I recently read an interesting but I think incomplete and less than pragmatic paper in the American Economic Review by Fang and Gong. In that paper they use Medicare Part B claims data to advance what they argue is a good first pass claims fraud detection methodology. They seek to identify individual National Provider Identification (NPI) numbers which perform more than 100 hours of billable work per week over the course of a year of claims. They then contend that these individuals are likely fraud investigation targets. From there, they build an interesting model that looks at time utilization and cost.
I have several major objections to this paper. The first is a pragmatic objection which I think renders the data as they interpreted it to be less than useful. The second objection is more of a critique of their methodological choices to model fraud. But first, I want to highlight something I wrote when the Center for Medicare and Medicaid Services (CMS) started to release Medicare billing data:
- Claims rolling up to a provider’s NPI or Medicare ID. Non-MD/non-D.O. clinicians such as Certified Nurse Practitioners, Physician Assistants, Master and Doctorate level Physical Therapists etc. often will roll their billing up to a doctor’s Medicare billing number. This means we can’t do a simple time management bullshit detection study based solely on “This provider is claiming he is doing 17 Medicare Part B procedures a day. Each of these procedures takes 30 minutes… IMPOSSIBLE”. That type of first level analysis might identify odd situations, but most will be explained by seeing three or four CRNPs/PAs doing most of the work that the doctor than bills for.
- Medicare Advantage is not in this data set. Some regions have lots of Medicare Advantage enrollment. Others don’t Some docs have a lot of Medicare Advantage patients. Others don’t. We can’t generalize too well to the entire Medicare population from the CMS data set.
- No way to determine medical neccessity/particular skill. This is pure counting data, it is not quality data…
Fong and Gong only look at the provider NPI. They neglect to examine the possibility that there is significant number and time of services being performed by non MD/DO providers who are performing services incidental to the supervising physician’s practice and billing under the MD/DO NPI.
There is nothing in the paper that addresses non-MD/DO providers rolling up their billing to an MD/DO NPI. This is quite common and allowed. Some master’s level clinicians in some states routinely bill independently. This information is captured in this study and noted in footnote 5. However many non-MD/DO providers will bill via their supervising MD/DO. The Wall Street Journal noted this arrangement in 2014 for an orthopedic practice in the middle of an article about the problems of analyzing outliers by Excel without contextual knowledge. The physical therapists that practiced underneath the surgeons billed with the surgeon’s NPI. This is legal and common. I think this paper is missing the non MD/DO provider universe as implied in Footnote #6;
For expositional simplicity, we will refer to all individual providers as physicians even if a small fraction of them are nurses or physician assistants
Nowhere in the paper did I see the phrase “incidental” or “modifier code” or any other indicator that a significant portion of primary care and first level specialty work is now being performed by non-MD/DO providers who routinely roll up their billing to an MD/DO provider.
The Office of Inspector General at CMS has examined very high implied time billing practices in the past. What they have found is the services were being legitimately performed although at times they were being performed by clinicians who were not authorized by either license or law to perform a set of services as services incidental to the MD/DO who supervised them. Here the better assumption is that this is either waste or abuse rather than deliberate fraud unless there is extraordinary evidence to argue for fraud.
If there is limited to no inclusion of master’s level clinician service rendering then the analysis performed by Fang and Gong will lead to numerous false positives which renders their tool an inefficient use of time and resources to detect actual incidents of fraud.
My second major concern with this paper is their modeling choice of time utilization.
I think it is flawed and biases their estimates of potentially fraudulent activity. If we assume that there is significant fraud via overclaiming of time, then the methodology that is used in this paper which the authors claim is conservative will overstate the hours worked. Actual fraud will go undetected while legitimate and appropriate services will be flagged.
The authors methodology:
Our idea is to use the time requirement for timed codes described above to estimate the time requirement for all other codes. In order to do this, we construct the expected time needed for each code based on the “typical time needed” suggested by the AMA guideline.10 This is important because the actual time to furnish a service code may vary both across and within physicians. We construct the “expected time needed” from the “typical time needed” as in AMA guideline as follows. Assuming the time needed follows a uniform distribution, we take the simple average of the minimum and maximum time allowed for each code to get the expected time. Specifically, some codes may have an explicit range of time needed, such as “5-10 minutes of medical discussion.” For such codes, the expected time needed is simply the average of the lower and upper bounds. For codes that do not have such a range, physicians are supposed to file the code whose typical time needed is closest to the actual time spent. For example, between codes 99202 and 99203 as described in Table 1, a physician who spent 23 minutes should file the code 99202 instead of 99203. Following this logic, the expected time needed we will assign to HCPCS codes 99201 through 99205 are 7.5, 20, 31.25, 45, and 60 minutes, respectively. To see this, consider HCPCS code 99201 for example. Note that physicians who spends 0 to 15 minutes with a new patient is supposed to file HCPCS code 99201 if they follow the AMA guideline. Thus, under the plausible assumption that the actual time spent with patients follows a uniform distribution, the simple average of the minimum (0 minute) and maximum (15 minutes) time allowed for filing 99201 is 7.5 minutes
We know in other fields (auto mechanics, HVAC repair) there is a significant disparity between the time that is recommend for an action to occur and how long it takes for a skilled individual who is optimizing for revenue maximization to complete the task. Under most circumstances, the performance time is significantly less than the recommended time. I would have a hard time believing that some MD/DO providers who have no one else rolling claims up to them have not adapted a system where they consistently perform time recommended tasks near the bottom of the recommended range.
If we are to assume that a provider is intentionally attempting to maximize Medicare Part B revenue through aggressive billing for services then this metric is optimizing on cost per service. I do not think that is the appropriate metric. Instead the greatest constraint is physician time so the relevant unit of analysis should not be revenue per procedure code but revenue per procedure code per minute. For instance, in 2014, the National Payment Amount for 99201 is $43.35 at a non-facility. The per minute rate ranges from $43.35 for a one minute visit to $2.89 per minute for a fifteen minute visit. A 7.5 minute visit averages $5.78. 99202 has a national payment amount in 2014 of $74.51. At a sixteen minute length of service, this is a rate of $4.65 per minute. Using the author’s estimates $3.72 per minute is the estimated revenue per minute for 99202.
The clear incentive if the physician is actively attempting to maximize revenue with a strong time constraint is to minimize the amount of time spent with a patient and maximize the number of patients that are seen. An estimated 99201 visit of 7.5 minutes is more valuable on this metric than an author estimated 99202 visit of 20 minutes if the provider is able to see more patients. At this point, it is a clinical and pragmatic need to examine how many patients are seen and how often are they seen.
These pragmatic concerns of not addressing non-MD/DO billing as well as the wrong choice and thus the wrong modeling of provider revenue considerations as a function of time instead of a function of service codes leads me to believe that what should have been an interesting paper is not actively advancing pragmatic knowledge of the field.
rikyrah
There you go…. Telling the truth Mayhew.
Thanks.
They are always trying to manipulate stuff for their evil purposes.
DAVID ANDERSON
@rikyrah: not evil, just not pragmatic research
Sab
That approach would blow things up for my dad’s gerontologist, who is a wonderful doctor.
Sab
Don’t all gerontology practices involve a combination of social workers and nurse practitioners under the umbrella of an md?
Raphael Kearns
In the past 18 months I have visited a number of Specialists and can speak to the first part of your post. I have seen my local Dermatologist, who employs 3-4 physician assistants. I have never seen the supervising Dermatologist, which is fine by me, I’m quite happy with the service I’ve received. This PA diagnosed a basal cell CA, biopsied it and referred me to a specialist for a MOH’s procedure.
After the procedure I returned to the original office for quarterly full body exams. On the first visit another basal cell was identified and diagnosed by biopsy. This was in a location that was able to be removed via traditional procedure, which the PA then excised and repaired. This particular procedure took about an hour. I’m sure this office would be in danger of being identified erroneously just by the matter of employing many non MD/DO’s.
MomSense
David I am going nuts listening to Republicans and media pundits talk about how much the ObamaCare increases were and how in some markets there is only one insurer without talking about how they sabotaged rates, co-ops, and small insurance companies by gutting risk corridors.
I feel like I’m taking crazy pills listening to them just lie unchecked about the ACA.
Victor Matheson
Here’s another example. There are over 4,000 genetic counselors in the US. Most of them bill under a MD such as a geneticist, oncologist, or maternal fetal medicine or pediatric specialist. In most states they are prohibited for billing directly for their services because they don’t have an appropriate Medicare billing code.
Thus, there are a lot of geneticists who appear to be doing massive overtime but actually work in a clinic with a couple of genetic counselors.
Hard to believe AER would make such a glaring error. That is worth an immediate letter to AER.
Victor Matheson
@rikyrah: I second Mayhew. This is not evil. This is just a mistake that comes from people in one profession attempting to study another profession without knowing some of the practical aspects of the target of the study.
I should point out that in my experience there are a lot more medical doctors playing economist than economists playing medical doctor (as was the case here). If I had a dime for every MD who I have heard say, “I am a doctor and I think the ACA is destined for failure because…” If you are a doctor your expertise is medicine not health economics. And your opinions are not necessarily any better informed about the ACA than anyone else.
Similarly, I once served on a panel about stadium subsidies with the mayor of Salt Lake City (a good choice due to the 2002 Olympics), a executive from FIFA (another useful although potentially biased viewpoint), and Boris Becker (?????). Being good at serving a tennis ball at 120 MPH in a publicly financed tennis stadium doesn’t mean you know anything about financing tennis stadiums.
Ben Vernia
A couple of points from an attorney who spends a fair amount of time handling fraud cases involving health care providers:
First, Medicare/Medicaid fraud seems to break down on what I’ll call blue collar/white collar lines. The blue collar fraud consists of Medicare “mills” where few, if any, beneficial services are performed, and the enterprise exists to monetize Medicare/Medicaid IDs as quickly as possible. Although overbilling of the type described here certainly occurs, these short-lived enterprises try to run up the bill with multiple procedures, not just overbill for a physician’s time with the patient.
The white collar fraud occurs at otherwise normal health care providers, and involves playing at the margins. Overbilling for time can occur there, too, but I think it’s much more common to find unnecessary procedures, upcoding (submitting a claim for a higher-reimbursement procedure related to the one actually provided), and kickback, self-referral, and similar complicated issues.
I would think that the approach described could be used as one way to conduct triage of providers, with a secondary, more manual screening out (or analysis) of those with subordinate caregivers, etc.
One other point: regarding Medicare Advantage — since MA is capitated, what relevancy would those claims have in the analysis they are conducting?
Raphael Kearns
@Victor Matheson: This is certainly the case in the Congress. The representative who is the head of the committee that is tasked with the destruction of the ACA just happens to be my representative. Rep. Michael Burgess an Ob/Gyn physician. He is completely clueless.
Electing a bunch of physicians to Congress is the fastest way to destroy our democracy.
David Anderson
@Ben Vernia:
The approach IF it already includes consideration for rolled-up non MD/DO provider billing is a useful BS check. But this paper is not advancing a good bullshit check as it does not include appropriate filters for known clouding factors. HHS OIG has limited resources and having them chase down CRNP/PA roll-up billing is a complete waste of their time.
As for Medicare Advantage, the issue is that in regions with low FFS penetration, this metric will detect very low plausible fraudulent activities as most Medicare billing is happening in Part C not FFS. Pittsburgh would be like this. It would make the region look low fraud when it is just measuring Part C penetration.
Exurban Mom
Your objections seem extremely well thought out. Did this paper get peer reviewed? If so, this is poor work on the editors’ part. (I’m not familiar with journals in your specialty.)