Wallace M. Green, PA-C, CR6394 (2023)

DECISION

I sustain the determination of a Medicare contractor, as affirmed on reconsideration by the Centers for Medicare & Medicaid Services (CMS), to revoke the Medicare enrollment and billing privileges of Petitioner, Wallace M. Green, PA-C, and to place him on the Preclusion List. 

I. Background and Rulings

This case was recently transferred to me from the docket of another administrative law judge.  The parties filed pre-hearing briefs and proposed exhibits prior to the case being transferred.  CMS filed exhibits identified as CMS Ex. 1 – CMS Ex. 77.¹  Petitioner filed exhibits identified as P. Ex. 1 – P. Ex. 4.² 

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Petitioner objects to my receiving the written direct testimony of Debra Patterson, M.D., CMS Ex. 67, contending that Dr. Patterson lacks the experience and training necessary to render an expert opinion in this case.  CMS offers Dr. Patterson’s testimony as opinion that Petitioner’s prescriptions of certain controlled substances to patients, including Medicare beneficiaries, constitute a pattern or practice of improperly prescribing these medications to individuals who already were receiving large doses of opioids that had been prescribed by Petitioner’s physician supervisor.  Petitioner argues that Dr. Patterson is not actively treating patients, nor has she done so for an extended period, and has not obtained training in pain management, addiction, psychiatry, or neurology.  Petitioner Wallace Green, PA-C’s Objection to Respondent’s Witness and Witness Report. 

I overrule the objection.  Dr. Patterson is qualified to address the question of whether Petitioner exhibits a pattern of inappropriate or improper prescription of controlled substances to patients who were already receiving large doses of opioids.  Knowledge of the use of these drugs and the circumstances under which prescription of them is proscribed falls within Dr. Patterson’s training and experience as a physician practicing internal medicine and as a medical director for a Medicare contractor. 

CMS objects to my receiving the written direct testimony of Paul Lynch, M.D., P. Ex. 1, asserting that Dr. Lynch has not demonstrated the training and background necessary to render an opinion as to the statistical significance of evidence relating to Petitioner’s prescription practice.  CMS also objects to portions of Dr. Lynch’s testimony as irrelevant.  The Centers for Medicare & Medicaid Services’ Objection to Petitioner’s Proposed Witnesses and Exhibits. 

I overrule these objections.  They address the weight of Dr. Lynch’s testimony and not his credentials as a physician expert on pain management.  I address Dr. Lynch’s opinions and their probative value in the text of this decision. 

CMS objects additionally to my receiving P. Ex. 3.  This voluminous exhibit consists of records of thousands of prescriptions that Petitioner ordered while practicing as a physician’s assistant.  I exclude this exhibit because it is irrelevant.  There is no dispute in this case as to what Petitioner prescribed to his patients.  Rather, the determination to revoke and my decision hinge on the propriety of Petitioner’s prescriptions to Medicare beneficiaries.  Petitioner has not shown how P. Ex. 3 relates to that issue. 

I receive into the record CMS Ex. 1 – CMS Ex. 77 and P. Ex. 1, P. Ex. 2, and P. Ex. 4. 

CMS’s exhibits include the testimony of Dr. Patterson, and Kenneth Risko, BS Pharm, MBA.  CMS Ex. 67; CMS Ex. 68.  Petitioner offered the testimony of Dr. Lynch and Mitchell S. Nudelman, M.D., J.D.  P. Ex. 1; P. Ex. 4.  Neither CMS nor Petitioner filed a written request to cross-examine any of these witnesses.  Consequently, I find no reason

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to convene an in-person hearing and I decide this case based on the parties’ written submissions.³ 

1. II. Issues, Findings of Fact and Conclusions of Law
   1. A. Issues

The issues are whether CMS may revoke Petitioner’s Medicare enrollment and billing privileges and place Petitioner on the Preclusion List. 

1. 2. B. Findings of Fact and Conclusions of Law
      1. 1. Revocation of Petitioner’s Medicare enrollment and billing privileges

The Medicare contractor and CMS invoked 42 C.F.R. § 424.535(a)(14)(i) as authority for revoking Petitioner’s Medicare enrollment and billing privileges.  The regulation allows for revocation where CMS determines that a physician or an eligible professional (including a physician’s assistant) has a pattern or practice of prescribing drugs, including controlled substances, that is abusive or that represents a threat to the health and safety of Medicare beneficiaries.  The regulation directs CMS to consider a variety of factors in determining whether a basis exists for revocation.  These factors include whether the physician or physician’s assistant has prescribed controlled substances in excessive dosages that are linked to patient overdoses, and any other information that is relevant.  42 C.F.R. § 424.535(a)(14)(i)(C), (H). 

CMS may not rely on the regulation to revoke arbitrarily an individual’s Medicare enrollment and billing privileges.  The regulation makes it plain that the individual must exhibit a pattern or practice of writing abusive prescriptions or prescriptions that threaten beneficiaries’ health and safety as a prerequisite for revocation.  However, the regulation also vests discretion in CMS to determine whether such a pattern or practice exists.  In reviewing CMS’s determination, I may not second-guess CMS or substitute my judgment for that of the agency.  I must sustain CMS’s determination to revoke enrollment and billing privileges where a reasonable basis exists for CMS to make a finding that comports with the regulation’s requirements.  Letantia Bussell, M.D., DAB No. 2196 at 12-13 (2008). 

Petitioner is a physician’s assistant practicing in the State of Georgia who was supervised by a physician, Dr. Kenneth Lazarus.  In his capacity as Dr. Lazarus’ assistant Petitioner

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prescribed a range of drugs to patients.⁴  These drugs included controlled substances that act as central nervous system depressants.  CMS alleges that Petitioner engaged in a pattern or practice of prescribing these depressants to individuals who were receiving large doses of opioids prescribed by Dr. Lazarus.  It asserts that the combination of opioids and other central nervous system depressants prescribed by Petitioner posed dangers to patients and could be lethal.  CMS alleges that Petitioner was heedless of these dangers.  It alleges that there are instances in which Medicare beneficiary patients of Dr. Lazarus and Petitioner suffered overdoses from the drugs that they prescribed.  

CMS contends additionally that in several instances Petitioner did not alter his prescriptions to patients even though he was aware that they were consuming illicit substances, non-prescribed opioids, or alcohol.  CMS argues that Petitioner’s failure to engage patients about their use of non-prescribed or illegal drugs shows that Petitioner was indifferent to the consequences of his patients’ consumption of large quantities of central nervous system depressants. 

Furthermore, CMS asserts that, in one instance, Petitioner prescribed a sedative, Ambien, to a Medicare beneficiary who was receiving the drug Suboxone, despite the beneficiary having signed an agreement stating that combining Suboxone with sedatives may have adverse and even fatal consequences. 

The evidence supports CMS’s assertions.  It establishes a reasonable basis for CMS to conclude that Petitioner engaged in a pattern or practice of prescribing drugs that threatened the health and safety of Medicare beneficiaries. 

Petitioner’s prescriptions to his patients often included drugs known as benzodiazepines.  CMS Ex. 7 at 2.  Benzodiazepines are depressants that produce sedation and hypnosis, relieve anxiety and muscle spasms, and reduce seizures.  CMS Ex. 67 ¶ 38; CMS Ex. 46 at 59.  The most common benzodiazepines are the prescription drugs Valium, Xanax, Halcion, Ativan, and Klonopin.  CMS Ex. 46 at 59. 

Concomitant consumption of opioids such as Codeine and Oxycontin and benzodiazepines can be dangerous, with consequences that may include extreme sleepiness, respiratory depression, coma, and death.  CMS Ex. 11 at 15; CMS Ex. 12.  The United States Food and Drug Administration (FDA) requires manufacturers of opioids and benzodiazepines to put a “black box” warning on labels that identifies the serious risks of harm resulting from combining the two classes of drugs.  CMS Ex. 12.  The FDA tells prescribers of medications that combining opioids and benzodiazepines

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should be limited only to those patients for whom alternative treatment options are not working.  If prescribed with opioids, prescriptions for benzodiazepines should be for lower doses than otherwise indicated.  Id. 

The Centers for Disease Control and Prevention (CDC) has issued guidance that is consistent with FDA findings.  The CDC recognizes that combining opioids and benzodiazepines puts patients at risk for suffering a fatal overdose.  CMS Ex. 11 at 15.  For this reason, the CDC recommends that benzodiazepines and opioids should not be prescribed together whenever possible.  Id. at 34. 

Other medications prescribed by Petitioner included drugs such as muscle relaxants that cause sedation and depress the respiratory system.  Using these drugs along with opioids can cause oversedation and blunt the instinct to breathe.  CMS Ex. 67 ¶ 38; CMS Ex. 54 at 4. 

Petitioner often prescribed benzodiazepines to Medicare beneficiaries who were receiving opioids at the same time.  A review of 101 beneficiaries who were Petitioner’s patients establishes that 79 of them (about 78 percent) to whom Petitioner had prescribed a benzodiazepine were simultaneously receiving opioids.  CMS Ex. 7 at 2.  Petitioner also frequently prescribed muscle relaxants to beneficiaries who were receiving opioids.  That was the case with 132 of 144 beneficiaries whose records were reviewed (almost 92 percent).  Id. 

CMS concluded reasonably that Petitioner engaged in a pattern or practice of prescribing benzodiazepines and muscle relaxants to Medicare beneficiaries who had also been prescribed opioids.  That is established by the high percentage of beneficiaries receiving opioids to whom Petitioner prescribed additional central nervous system depressants.  CMS additionally determined reasonably that this pattern or practice put beneficiaries at risk of sustaining respiratory depression, coma, or even death and that represented a threat to beneficiaries’ health and safety.  That was made evident by the FDA warning and by the CDC findings.  

CMS’s determination finds additional support from a review of the care that Petitioner provided to three Medicare beneficiaries.  Each of the three beneficiaries was admitted to a hospital with a diagnosis of a likely overdose.  CMS Ex. 37 at 978-983; CMS Ex. 39 at 606, 616-618; CMS Ex. 40 at 314.  Petitioner’s supervising physician had prescribed dangerously high quantities of opioids to each of these beneficiaries.  CMS Ex. 67 ¶¶ 42-43.  These individuals were in danger of experiencing overdoses even without the prescription of additional central nervous system depressants.  Notwithstanding, Petitioner prescribed central nervous system depressants to each beneficiary.  CMS Ex. 37 at 333; CMS Ex. 39 at 2-4; CMS Ex. 40 at 13, 20.  It is fair for CMS to conclude that his prescriptions made a very dangerous situation even more so.  CMS Ex. 67 ¶¶ 40-43. 

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Morphine milligram equivalent (MME) is a standardized formula that the CDC designed as a way of comparing the strength of one opioid to another and of determining the dosage of opioids that a patient is receiving.  MME converts dosages of various opioids to equivalent quantities of morphine.  CMS Ex. 10; CMS Ex. 68 ¶ 14.  The conversion of other opioids to MME enables one to determine the strength of any opioid dosage that is administered to a patient. 

Prior to 2018, CMS used an MME per day of 120 as a threshold to determine whether a beneficiary was receiving a quantity of opioids that indicated potential overuse.  CMS Ex. 21 at 3.  In 2018 CMS dropped the MME overuse indicator to 90.  CMS Ex. 11 at 18; CMS Ex. 22 at 2. 

Individuals who consume opioids at a high MME level are at risk for overdose and adverse consequences including death.  CMS Ex. 23 at 1, 3, 5.  The CDC finds that patients with dosages of 50 to 100 MME/day have up to a 460 percent increased risk of opioid overdose as compared with patients who are receiving dosages of up to 20 MME/day.  CMS Ex. 11 at 25.  The risk of overdose increases sharply as the dosage of opioids increases.  Id. 

The three patients to whom Petitioner prescribed central nervous system depressants had MME/day levels ranging from 160 to 285.  CMS Ex. 67 ¶¶ 41-42. 

CMS offered additional evidence to show that several of Petitioner’s patients had urine drug sample results that Petitioner was aware of and that demonstrated that the patients had consumed non-prescribed opioids, illicit drugs, or alcohol.  CMS Ex. 67 ¶¶ 57-67.  In multiple instances Petitioner failed to address this issue with his patients, nor did he adjust the prescriptions that he had provided to them.  Id.  This failure by Petitioner to address his patients’ substance abuse provides an additional basis for CMS to infer that Petitioner was prescribing drugs without paying heed to the possibility that what he prescribed posed a threat to his patients’ health and safety.  42 C.F.R. § 424.535(a)(14)(i)(H). 

Additionally, CMS offered evidence establishing that Petitioner prescribed Ambien, a sedative, to a Medicare beneficiary who was receiving Suboxone, a central nervous system depressant.  That, even though the beneficiary and Petitioner signed an agreement stating that combining Suboxone with a sedative may result in accidental overdose, over-sedation, coma, or death.  CMS Ex. 75 at 1; CMS Ex. 76 at 1.  CMS cites this episode as providing additional proof of Petitioner’s carelessness when prescribing central nervous system depressants to beneficiaries.  I find that to be a reasonable conclusion. 

I have considered Petitioner’s arguments in opposition to CMS’s determination.  I conclude that they, and the evidence that Petitioner relies on, are insufficient to show that

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CMS acted arbitrarily in determining to revoke Petitioner’s Medicare enrollment and billing privileges. 

Petitioner did not challenge CMS’s evidence establishing what he prescribed and to whom.  Petitioner argues, however, that his prescription practice was consistent with the applicable standard of care.  In the cases of the three beneficiaries who were hospitalized with diagnoses of overdoses, Petitioner asserts that he provided all three beneficiaries with care that is within the standard of care.  As support for this assertion Petitioner relies on the testimony of Mitchell Nudelman, M.D., J.D.  P. Ex. 4. 

Dr. Nudelman asserts repeatedly that Petitioner’s prescription practice was within the applicable standard of care and he avers explicitly that this was so with respect to individual beneficiaries.  However, Dr. Nudelman does not define the standard of care nor does he cite any sources to support his contention.  He does not address the CDC and the FDA warnings about combining opioids with central nervous system depressants.  Nor does he explain how prescribing central nervous system depressants to beneficiaries whose MMEs/day were as high as these beneficiaries manifested was consistent with the CDC guidelines. 

Dr. Nudelman attempts to explain Petitioner’s prescription of central nervous system depressants to these beneficiaries by asserting that they were all long-term users of high levels of opioids and central nervous system depressants who had not suffered any significant ill effects from their use.  P. Ex. 4 at Appendices B-E.  He attempts to justify continued prescription of these drugs to the patients both by asserting that they tolerated them and that they had resisted being weaned off them.  That may be so but that does not explain how continued prescription of a potentially dangerous combination of drugs is consistent with the FDA and the CDC guidelines or with standards of care. 

Petitioner’s remaining defense consists of his assertions that CMS acted arbitrarily.  

Petitioner argues that CMS’s determination is arbitrary and an abuse of discretion because CMS allegedly did not consider and give due weight to all factors stated at 42 C.F.R. § 424.535(a)(14)(i) and (ii).  Petitioner Wallace Green, PA-C’s Pre-hearing Brief and Motion to Admit New Evidence (Petitioner’s brief) at 2-4.  The gravamen of Petitioner’s argument is that in determining to revoke an individual’s Medicare enrollment and billing privileges CMS must consider all factors enumerated under 42 C.F.R. § 424.535(a)(14)(i)(A)-(H) and (ii)(A)-(C) and not just some of them. 

Petitioner incorrectly reads the regulation.  

Subparts (i) and (ii) of the regulation are independent of each other.  CMS need not find that a basis for revocation exists under both subparts to revoke.  It may revoke if a basis exists under subpart (i) or if a basis exists under subpart (ii).  

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Subpart (i) explicitly addresses a pattern or practice of prescriptions that is abusive or poses a threat to the health and safety of beneficiaries.  Subpart (ii) addresses a pattern or practice of prescriptions that fails to meet Medicare requirements.  This subpart has a broader reach than has subpart (i).  A pattern or practice of prescriptions may fail to meet Medicare requirements for a host of reasons not necessarily related to the health and safety of beneficiaries.  That is made evident by factors (A) through (C) of that subpart, which do not directly include risks to beneficiary health and safety. 

42 C.F.R. § 424.535(a)(14)(i) does not require CMS to establish proof relating to all the factors (A) through (H) that are listed under that subpart.  It requires only that CMS “considers” those factors.  Evidence relating to any of the factors, including the catchall factor (H), will justify revocation if it establishes CMS’s determination to be reasonable. 

Here, CMS obtained evidence that addresses both factors (C) and (H).  Factor (C) directs CMS to consider whether:  “the physician or eligible professional has prescribed controlled substances in excessive dosages that are linked to patient overdoses.”  The evidence shows that on numerous occasions Petitioner prescribed central nervous system depressant drugs to individuals who were also prescribed opioids (and in some instances very large amounts of opioids).  Guidance published by both the FDA and the CDC makes it plain that depressant medications should not generally be prescribed to patients who are receiving opioids because that combination of medications is linked to dangerous effects, including coma and death.  Any prescription of a depressant medication such as benzodiazepines to a patient who is receiving opioids may be considered as “excessive” absent carefully documented justification of the unique circumstances that qualify the patient for the prescription. 

Factor (H) directs CMS to consider any other evidence that may be relevant.  Here, CMS considered evidence that addressed Petitioner’s pattern of prescribing central nervous system depressant drugs to beneficiaries who were receiving opioids, his prescriptions of depressants to patients who were receiving opioids at levels that greatly exceeded the maximum recommended MME/day, and his failure to address evidence that patients were consuming non-prescribed medication and illegal drugs.  This evidence is relevant to CMS’s determination that Petitioner is untrustworthy to provide care to beneficiaries.  It was not only reasonable for CMS to consider it, but the evidence renders CMS’s determination to be reasonable. 

Petitioner asserts that the experts whose testimony CMS offered, Dr. Patterson and Mr. Risko, lack the requisite knowledge to opine about Petitioner’s practice.  Petitioner’s brief at 5-6; see CMS Ex. 67; CMS Ex. 68.  I have already discussed Dr. Patterson’s qualifications and need not reiterate them here except to say that her background in internal medicine and her experience as a medical director for Medicare contractors provide solid support for her opinions. 

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The thrust of Petitioner’s argument objecting to the opinion of Mr. Risko is that he is unqualified to render an opinion about the risks associated with prescribing benzodiazepines or muscle relaxants to individuals who have been prescribed opioids.  Petitioner contends that Mr. Risko is unqualified because he has not acquired experience as a clinical pharmacist specializing in compounding or providing drugs that are used in pain management, addiction, psychiatry, neurology, or the other medical issues that Petitioner’s physician supervisor treated.  Petitioner’s brief at 5-6. 

I am not persuaded by this argument.  Mr. Risko has an extensive background – decades, in fact – as a licensed pharmacist.  CMS Ex. 68 at 11-14.  Moreover, Mr. Risko did not base his opinion about the risks arising from combining opioids with other central nervous system depressants solely on his experience as a pharmacist.  He based his opinion on authoritative guidelines issued by the FDA and the CDC.  CMS Ex. 68 at 3-5. 

Petitioner’s central argument is that CMS arbitrarily relied on an “incurably flawed” review of Petitioner’s prescriptions that misapplied the CDC guidelines.  Petitioner’s brief at 6-11.  As support, Petitioner relies on Dr. Lynch’s opinion, as expressed in his affidavit, that Petitioner (and his physician supervisor) were not excessively prescribing opioids or other central nervous system depressants but were, in fact, assisting patients who were suffering from long-term opioid addiction.  Petitioner’s brief at 11-13; P. Ex. 1. 

Petitioner’s argument hinges on his contentions that CDC guidelines are advisory and not mandatory and that they were intended to guide general practitioners and not pain or opioid addiction specialists.  According to Petitioner, his supervisor and he were not bound by the guidelines but could use their professional judgment acquired as pain management specialists to treat patients who suffered from unique conditions and from long-term addiction to opioids. 

There are obvious problems with Petitioner’s contentions.  Although the CDC guidelines do not carry the force of law, they certainly address significant concerns about the risks and hazards associated with combining prescriptions for opioids with prescriptions for other central nervous system depressants.  Petitioner has offered no evidence to suggest, much less prove, that the CDC and the FDA are wrong in concluding that combining opioids with other central nervous system depressants may put patients at risk for serious consequences, including coma and death.  Petitioner has not shown why CMS’s reliance on the CDC and the FDA guidance is unreasonable or arbitrary. 

Petitioner has not proven why those of his patients who were receiving high dosages of opioids and to whom Petitioner prescribed benzodiazepines or muscle relaxers were any less at risk for adverse consequences by virtue of their status as chronic pain sufferers or long-term opioid users.  In fact, Petitioner’s argument and contentions do not cite to any vindicating sources.  See Petitioner’s brief at 6-11. 

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The thrust of Dr. Lynch’s opinion is that Petitioner prescribed benzodiazepines to only a small percentage of his patients who were receiving opioids – 3.4 percent, according to Dr. Lynch.  P. Ex. 1 at ¶ 13.  He suggests that such a small percentage of overall patients receiving both types of central nervous system depressants hardly amounts to a pattern or practice of prescribing such medications.  Additionally, Dr. Lynch opines that Petitioner’s patients who were receiving opioids had an average MME of 64.25, well below the maximum MME advised by CDC guidelines.  Id. at ¶ 16.⁵ 

Dr. Lynch’s opinion is unpersuasive.  He premises his assertion that Petitioner prescribed central nervous system depressants to only a small percentage of patients who were also receiving opioids on Petitioner’s overall practice and not on the Medicare beneficiaries that Petitioner treated.⁶  Dr. Lynch’s contention does not respond to CMS’s determination that Petitioner prescribed benzodiazepines or muscle relaxers to a high percentage of his patients who were Medicare beneficiaries and who had been prescribed opioids.  CMS Ex. 7 at 2. 

Dr. Lynch opines that Petitioner did not “operate with any maleficence motivation in the treatment of his patients.”  P. Ex. 1 ¶ 19.  Petitioner’s motivation is not at issue in this case.  His prescription practices are.  Nothing in Dr. Lynch’s opinion establishes that CMS’s determination is unreasonable or arbitrary. 

Petitioner argues that CMS’s determination to revoke Petitioner’s Medicare enrollment and billing privileges deprives him of his constitutional right to due process.  Petitioner’s brief at 13-14.  I do not have authority to address Petitioner’s due process argument.  CMS’s determination in this case is consistent with regulations, as I have explained. 

2. 2. Placing Petitioner on the Preclusion List

CMS placed Petitioner on its Preclusion List, an action that effectively bars him from receiving reimbursement for services provided for or on behalf of any federally funded healthcare program.  In doing so, CMS relied on 42 C.F.R. § 422.2.  This section authorizes placing an individual on the Preclusion List, with exceptions that do not on their face apply here, if that individual’s Medicare participation is currently revoked, if the individual is currently under a reenrollment bar, and if CMS determines that the underlying conduct that led to revocation of that individual’s participation is detrimental

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to the best interests of the Medicare program.⁷  CMS considers the following factors to determine whether putting an individual on the Preclusion List is in the best interests of the Medicare program:  (A) the seriousness of the conduct underlying the revocation of the individual’s Medicare enrollment and billing privileges; (B) the degree to which the individual’s conduct could affect the integrity of the Medicare program; and (C) any other relevant evidence.  42 C.F.R. §§ 422.2, 423.100. 

CMS asserts that evidence relating to the seriousness of the harm potentially caused by Petitioner’s prescription practices and the dangers that such practices pose to the integrity of the Medicare program are sufficient to justify placing Petitioner on the Preclusion List.  I conclude that CMS acted reasonably in reaching this conclusion.  Of particular concern in this case is that Petitioner regularly prescribed central nervous system depressants to beneficiaries who were receiving opioids, a combination that could prove to be lethal for these beneficiaries. 

Petitioner has offered neither evidence nor argument specifically addressing CMS’s determination to place him on the Preclusion List. 

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Endnotes

¹  CMS Ex. 40 is a voluminous document that CMS filed in parts, identified as Part 1 through Part 6. 

²  P. Ex. 3 is another voluminous document that Petitioner filed in parts, identified as Part A through Part J. 

³  The Standing Order governing the management of this case directs a party desiring to cross-examine witnesses to file a written request to conduct cross-examination.  Standing Order at 5-6, ¶ 9.  Neither party did so. 

⁴  Georgia law permits a physician’s assistant to prescribe certain classes of drugs including some controlled substances.  Ga. Code Ann., § 43-34-103(e.1).  There is no dispute that Petitioner was authorized by law to prescribe the drugs that are at issue in this case. 

⁵  Dr. Lynch did not address the CDC findings that an MME of 50 per day or greater is associated with increased risks to patients’ health and safety.  CMS Ex. 11 at 25. 

⁶ Dr. Lynch does not offer any explanation of the methodology he used to calculate his estimate of the percentage of Petitioner’s patients to whom Petitioner prescribed central nervous system depressants. 

⁷  42 C.F.R. § 423.100 restates these criteria.