit those results 
lung nodules.    within 1 week, the MAO denied the request.  The MAO also cited   
Applied MAO  internal clinical criteria that limited CT scans based on the size of 
clinical criteria  nodules and the receipt of chest x-rays.  However, our physician 
not in  panel determined that given the patients history as a smoker, and 
Medicare  the presence of a lung nodule, the case file contained sufficient 
coverage rules  clinical evidence to determine that the requested scan was 
  medically necessary.  A health care coding expert then determined 
that the request met all other applicable Medicare requirements, 
including that the NCD for CT scans does not require prior x-rays 
or that the nodules be a specific size.   
 
D406  Imaging: MRI of  A 91-year-old had  Applied MAO  The MAO denied the service and cited internal clinical criteria  Not reversed  $297 
the lumbar spine  lower extremity  clinical criteria  stating that the patient had not completed 6 weeks of provider-
   
without contrast  pain that radiated  not in  directed treatment in the last 3 months.  However, our physician 
into the upper  Medicare  panel determined the MRI was medically necessary to plan   
leg, hip, and lower  coverage rules  treatment options due to the patients age, symptoms, and results 
back (sciatica).      of a previous back x-ray.  Further, the NCD for MRIs does not state 
Back x-rays  that completion of prior conservative therapy is needed before 
 
showed scoliosis  receiving an MRI.   
and joint disease. 
D397  Imaging:  A 77-year-old had  Determined  The MAO denied the request, stating that conducting a CT in this  Not reversed  $1,400 
Shoulder CT scan  a history of left  that the  context was investigational and, therefore, not covered by 
   
for preoperative  shoulder pain that  request did  Medicare.  However, our physician panel determined that a CT 
evaluation  had progressed  not meet  scan was warranted and within expected standards of care because   
for the last 3  Medicare  it could more accurately assess the condition of the shoulder and 
years. The patient  coverage  determine type of surgery needed.  Further, the applicable NCD 
had received  criteria  did not indicate that the use of a CT scan in this context was 
therapy and  considered investigational.  
injections, but the 
patients 
condition had not 
improved. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to  
Medically Necessary Care, OEI-09-18-00260        Appendix B | 33  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D421  Imaging: CT of  An 81-year-old  Applied MAO  The MAO denied the request and cited internal clinical criteria  Denial  No cost 
chest, abdomen,  had  clinical criteria  which required information to support that the disease had spread  reversed upon  available 
and pelvis  adenocarcinoma  not in  to the cervix or that the tumor was advanced.  However, our  appeal 
of the  Medicare  physician panel determined that the request was consistent with 
endometrium, a  coverage rules  the applicable NCD and had sufficient documentation to show that 
cancer of the  the CT scan was needed to determine the stage of the cancer, 
lining of the  whether it had spread, and to determine the appropriate course of 
uterus.  Required  treatment for the beneficiary.      
unnecessary 
documentation 
D479  Imaging: Chest  A 64-year-old  Applied MAO  The MAO denied the CT scan and cited internal clinical criteria that  Not reversed  $150 
CT  with a pacemaker,  clinical criteria  require prior x-ray imaging results to prove medical necessity.  Our 
diabetes,  not in  physician panel determined the CT scan was needed to exclude a 
hypertension, and  Medicare  life-threatening diagnosis (aneurysm) considering the beneficiarys 
heart valve  coverage rules  symptoms and comorbidities.  Further, the applicable NCD does 
disease was seen  not require that a patient receive an x-ray prior to receiving a CT 
for chest pain and  scan.    
shortness of 
breath.  
D427  Imaging: MRI of  A 75-year-old had  Applied MAO  The MAO denied the MRI request and cited internal clinical criteria  Not reversed  $275 
lower extremity  left hip pain and  clinical criteria  requiring that the beneficiary receive conservative treatments for 6 
joint without  an x-ray showing  not in  weeks.  However, our physician panel determined an MRI was 
contrast  mild degenerative  Medicare  medically necessary due to the beneficiarys signs and symptoms 
changes.  An  coverage rules  of hip changes and altered gait.  Further, NCD guidelines do not 
exam revealed a  require conservative treatment prior to an MRI.   
limp caused by 
the pain.  The 
beneficiary had 
tried nonsteroidal 
anti-inflammatory 
drugs, oral 
steroids, and 
immobilization 
with a brace. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 34  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D472  Imaging: MRI of  A 65-year-old had  Applied MAO  The MAO denied the request (after requesting and not receiving  Denial  $300 
abdomen  a history of chest  clinical criteria  additional records) stating that the beneficiary would need to wait  reversed upon 
pain that radiated  not in  at least 1 year for another MRI given the size of the largest lesion.   appeal 
to the shoulder  Medicare  The MAO cited internal clinical criteria that allowed follow-up MRIs 
and left jaw.  The  coverage rules  only at 12 months for a lesion of 1-2 cm in size or at 6-12 months 
beneficiary had a  for lesions greater than 2-4 cm in size.  A health care coding expert 
previous MRI  Required  determined that the applicable NCD does not restrict the timing of 
showing two  unnecessary  MRIs based on the size of the lesion.  Furthermore, using clinical 
adrenal lesions of  documentation  information already in the case file, the physician panel stated the 
indeterminate  MRI was medically necessary to determine whether the lesions 
origin, the largest  seen on the CT scan were malignant.   
of which was 1.5 
cm. 
D236  Post-acute care:  An 81-year-old  Applied MAO  The MAO denied the request stating that the beneficiary did not  Denial  $425 per day 
Discharge to a  had a history of  clinical criteria  have a need for skilled care in accordance with internal clinical  reversed upon 
skilled nursing  dementia,  not in  criteria.  However, our physician panel determined that the  appeal 
facility (SNF)  hypertension and  Medicare  admission to a SNF was medically necessary and consistent with 
was legally blind  coverage rules  the Medicare Benefit Policy Manual because the beneficiary 
due to glaucoma.   required physician supervision and should have access to physical 
The patient was  and occupational therapy.  
admitted to the 
hospital for 
worsening 
dementia and 
acute agitation.  
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 35  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D260  Post-acute care:  A 64-year-old had  Required  The MAO denied the request stating that it needed to review the  Denial  No cost 
Discharge to a  a diagnosis of  unnecessary  beneficiarys most recent therapy records and suggested that the  reversed upon  available 
SNF  cellulitis (a  documentation  beneficiarys needs could be met either in the current hospital  appeal 
bacterial skin  setting or at a lower level of care (home health services).  Our 
infection) on leg  physician panel determined that the medical records available to 
and bedsores with  the MAO were sufficient to demonstrate that given the 
complaints of  beneficiarys deteriorating functional status and morbidities, the 
worsening  beneficiary should have been discharged to a SNF with access to 
swelling, redness,  physical and occupational therapy.  Further, a health care coding 
and pain in lower  expert determined that the request for a SNF admission was 
right leg.   consistent with the Medicare Benefit Policy Manual. 
D426  Post-acute care:  A 63-year-old had  Determined  The MAO denied the request, stating that the beneficiary did not  Not reversed  No cost 
Discharge to a  a complex  that the  meet coverage criteria for admission to a SNF because the  available 
SNF  medical history  request did  beneficiary may not be able to do 1 to 2 hours of therapy per day.  
including multiple  not meet  Our reviewers determined that SNF was medically necessary for 
chemotherapy  Medicare  this beneficiary and in line with the Medicare Benefit Policy 
regimens,  coverage  Manual.  The beneficiary had multiple ongoing medical conditions 
cognitive  criteria  which need daily skilled nursing care.  Further, the beneficiary 
impairment, and  could have benefited from and tolerated occupational or physical 
prior stroke was  therapy.    
treated in the 
hospital for 
cough, fatigue, 
and shortness of 
breath.   
D270  Post-acute care:  A 67-year-old was  Determined  The MAO denied the request stating that the beneficiarys  Not reversed  No cost 
Discharge to an  diagnosed with  that the  condition did not meet Medicare coverage rules for admission to  available 
inpatient  acute right-sided  request did  an IRF.  However, our physician panel determined that admission 
rehabilitation  ischemic stroke  not meet  to an IRF was medically necessary and in line with the Medicare 
facility (IRF)  and seen at the  Medicare  Benefit Policy Manual.  The beneficiary had difficulty swallowing, 
emergency  coverage  was at significant risk of aspiration and fluid penetration, at high 
department with  criteria  risk for pneumonia, and, therefore, should have been under the 
new onset slurred  frequent supervision of a rehabilitation physician. 
speech. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 36  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D278  Post-acute care:  A 68-year-old had  Determined  The MAO denied the request stating that the beneficiarys  Not reversed  No cost 
Discharge to an  chronic  that the  condition did not meet all medical necessity criteria for admission  available 
IRF  obstructive  request did  to an IRF under Medicare guidelines.  The MAO recommended 
pulmonary  not meet  instead that the beneficiary could be discharged to a SNF, home 
disease,  Medicare  health, or home with outpatient therapy.  Our physician panel 
congestive heart  coverage  determined that the recommendations for outpatient therapy were 
failure, and  criteria  not sufficient and that admission to an IRF was necessary and 
peripheral  consistent with the Medicare Benefit Policy Manual.  The 
vascular disease.   beneficiary had ongoing medical conditions that could generate 
The beneficiary  more medical complications if not closely assessed by a physician 
was admitted to  daily.  The beneficiary also had the ability and need to participate 
the hospital with a  in physical therapy and occupational therapy for 3 hours at least 
femur fracture  5 days per week, needed help with walking, and at least two 
and underwent a  people to help with balance and recovery from the screw 
screw placement  placement in the beneficiarys hip.  
surgery.  After the 
surgery, the 
beneficiary 
developed anemia 
and pneumonia. 
D343  Post-acute care:  An 89-year-old  Determined  The MAO denied the request stating that the beneficiary did not  Denial  $3,039 
Discharge to an  had a history of  that the  have a medical problem that required care in an IRF.  However, our  reversed upon 
IRF  Parkinsons  request did  reviewers determined that the requested inpatient rehabilitation  appeal 
disease, dementia,  not meet  stay met requirements in the Medicare Benefit Policy Manual and 
and prostate  Medicare  was medically necessary because it would allow the beneficiary to 
cancer who had  coverage  regain the ability to perform the activities of daily living that the 
been treated in  criteria  beneficiary was able to do prior to the hospital admission.  
the emergency 
department. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 37  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D393  Post-acute care:  A 75-year-old was  Determined  The MAO denied the request stating that the beneficiary did not  Not reversed  $750 per day 
Discharge to an  hospitalized after  that the  need daily care from a physician, as required by the Medicare 
   
IRF  a motorcycle  request did  Benefit Policy Manual.  However, our physician panel determined 
accident with rib  not meet  that the beneficiary did require this level of care from a physician   
fractures, a  Medicare  due to the beneficiarys complex health needs and medical history 
 
collapsed lung,  coverage  and felt that the beneficiary could tolerate the level of therapy in 
and an acute  criteria  the inpatient rehabilitation facility.  The MAOs medical director 
kidney injury.  The  offered 5 days of skilled nursing care, but our physician reviewer 
beneficiary had a  judged that this alternative care would be insufficient for this 
history of heart  patient. 
attacks, irregular 
heart rate, 
diabetes, and 
chronic 
obstructive 
pulmonary 
disease. 
D224  Injection: Steroid  A 66-year-old  Applied MAO  The MAO denied the request stating that the beneficiary was not  Denial  $261 
injection in the  suffered neck pain  clinical criteria  currently enrolled in or planning to complete formal therapy or a  reversed upon 
 
cervical spine   from degenerative  not in  home exercise program, a requirement from internal clinical  appeal 
disc disease that  Medicare  criteria.  However, our reviewers determined that the injection was 
 
had not improved  coverage rules  medically necessary given the beneficiarys diagnostic test results 
from conservative    and history of completing conservative therapy without relief.    
therapy.  Further, a health care coding expert determined that there was no 
NCD or LCD relevant to this service, and thus there is no Medicare 
requirement that beneficiaries enroll in a therapy or exercise 
program before receiving treatment.  
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to  
Medically Necessary Care, OEI-09-18-00260        Appendix B | 38  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D199  Injection: Botox  An 82-year-old  Required  The MAO denied the request and cited a lack of clinical  Not reversed  $3,674 
injection for urge  was diagnosed  unnecessary  information about the beneficiarys previous medication use and 
(MAO noted 
incontinence  with urge  documentation  asked for additional records.  However, the MAO had already 
that it reversed 
incontinence.   received records documenting this information as part of the prior 
the denial after 
Beneficiary had  authorization request, making the request for additional 
receiving OIGs 
been receiving  documentation unnecessary.   
data request) 
Botox injections, 
but the 
effectiveness was 
perceived to be 
wearing off, so 
requested a 
stronger dose. 
D416  Injection:  A 66-year-old had  Required  The MAO denied the injection request after asking for more  Not reversed  No cost 
Sacroiliac joint  lower back pain  unnecessary  documentation.  The MAO stated that the available doctors notes  available 
injection for pain  that radiated into  documentation  did not support medical necessity.  Our physician panel 
management   the legs.  Patient  determined that, based on the information available in the case 
had both knees  file, the injection was medically necessary as opioids and anti-
replaced and used  inflammatory medications were not reasonable alternatives to 
a shoe lift to treat  manage the patients pain.  Further, our health care coding expert 
a leg length  determined that the request met requirements in the applicable 
discrepancy.  LCD.  
Patient 
experienced 
significant pain 
when standing or 
walking with no 
improvement 
from previous 
conservative 
treatments. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 39  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D339  Injection:  A 75-year-old had  Applied MAO  The MAO denied the request stating that the beneficiarys blood  Not reversed  $754 
Injection to treat  low blood iron  clinical criteria  counts were not low enough to meet requirements established in 
anemia   level caused by  not in  internal clinical criteria.  Our reviewers determined that the 
abnormal kidney  Medicare  requested item was necessary and reasonable given the downward 
function.  coverage rules  trend in the beneficiarys hemoglobin count, and that the 
beneficiary met the requirements in the applicable NCD.  
D401  Injection: Upper  A 72-year-old had  Determined  The MAO denied the service stating that per Medicare coverage  Not reversed  $238 
cervical spine  severe, worsening  that the  rules, the requested injections were covered only for the lower 
(C1-2) joint  neck pain, and  request did  areas of the spine, and not at the C1-2 joint.  However, our health 
injection  scans showed  not meet  care coding expert determined that the LCD referenced by the 
deterioration and  Medicare  MAO does not preclude the use of injections in the C1-2 joint.  
changes in spine.   coverage  Further, our physician panel determined that an injection at this 
Beneficiary had  criteria  level is a reasonable diagnostic and therapeutic option and that 
tried other  the service was medically necessary given the beneficiarys chronic, 
conservative  continuous pain. 
treatments with 
limited 
improvement. 
D475  Injection:  A 59-year-old had  Determined  The MAO denied the request stating that the number of injections  Not reversed  $95 
Cervical/ thoracic  a diagnosis of  that the  requested exceeded the Medicare coverage limit of (1) one to two 
facet injection  spondylosis   request did  injections per section of the spine per session, or (2) up to five 
(degenerative  not meet  injection sessions in a 12-month period.  However, our health care 
osteoarthritis of  Medicare  coding expert determined that the LCD the MAO cited does not 
the spine) and a  coverage  include a limit on the number of injections per section of the spine 
history of neck  criteria  per session, and that the requested session would not cause the 
pain, low back  beneficiary to exceed five sessions in a 12-month period.  Further, 
pain, and pain in  our physician panel determined that the injection was medically 
both hips.    necessary and noted that the beneficiary experienced significant 
relief from two previous injection sessions.   
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 40  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D232  Durable medical  A 93-year-old had  Manual review  The MAO denied the request, incorrectly stating that the only  Not reversed  $150/month 
equipment:  a history of  error  diagnosis listed in the beneficiarys medical records was 
   
Hospital bed with  epilepsy, early    hypertension.  This finding led it to determine that the beneficiary 
rails  onset Alzheimers,  Applied MAO  did not meet internal clinical criteria for a hospital bed because   
rheumatoid  clinical criteria  there was no indication of a condition requiring positioning that 
arthritis, chronic  not in  could not be accommodated by a standard bed.  However, our 
back pain, knee  Medicare  reviewers determined the request was medically necessary and in 
and joint stiffness,  coverage rules  accordance with the NCD for hospital beds due to the beneficiarys 
and limited range    chronic conditions and movement limitations.    
of motion.   
D294  Durable medical  An 83-year-old  Applied MAO  The MAO denied the request based on internal guidelines stating  Not reversed  $1,476 
equipment:  had progressive  clinical criteria  that the lift would not improve the beneficiarys balance or 
 
Hydraulic lift  cognitive  not in  ambulation and that it is only for beneficiaries who require 
impairment,  Medicare  complete assistance with sit-to-stand transfers.  However, our   
progressive  coverage rules  physician panel determined that this item was medically necessary 
decline in walking,    given the patients mobility needs and progressive weakness and 
cervical spine  to decrease the risk of falls during transfers to and from bed.  
stenosis, and  Further, our reviewers determined that the proposed use was 
worsening urinary  consistent with the applicable LCD.    
incontinence. 
D419  Durable medical  A 57-year-old had  Required  MAO denied the request after requesting more documentation  Not reversed  No cost 
equipment:  multiple sclerosis,  unnecessary  from the beneficiarys doctor.  The MAO stated that the patient did  available 
   
Manual  hypertension,  documentation  not meet wheelchair criteria from Medicare coverage rules, such as 
wheelchair   bladder  documentation of whether the beneficiary could propel the   
dysfunction, tibia  wheelchair and whether it could be used in the beneficiarys home.  
fracture, and  However, our reviewers found that there was already 
mobility issues  documentation in the beneficiarys file that demonstrated the 
related to  beneficiary met established criteria in the applicable LCD.  Further, 
activities of daily  our physician panel determined a wheelchair was medically 
living.   necessary because of the beneficiarys fractured tibia. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to  
Medically Necessary Care, OEI-09-18-00260        Appendix B | 41  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D460  Durable medical  A 76-year-old had  Applied MAO  The MAO denied the request and cited internal clinical criteria,  Not reversed  $112 
equipment:  a history of joint  clinical criteria  stating that the beneficiary was not eligible to receive a walker 
Walker  pain, post-polio  not in  because the beneficiary had already received a cane within the 
syndrome, ankle  Medicare  past 5 years.  The internal clinical criteria considered a cane and 
and foot surgery,  coverage rules  walker to be same or similar devices and limited beneficiaries to 
and was at-risk for  one such device every 5 years.  However, according to our 
falls.  physician panel, a cane was not stable enough given the 
beneficiarys history of polio and arthritis, fall risk, and physical 
therapy notes that the right knee buckled and the right shoulder 
was in pain.  Further, our health care coding expert determined 
that the LCD for walkers did not include a 5-year restriction on 
more than one ambulatory device. 
D320  Physician  An 85-year-old  Applied MAO  The MAO denied the consultation stating that there was no  Not reversed  $286 
services:  had type 2  clinical criteria  evidence that the beneficiary experienced restricted blood flow or 
Interventional  diabetes with  not in  a blockage of the arteries, as required by internal clinical criteria.  
radiology consult  polyneuropathy  Medicare  However, the applicable NCD includes no such requirement and 
and follow-up for  (dysfunction in  coverage rules  our physician panel determined this service was medically 
peripheral arterial  the nerves) and  necessary given the beneficiarys unstable condition and lack of 
disease   venous  sensation below the hips. 
insufficiency 
(restricted blood 
flow from the 
limbs to the 
heart). 
D300  Physician  An 80-year-old  Determined  The MAO denied the request for a follow-up visit to the physician  Denial  $1,641 
services: Referral  received  that the  who treated the beneficiary in the emergency department citing  reversed after 
for a follow-up  treatment in the  request did  Medicares prohibition against self-referral by physicians.   provider 
office visit after  emergency  not meet  However, the MAO determined that the original denial was  inquiry 
an emergency  department for a  Medicare  inappropriate because Medicare self-referral rules make an 
department visit.  fractured  coverage  exception for emergency department follow-up care.  
humerus.    criteria 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 42  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D463  Physician  A 72-year-old had  Applied MAO  The MAO denied the followup visit citing internal clinical criteria,  Not reversed  $140 
services: Breast  a  history of  clinical criteria  but it did not indicate the specific criteria that were not met.  
cancer follow-up  breast cancer  not in  However, Medicare does not have a policy that explicitly addresses 
visit with a  surgery and  Medicare  followup visits after cancer treatment.  Further, our physician panel 
radiation  partial  coverage rules  determined that the visit with the radiation oncologist was 
oncologist  mastectomy.  medically necessary and reasonable, as there may be potential 
cardiac, pulmonary and other complications from breast radiation 
and the most appropriate physician to evaluate these would be the 
radiation oncologist, who would then be able to make appropriate 
treatment and referral decisions on the patient's behalf. 
D193  Surgery:  A 74-year-old was  Applied MAO  The MAO denied the request stating that the beneficiarys medical  Denial  $1,096 
Implantation of a  diagnosed with  clinical criteria  records lacked evidence that the beneficiary experienced  reversed after 
neurostimulator  full incontinence  not in  incontinence episodes for at least 2 weeks over a 6-month period,  peer to peer 
device that can  of feces.  The  Medicare  criteria established in internal MAO review guidelines.  Our  was conducted 
treat bowel  beneficiary had  coverage rules  reviewers determined that the service was necessary and  by Medical 
incontinence   involuntary stool  consistent with the applicable NCD based on documentation  Director with 
and gas leakage  Required  showing that the beneficiary had, for years, tried more  additional 
that had not  unnecessary  conservative treatments with no improvement.  information 
improved with  documentation 
other conservative 
treatments. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 43  Case  Service  Beneficiary  Denial cause  Denial summary  Resolution at  Cost (actual 
ID  requested  profile  time of OIG  or 
data request  estimated) 
D207  Surgery: Reverse  A 72-year-old  Applied MAO  The MAO denied the request stating that the beneficiary did not  Not reversed  No cost 
total arthroplasty  experienced pain  clinical criteria  meet requirements from internal clinical criteria, such as providing  available 
-a surgical in the right  not in  the results from an exam that uses physical manipulation of the 
procedure that shoulder for years.   Medicare  joint to test for pain and confirmation from an MRI that the tendon 
repairs and An x-ray  coverage rules  structures needed repair.  However, our physician panel 
provides a demonstrated  determined that there was already sufficient clinical information in 
prosthetic osteoarthritis and  the beneficiarys medical records to justify the joint replacement 
replacement for a physical exam  with the tendon structure repair based on the beneficiarys history, 
the shoulder joint indicated a  physical exam, and x-ray.  Further, Medicare does not have an NCD 
(including the Popeye deformity  or LCD specific to reverse shoulder arthroplasty and so does not 
rotator cuff tear (reflecting an  require the results of these tests for approval.   
and biceps abnormal 
tendon) shortening or 
displacement of 
the bicep muscle).  
The patient had 
completed 6-
weeks of physical 
therapy.    
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 44  Payment Denials That Met Medicare coverage rules and MAO billing rules 
Case  Service received  Beneficiary  Denial cause  Denial summary  Resolution at time  Cost: 
ID  profile  of OIG data  actual or 
request  estimated 
D489  Imaging: x-rays of  A 67-year-old  Manual review error  The MAO denied payment stating that there was no prior  Denial reversed  $102 
shoulders and  had lupus and  authorization on file. The provider disputed the denial,  after provider 
knees  osteoarthritis.  Misapplied MAO  stating that no prior authorization was required for that  dispute 
rule  service and the MAO agreed.  
D178  Imaging: MRI of  A 20-year-old  Manual review error  The MAO denied payment for the service, stating that it  Not reversed  $73 
the lower spine  was diagnosed  needed documentation from the beneficiarys primary 
(MAO noted that it 
with lumbar  insurance carrier.  After OIGs data request, the MAO 
reversed the denial 
spondylosis  acknowledged that the requested documentation was 
after receiving OIGs 
(degeneration in  already included in the original claim.   
data request) 
the bones of the 
spine).  
D383  Imaging:  A 48-year-old  System processing  The MAO denied the payment, stating that services  Not reversed  $73 
Echocardiogram, a  was diagnosed  error  received during an inpatient stay required prior 
(MAO noted that it 
type of imaging  with heart  authorization.  After OIGs data request, the MAO 
reversed the denial 
test of the heart  disease received  acknowledged that it had a prior authorization on file 
after receiving OIGs 
an  already, but had not identified it because non-behavioral 
data request) 
echocardiogram  services (e.g., the echocardiogram) were billed to a 
during an  separate entity from behavioral services (e.g., the 
inpatient  patients inpatient psychiatric admission).   
psychiatric 
admission.  
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 45  Case  Service received  Beneficiary  Denial cause  Denial summary  Resolution at time  Cost:  
ID   profile  of OIG data  actual or 
request  estimated 
D019   Durable medical  A 65-year-old  System processing  MAO denied payment stating that the nebulizer was  Denial reversed  $5 
equipment: Home  had chronic  error  being rented from an out of network provider.  However,  after provider   
nebulizer rental  obstructive    because a participating provider had issued a referral for  dispute  
(nebulizers change  pulmonary  Misapplied MAO  this service, the MAOs requirements for plan directed   
medication from  disease (a  rule  care had been met.     
liquid to mist)  chronic     
inflammatory   
lung disease that   
causes   
obstructed 
airflow from the 
lungs).  
D024   Durable medical  A 68-year-old  System processing  MAO denied payment stating that the service had not  Denial reversed  $22 
equipment:  uses a  error  been authorized.  Upon review, the MAO found that an  after provider 
Wheelchair rental  wheelchair.  authorization had been approved but that the MAO had  dispute 
  failed to link the authorization number to the payment   
request.     
 
D073  Physician services:  A 58-year-old  System processing  The MAO denied payment stating that the required prior  Denial reversed  $82 
Radiation treatment  had skin cancer  error  authorization was not on file.  However, the provider  after provider 
consultation  of the nose.    submitted a copy of an authorization letter from the  dispute 
MAO that included the service and date of service.    
 
 
D096   Physician services:  A 73-year-old  System processing  The MAO denied payment stating that payment for the  Denial reversed  $230 
Hospital visit for  received critical  error  services should be bundled.  However, after the provider  after provider   
respiratory failure  care services    disputed the claim, the MAO later determined these  dispute    
from a physician.     services had in fact been billed correctly.      
   
 
 
 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to  
Medically Necessary Care, OEI-09-18-00260        Appendix B | 46  Case  Service received  Beneficiary  Denial cause  Denial summary  Resolution at time  Cost:  
ID   profile  of OIG data  actual or 
request  estimated 
D119   Physician services:  A 73-year-old  System processing  The MAO denied payment for the visit, stating that no  Denial reversed  $114 
Eye exam and  with glaucoma  error  prior authorization was in place for the out-of-network  after provider 
treatment  received an  provider.  A prior authorization had been approved for  dispute 
ophthalmological  the procedure but listed a different, though related,   
exam.   procedure code than the one included on the claim.  The   
provider resubmitted the claim showing the existing 
prior authorization.  The MAO acknowledged that either 
procedure code could have been used to pay the claim 
and that the original claim was denied in error. 
 
D177   Physician services:  A 57-year-old  Manual review error  The MAO denied the payment stating that there was no  Not reversed  $81 
Office visit  visited the doctor  prior authorization on file.  After OIGs data request, the 
(MAO noted that it 
for a sinus  MAO acknowledged that a prior authorization was not 
reversed the denial 
infection.  needed because the provider was in-network and had 
after receiving OIGs 
been marked out of network due to a manual error.  The 
data request) 
MAO reversed the denial and paid the provider.  
D187   Physician services:  An 85-year-old  Manual review error  The MAO denied the payment for lack of prior  Not reversed  $50 
Treatment of  was being    authorization.  Typically, the MAO required a beneficiary 
(MAO noted that it 
chronic ulcer on the  treated in a  Misapplied MAO  to receive a prior authorization to use a non-contracted 
reversed the denial 
foot  skilled nursing  rule  provider.  However, because the beneficiary was in an in-
after receiving OIGs 
facility.   network skilled nursing facility, the claim met the MAO 
data request) 
  and CMS requirement for plan directed care and, 
  therefore, no prior authorization was required.      
 
D385   Surgery: Breast  A 72-year-old  Manual review error   The MAO denied payment for the procedure stating that  Not reversed  $4,043 
reconstruction  had a cancerous    the service was not covered.  However, the MAOs claims 
(MAO noted that it 
surgery  breast tumor.    analyst incorrectly denied the entire claim, rather than 
reversed the denial 
denying several line items that were noncovered services.  
after receiving OIGs 
The MAO paid the claim after it discovered the error.   
data request) 
 
 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to  
Medically Necessary Care, OEI-09-18-00260        Appendix B | 47  Case  Service received  Beneficiary  Denial cause  Denial summary  Resolution at time  Cost: 
ID  profile  of OIG data  actual or 
request  estimated 
D090  Surgery: Intestinal  A 67-year-old  System processing  The MAO denied payment for the procedure stating that  Denial reversed  $1,985 
obstruction  had laparoscopic  error  the claim was submitted too late.  However, the provider  after provider 
surgery to  submitted evidence that the invoice had been previously  dispute 
remove an  submitted to the MAO.  
obstruction in 
stomach.  
D128  Surgery: Cardiac  An 80-year-old  System processing  The MAO denied payment for the service, incorrectly  Not reversed  $401 
surgical procedure       u  n  derwent  error  stating that there was no prior authorization on file.  
(MAO noted that it 
surgery for the  Although the beneficiary had received prior authorization 
reversed the denial 
removal and  for the surgery, the MAO denied the providers payment 
after receiving OIGs 
replacement of a  request six times. 
data request) 
defibrillator, an 
implanted device 
to help control 
pacing of the 
heart.  
D454  Inpatient hospital:  A 93-year-old  System processing  The MAO denied payment for two service codes, stating   Not reversed  $502 
Inpatient admission  was  diagnosed  error  that the diagnosis codes were listed incorrectly on the 
and advanced care  with congestive  claim.  However, our reviewers found that of the two 
planning  heart failure,  services on the claim, one was correctly coded and 
anemia, coronary  should not have been denied.  
artery disease 
and 
myelodysplastic 
syndrome (a 
disorder of the 
production of 
blood cells). 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 48  Case  Service received  Beneficiary  Denial cause  Denial summary  Resolution at time  Cost:  
ID   profile  of OIG data  actual or 
request  estimated 
D183   Inpatient hospital:  A 72-year-old  Manual review error  The MAO denied the payment because the request did  Not reversed  $6,218 
Hospitalization  went to the  not have required information, such as discharge 
(MAO noted that it 
after emergency  emergency room  summary and physicians notes and orders.  After OIGs 
reversed the denial 
room visit   and was  data request, the MAO acknowledged that the 
after receiving OIGs 
diagnosed with a  information had already been received and ultimately 
data request) 
pulmonary  reversed the denial.  
embolism, a   
blockage in the 
arteries in the 
lungs.  
 
D440   Inpatient hospital:  An 80-year-old  Applied MAO clinical  The MAO denied the providers request for inpatient  Not reversed  $9,516 
Inpatient admission  went to the  criteria not in  admission based on internal clinical criteria and stated 
 
emergency room;  Medicare coverage  that the patient did not need an inpatient level of care.  
 
the patient had  rules  The MAO offered a lower level of care: observation.  
fallen 24 hours    However, our physician panel determined that the 
before and was  patients age and health concerns, such as a fall at home 
unable to get up.   and hip fracture, required a higher level of care than an 
Beneficiary was  observation stay would have provided.  
diagnosed with a 
fracture in the 
thigh bone 
(femur).  
 
D116   Ambulance:  A 61-year-old  System processing  The MAO denied payment for an ambulance trip because  Denial reversed  $274 
Ambulance ride to  with sepsis was  error  it had exceeded coverage limits on costs.  When the  after provider 
a health care facility  transported by  provider filed a dispute, the MAO acknowledged that the  dispute 
ambulance to the  contract had been updated and the ambulance ride 
hospital.   should have been covered. 
 
D375   Ambulance:  An 80-year-old  System processing  The MAO denied payment for the ambulance transport  Not reversed  $2,627 
Ambulance  fell at home and  error  for being out of area.  The provider resubmitted the 
(MAO noted that it 
transport to  was transported  claim six times.  After OIGs data request, the MAO 
reversed the denial 
hospital  by ambulance to  determined that the calculation of out of area was 
after receiving OIGs 
the hospital.   completed using ground mileage rather than air mileage 
data request) 
and, therefore, was incorrect.  
 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to  
Medically Necessary Care, OEI-09-18-00260        Appendix B | 49  Case  Service received  Beneficiary  Denial cause  Denial summary  Resolution at time  Cost: 
ID  profile  of OIG data  actual or 
request  estimated 
D060  Lab tests:  A 53-year-old  System processing  The MAO denied payment stating that the approved  Not reversed  $30 
Collection of blood  was diagnosed  error  prior authorization only covered chemotherapy and 
sample (blood  with multiple  medications related to cancer treatment and not the lab 
draw)  myeloma, a type  work.  However, after reviewing the case file, our health 
of cancer.   care coding expert found that a valid prior authorization, 
which covered lab work, was in effect on the date of 
service.   
D135  Lab tests: Lab work  A 70-year-old  System processing  The MAO denied payment, stating that it had a capitated  Not reversed  $54 
using a blood  with  error  contractual agreement for the provider to cover lab 
(MAO noted that it 
sample  lymphedema  work, meaning the MAO did not need to pay the hospital 
reversed the denial 
received  separately for lab services.  After the MAO received OIGs 
after receiving OIGs 
laboratory work  data request, it discovered that the capitated contractual 
data request) 
on a blood  agreement had ended prior to the denial and thus the 
sample.   denial was inappropriate.   
D444  Therapy: Physical  An 83-year-old  System processing  MAO denied payment, incorrectly stating that the  Not reversed  $108 
therapy  had issues with  error  provider was out-of-network.  The MAOs established 
(MAO noted that it 
gait and mobility  procedure was to manually review payment requests for 
reversed the denial 
following a  providers with multiple taxpayer identification numbers, 
after receiving OIGs 
stroke.   which did not happen for this payment request.  The 
data request) 
MAO investigated this case after receiving OIGs data 
request and determined, using the correct taxpayer 
identification number, that the provider was in-network.  
D103  Therapy: Home  A 91-year-old  System processing  The MAO denied payment stating that it was filed too  Denial reversed  $275 
skilled nursing visit  received a home  error  late after the date of service.  The provider submitted  after provider 
and physical  skilled nursing  evidence showing the claim had been filed within the  dispute 
therapy evaluation  visit and physical  required timeframe.  
therapy 
evaluation. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 50  Case  Service received  Beneficiary  Denial cause  Denial summary  Resolution at time  Cost: 
ID  profile  of OIG data  actual or 
request  estimated 
D441  Radiation  A 74-year-old  System processing  The MAO denied payment stating that no prior  Denial reversed  $668 
treatment:  was diagnosed  error  authorization was on file.  The provider disputed the  after provider 
Intensity  with prostate  denial and submitted a screenshot demonstrating that  dispute 
Modulated  cancer.  prior authorization had previously been obtained for the 
Radiation  date of service.  The MAO acknowledged an error in 
Treatment Delivery  which the number of authorized days was not being 
(a type of radiation  recognized in its system. 
therapy to treat 
cancer) 
D442  Radiation  A 78-year-old  Manual review error  MAO denied payment stating there was no prior  Denial reversed  $336 
treatment: Delivery  was diagnosed  authorization on file.  The provider disputed the denial  after provider 
of Radiation  with pancreatic  and included a screenshot demonstrating that the MAO  dispute 
treatment  cancer.   had granted a prior authorization for the billed claim.  
The MAO indicated that the denial resulted from human 
errorthe claim processor did not recognize that there 
was an authorization on file. 
D433  Chiropractic:  A 70-year-old  Manual review error  MAO denied payment stating there was no prior  Not reversed  $25 
Chiropractic  was diagnosed  authorization on file.  However, after OIGs data request, 
(MAO noted that it 
manipulative  with  the MAO found that a prior authorization had previously 
reversed the denial 
treatment  radiculopathy, a  been extended to cover the date of service, so the claim 
after receiving OIGs 
pinched nerve  should have been approved.  
data request) 
along the spine. 
D435  Other test:  An 85-year-old  Incorrectly  MAO denied part of the claim as a duplicate service,  Not reversed  $66 
Electrocardio-gram,  was diagnosed  determined that the  citing edits from the National Correct Coding Initiative.  
(MAO noted that it 
a procedure that  with tachycardia,  request did not meet  After OIGs data request, the MAO indicated that the edit 
reversed the denial 
records electrical  rapid heartbeat,  Medicare coverage  had been incorrectly applied because the services were 
after receiving OIGs 
signals from the  and previously  criteria  rendered by physicians with different subspecialties. 
data request) 
heart  had abnormal 
electrocardiogra
m results.  
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to 
Medically Necessary Care, OEI-09-18-00260  Appendix B | 51  APPENDIX C 
Characteristics of Sampled MAOs 
The 15 MAOs included in this review varied in size, enrolling between 165,000 and 5.9 
million Medicare beneficiaries in 2019.  Service areas for these MAOs covered all 50 
States, the District of Columbia, and five territories (American Samoa, Guam, 
the Northern Mariana Islands, Puerto Rico, and the U.S. Virgin Islands.)   
MAO  Number of enrolled  Number of States or 
beneficiaries in 2019  territories in service area 
UnitedHealth Group, Inc.  5,857,700  56 
Humana Inc.  3,922,929  52 
CVS Health Corporation  2,249,248  54 
Kaiser Foundation Health Plan, Inc.  1,617,713  8 
Anthem Inc.  1,135,946   56 
WellCare Health Plans, Inc.  532,053  54 
Blue Cross Blue Shield of Michigan  520,485  54 
Centene Corporation  259,356  48 
InnovaCare Inc.  249,523  15 
Highmark Health  227,298  54 
SCAN Health Plan  203,766  1 
UPMC Health System  191,460  54 
Medical Card System, Inc.  174,157  1 
Healthfirst, Inc.  165,266  51 
EmblemHealth, Inc.  165,238  54 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About 
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Appendix C | 52   APPENDIX D - AGENCY COMMENTS
DATE:  March 24, 2022 
TO:  Suzanne Murrin 
Deputy Inspector General for Evaluation and Inspections 
FROM:  Chiquita Brooks-LaSure 
Administrator 
SUBJECT:  Office of Inspector General (OIG) Draft Report: Some Medicare Advantage 
Organization Denials of Prior Authorization Requests Raise Concerns About 
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260 
The Centers for Medicare & Medicaid Services (CMS) appreciates the opportunity to review and 
comment on the Office of Inspector Generals (OIG) draft report. CMS is committed to its 
oversight and enforcement of the requirements of the Medicare Advantage program.   
Medicare Advantage plans are Medicare-approved managed care plans offered by Medicare 
Advantage Organizations (MAOs), which are private companies, as an alternative to original 
Medicare. MAOs must generally cover the same benefits as original Medicare. However, as part 
of the managed care structure, MAOs may apply internal coverage policies that are no more 
restrictive than original Medicares national and local coverage policies to ensure that plan-
covered items and services are medically necessary and appropriately targeted to the 
beneficiarys condition and diagnostic needs. MAOs are required to establish and maintain 
written standards, such as coverage rules, practice guidelines, payment policies, and utilization 
management policies, that allow for individual medical necessity determinations.   
MAOs must follow national and local Medicare coverage determinations (NCDs and LCDs) and 
coverage guidance specified in original Medicare manuals, if specific guidelines exist for a given 
service. However, in many cases, NCD or LCD requirements are broad enough that an MAO 
may implement additional coverage requirements to better define the need for the service, as 
long as these additional requirements do not violate the requirements of the applicable NCD or 
LCD. Where there are no applicable NCDs or LCDs, MAOs may establish coverage guidelines, 
as long as the MAOs guidelines are supported by medical evidence. Additionally, for services 
that are not subject to existing LCD and NCD requirements, MAOs may apply third-party 
guidelines, such as guidelines used by contractors engaged by the MAO to make coverage 
determinations. 
CMS uses several tools to oversee the Medicare Advantage program and help ensure enrollees 
have adequate access to health care services. For example, CMS conducts annual audits of a 
sample of MAOs to evaluate compliance with the terms of the MAOs contracts with CMS; in 
particular, the requirements associated with access to medical services, drugs, and other enrollee 
protections required by Medicare. CMS also targets audits to areas of concern, such as service 
types with a high rate of denial. CMS notifies plans of noncompliance, such as when it believes a 
plans coverage is more restrictive than under original Medicare and represents a possible barrier 
to accessing care. MAOs are required to submit corrective action plans to address cited 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260 Appendix D | 53 deficiencies. Plans that are found to have repeated violations are subject to increasing penalties, 
including Civil Monetary Penalties, intermediate sanctions (suspension of payment, enrollment, 
and/or marketing activities), and even contract terminations.  
In recent years, CMS has increased the transparency of audit findings by publishing them on the 
Medicare.gov website and developing a publicly available audit annual report with best practices 
MAOs can adopt to continue improving performance. Our oversight efforts are yielding positive 
results, with the average number of issues cited per audit declining approximately 70 percent 
from 2012 to 2019. In addition, CMS has populated information on the Medicare Plan Finder 
website to provide beneficiaries with information on MAO performance. In addition to the Star 
Ratings mentioned in this report, CMS has utilized the enrollment function in Medicare Plan 
Finder to cease enrollment in MAOs that fail to meet certain requirements. In addition, CMS 
continues to examine ways in which we can use technology tools to streamline processes like 
prior authorization to make them less burdensome on patients and providers.  
While the Medicare Advantage payment denial rate is an important area to continue to monitor 
closely, CMS notes that the overall Medicare Advantage payment request denial rate cited by 
OIG for 2018 (9.5 percent) is comparable to the original Medicare denial rate during the same 
time period. 
OIGs recommendations and CMS' responses are below. 
OIG Recommendation 
CMS should issue new guidance on the appropriate use of MAO clinical criteria in medical 
necessity reviews. 
CMS Response 
CMS concurs with this recommendation. CMS plans to issue clarifying guidance regarding 
appropriate use of clinical criteria in medical necessity reviews. 
OIG Recommendation 
CMS should update its audit protocols to address the issues identified in this report, such as 
MAO use of clinical criteria and/or examining particular service types. 
CMS Response 
CMS concurs with this recommendation. CMS will update its audit protocol if changes are 
necessary to align its audit processes with the guidance CMS plans to issue under Recommendation 
1. Similarly, CMS will update its auditor training materials if changes are necessary as a result of
the guidance CMS plans to issue under Recommendation 1.
OIG Recommendation 
CMS should direct MAOs to take additional steps to identify and address vulnerabilities that can 
lead to manual review and system errors. 
CMS Response 
CMS concurs with this recommendation. CMS will direct MAOs to examine their manual review 
and system programming processes and address vulnerabilities that may result in inappropriate 
denials in keeping with clarifying guidance that CMS plans to issue under Recommendation 1. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260                                                                        Appendix D | 54 CMS thanks OIG for their efforts on this issue and looks forward to working with OIG on this and 
other issues in the future. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About
Beneficiary Access to Medically Necessary Care, OEI-09-18-00260                                                                        Appendix D | 55 ACKNOWLEDGMENTS AND CONTACT 
Acknowledgments 
Rosemary Rawlins Bartholomew and Linda Min served as the team leaders for this 
study.  Others in the Office of Evaluation and Inspections who conducted the study 
include Camille Harper, Eunji Kim, and Ivy Ngo.  Office of Evaluation and Inspections 
staff who provided support include Joe Chiarenzelli, Kevin Farber, Robert Gibbons, 
and Christine Moritz. 
This report was prepared under the direction of Blaine Collins, Regional Inspector 
General for Evaluation and Inspections in the San Francisco regional office and 
Abby Amoroso, Deputy Regional Inspector General. 
Contact 
To obtain additional information concerning this report, contact the Office of Public 
Affairs at Public.Affairs@oig.hhs.gov.  OIG reports and other information can be found 
on the OIG website at oig.hhs.gov. 
Office of Inspector General 
U.S. Department of Health and Human Services 
330 Independence Avenue, SW 
Washington, DC 20201 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise 
Concerns About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  Acknowledgments and Contact | 56  ABOUT THE OFFICE OF INSPECTOR GENERAL 
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: 
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 audits help reduce waste, abuse, and mismanagement and promote economy 
and efficiency throughout HHS. 
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. 
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. 
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 OIGs 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. 
Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns  
About Beneficiary Access to Medically Necessary Care, OEI-09-18-00260  About OIG | 57