Medicare Coverage of Routine Screening for Thyroid Dysfunction (2003)

The Committee was asked to consider, in addition to the possible benefits, the cost to the Medicare program of coverage of thyroid stimulating hormone (TSH) screening. This cost is dependent on the number of people screened and changes in the use of resources that result from screening. This chapter begins with an examination of the effect that Medicare coverage has had on the use of other preventive services and identifies factors from that experience that may be relevant to screening with TSH for thyroid dysfunction. The impact of these factors is assessed in conjunction with additional data from a study of thyroid disease among Medicare beneficiaries and an analysis of Medicare claims data to provide estimates of the number of beneficiaries who would be screened. Finally, an economic model is used to estimate costs per beneficiary screened.

There are limited historical data that can be used to ascertain how much of an effect Medicare coverage of various preventive services has had on the use of those services. The Centers for Disease Control and Prevention tracks use of preventive services through its Behavioral Risk Factor Surveillance System (BRFSS) (Centers for Disease Control and Prevention, 2002). After these services are covered, their use also can be tracked through the use of Medicare claims data (McBean, 2002). Tables 5-1A through 5-1C show the BRFSS data for influenza and pneumonia immunizations, mammography, and Pap smears, the only preventive services covered by Medicare for which BRFSS data are available.

Coverage for preventive services has been accompanied by only gradual increases in the use of those services. In the case of pneumococcal vaccine, for example, by 1993 only 27.8 percent of the population age 65 and older reported that they had ever been immunized even though Medicare has covered the service since 1981. This proportion then nearly doubled between 1993 and 1999 and has continued to increase. The U.S. General Accounting Office (GAO) has found that Medicare coverage by itself has not been enough to promote use of preventive services by most beneficiaries, and additional efforts—working to increase demand or remove other barriers to access to services—are necessary to increase their use (GAO, 2002). A large body of work on theories and behavioral models

has addressed the question of determinants of utilization of clinical preventive interventions in primary care (Elder et al., 1999).

Demand is a key factor in service use. If there is little interest in or awareness of the service by the patient (or the patient’s physician), coverage will make little difference. This appears to have been the case for pneumococcal vaccine—significant educational and outreach programs were used to increase immunization rates (GAO, 2002). The close correlation between the usage of services in the population over age 65 and in younger age ranges suggests that demand for preventive services by Medicare beneficiaries parallels more general trends in society.

Medicare coverage may be an important factor in the use of a service, but the effect is indirect. Strictly speaking, Medicare coverage policy only assures that Medicare payment for a particular service is available. A cost barrier is removed for those Medicare beneficiaries for whom the cost of the test would be a barrier to its use. If these beneficiaries encounter barriers in addition to the cost of the service, payment will not enable them to make use of the service unless those barriers are also overcome. The primary economic barrier to the use of preventive services may not be the cost of the service but the costs of other activities related to obtaining the service.

Access to health care services is also heavily influenced by factors that are not related or only indirectly related to payment for services. For example, significant differences exist in the use of Medicare-covered preventive services among racial and ethnic groups (GAO, 2002); these differences are partially

related to the degree of trust held in providers and the health care system (IOM, 2002). In some states, the lack of easily available Medicare providers has limited the use of preventive services (GAO, 2002). The problem of availability of providers may be geographical remoteness in rural areas or may be a reflection of the lack of material resources in communities too poor to provide adequate health care facilities. Factors with important positive influence on access to care include social support networks that encourage patients to seek care and support; the ability of patients to leave home or work to obtain care; well-developed transportation systems; low crime rates; high literacy rates; providers with compatible language and culture; and a regular provider and site of care (IOM, 2002). Even when patients have good access to health care services, the delivery system may need to be changed so that preventive services can be easily offered, accepted, and delivered within the usual patterns of care (GAO, 2002).

Finally, coverage may not have a significant impact on the use of a service if the service is easily available without coverage. If it is not expensive, a patient may pay for the service himself. A number of “Medigap” supplemental insurance plans cover preventive services. Providers are often motivated to offer free screening as a means of identifying new patients in need of services for which the providers would be paid. Some screening tests are also used for diagnostic purposes, and the line between screening and diagnosis can often be blurred (McBean, 2002). If good alternative means exist for obtaining the service, a beneficiary may not take advantage of coverage or may substitute for the alternative by obtaining the service through Medicare coverage.

There is no direct evidence, such as surveys or pilot programs, of the level of interest or demand for serum TSH screening among Medicare beneficiaries or health care practitioners. Statements of expert opinion have been made on screening for thyroid disease, and a number of groups have published recommendations on the subject (Arbelle and Porath, 1999; United States Preventive Services Task Force, 1996), but their conclusions have differed. Even without such disagreements, the acceptance of recommendations into common practice is a long and complex process (IOM, 1990).

To estimate the use of serum TSH screening with Medicare coverage, the Committee needed two types of information: the size of the population covered and the proportion of the potential screening population likely to be tested. Creation of a preventive services benefit for TSH screening should only affect directly those Medicare beneficiaries who do not already have an indication for testing. To estimate the size of the potential screening population, it is necessary to count only those beneficiaries who would not already be covered for serum TSH testing under current Medicare coverage policy. That group would include not just beneficiaries with known thyroid disease but also those with conditions

believed to be affected by thyroid disease. The proportion of beneficiaries who receive serum TSH tests among those who are without known thyroid disease but currently covered for serum TSH testing could provide a plausible estimate of the proportion tested out of the potential screening population.

On November 23, 2001, the Federal Register published a Medicare National Coverage Decision for thyroid testing (Centers for Medicare and Medicaid Services, 2001). According to this document (page 58853);

• Distinguish between primary and secondary hypothyroidism;

• Confirm or rule out primary hypothyroidism;

• Monitor thyroid hormone levels (for example, patients with goiter, thyroid nodules, or thyroid cancer);

• Monitor drug therapy in patients with primary hypothyroidism;

• Confirm or rule out primary hyperthyroidism; and

• Monitor therapy in patients with hyperthyroidism.

This is a very broad range of clinical conditions. The document lists approximately 200 ICD-9-CM codes for diagnoses that would establish medical necessity for TSH testing. (These are listed in Appendix C.) Although many of these diagnoses are obscure, a large number describe conditions that are common in the Medicare population, including diabetes, hypertension, hyperlipidemia, anemia, dementia, cardiac arrhythmias, palpitations, insomnia, fatigue, weight change, and constipation. This would indicate that many Medicare beneficiaries already have an indication for TSH testing and, therefore, should be unaffected by coverage of TSH screening as a preventive services benefit.

The Committee used two sources of data to identify which Medicare beneficiaries in the population do not already have an indication for TSH testing. The first was the New Mexico Elder Health Survey, a population-based sample of Medicare beneficiaries in Bernalillo County (Albuquerque), New Mexico (Lindeman et al., 1999). The second was an analysis of Medicare claims data.

The New Mexico Elder Study used Medicare enrollment data to select and recruit 883 Medicare beneficiaries for an interview and examination, including TSH and other diagnostic tests. Nearly half of this group was Hispanic, a proportion much larger than the national Medicare population, which is less than 3 percent Hispanic (U.S. Department of Health and Human Services, 1998); none were African American. Because the prevalence of some common conditions that are indications for TSH testing, particularly diabetes, is significantly different in the Hispanic population than in the general Medicare population, we analyzed the 469 non-Hispanic subjects (non-Hispanic whites are about 85 percent of the national Medicare population) (U.S. Department of Health and Human Services, 1998) separately from the 414 Hispanic subjects.

We estimated the number of subjects who did not have an indication for TSH testing under current Medicare coverage policy by removing from the sample those who appeared to have an indication for testing:

• Known thyroid disease: A history of thyroid disease or current thyroid medication use

• Hypertension: Systolic blood pressure above 160 mmHg, self-reported hypertension, or current antihypertension medication

• Current fatigue

• Weight gain or loss of more than 10 pounds in the past 6 months

• Hyperlipidemia: Serum cholesterol greater than 240mg/dl

• Insomnia

• Current hoarseness

• Arrhythmia on electrocardiogram or physical examination

• History of depression

• Anemia: Men with a hematocrit below 40,women with a hematocrit below 35

• Diabetes: Current diabetes medication or history of diabetes

• Current neurological problem

• Current chronic constipation

• Current tranquilizer use as evidence of anxiety or insomnia

After these subjects were removed from the sample, only 51 (11 percent) of the non-Hispanic subjects remained, having none of the above indications for TSH testing. Of the 51, 14 had not seen a physician in the preceding 6 months, making it less likely that they would be available for screening even if the benefit were available. We concluded that 8 percent (37 of 469) of the non-Hispanic white Medicare beneficiaries in the sample would be eligible and available for TSH screening. The subjects identified as likely candidates for screening were, on average, 2 years younger than the entire study population and more than twice as likely to be men. Because increasing age and being female are major risk factors for thyroid disease, the screening candidates should be at relatively low risk for thyroid disease.

Among Hispanic subjects, 46 (11 percent) remained, having none of the indications listed for TSH testing. Of the 46, 18 had not seen a physician in the preceding 6 months. We concluded that 7 percent (28 of 414) of the Hispanic Medicare beneficiaries in the sample would be eligible and available for TSH screening. The subjects identified as likely candidates for screening were also, on average, 2 years younger than the entire study population, but not significantly more likely to be men (57 percent versus 51 percent).

Analyzing Medicare claims data was the second method the Committee used to estimate the number of Medicare beneficiaries who would become eligible for TSH testing with the establishment of a preventive services benefit. A claim to Medicare for payment is generally required to present documentation that the service provided is medically necessary. This is usually done by submitting a diagnosis (and associated ICD-9-CM code) with the claim. When there is a coverage policy for the service, the diagnosis must be one accepted by the policy in order for the service to be covered and payment to be made.

We attempted to define the screening population by asking, “How many Medicare patients who have never submitted a claim containing a diagnosis with an indication for TSH testing see a physician in a given year?” Answering this question involved some cautions and complications in analysis. The answer could exaggerate the number of potential screening candidates because not all patient diagnoses are entered on claims. A further complication came from the need to limit the time period in which to search for relevant claims. Too short a period of looking back from the reference year would make it more likely that diagnoses will be missed. Too long an observation period will exclude too many beneficiaries who entered the program during the period for which claims are examined. There was also a question of how to approach a patient who had an indication for testing in the past that was transient. For example, a patient who reported constipation 2 years earlier may no longer have this problem in the reference year; testing in the reference year, assuming there were no other indications, would be

considered screening. However, if the patient received TSH testing as part of the evaluation of his constipation, the patient would not be a candidate for screening if the interval approved for screening was greater than the time since the last TSH test.

To perform this analysis, we created a cohort consisting of 5 percent of Medicare beneficiaries enrolled on January 1, 1997. Using physician and outpatient claims files for 1997, we then examined their submitted claims for diagnoses that are approved for TSH testing under current policy. We divided the diagnoses listed in Appendix C into three groups: (1) diagnoses of thyroid disease, (2) diagnoses of chronic or permanent conditions that would be persistent indications for testing, and (3) diagnoses of possibly transient conditions that would be short-term indications for testing. A patient was considered a candidate for screening in 1997 if he did not submit a claim containing one of the indications for testing and saw a physician whose specialty was general practice, family practice, or internal medicine (including subspecialties) that year; we considered these specialties to be the most likely to do testing for thyroid disease. This would be the potential population size for screening on an annual basis. To look at longer periods, we removed from the cohort all of the subjects in the first and second categories along with those in the third category who actually received a TSH test. We then looked at the claims data for the remaining subjects for 1998, applying the same criteria for potential screening candidates (this time with a 2-year testing interval) and removal from the cohort. This process was repeated for a total of 5 years.

Results from the claims data study are given in Table 5-2. Even when evaluated on the most liberal criteria—no indications for testing listed on claims for 1997 only—just 7.7 percent of beneficiaries would have been available for screening in that year. As was found in the New Mexico study, the potential screening population is younger and more heavily male, hence at lower risk for thyroid dysfunction. As the criteria for screening become stricter by looking for testing indications over a longer period and allowing more subjects to develop indications for testing over a longer screening interval, the potential screening population becomes even smaller, younger, and more likely to be male. With a 5-year

testing interval, looking in 2001 for all claims from 1997 to 2001, candidates for screening make up only 1.3 percent of the Medicare population; they are 55.3 percent male (compared to 42.5 percent male in the total Medicare population) and are, on average, 7.8 years younger than the average Medicare beneficiary. Fewer than 10 percent of these candidates for screening received testing for diabetes or cholesterol; if the remainder of this group were screened for these other conditions instead of being screened for thyroid disease, those who tested positive would have an indication for testing and no longer be considered candidates for screening. For the purposes of our estimates, we have taken the middle figure from Table 5-2, 2.7 percent, as the proportion of Medicare beneficiaries who will be available and newly eligible for serum TSH testing because of the implementation of a screening benefit.

To estimate the proportion of candidates of screening who would be tested, we looked at the population of beneficiaries enrolled in the Medicare program on January 1, 2001. From this group we identified those beneficiaries who (1) did not submit a claim in 2001 with a thyroid disease diagnosis, (2) had a physician visit with one of the specialties most likely to test for thyroid disease, and (3) submitted a claim in 2001 with a diagnosis recognized by current Medicare coverage policy as an indication for serum TSH testing. Of this group, 21 percent received serum TSH testing.

Combining these figures, we estimate that 0.6 percent (21 percent of 2.7 percent) of Medicare beneficiaries, 250,000 at the current population, would be screened if coverage were implemented. This is an imprecise estimate that is dependent on many factors. A short interval between screenings (1 to 2 years) would likely increase the number screened because fewer subjects would develop indications for diagnostic testing; a longer interval would have the opposite effect.

The estimate does not consider the effect of efforts to encourage serum TSH testing that may occur in conjunction with coverage for screening. Such efforts could also lead to “screening” among patients who already have indications for testing. We did not include any increases in testing among this group as being due to coverage for screening because such an effect is not specific to the change in coverage; it could occur in the absence of a change in coverage and as a result of any phenomenon that would encourage testing, such as higher payments or promotion of testing by advocacy groups.

In the absence of efforts to encourage testing, the figure of 21 percent of screening-eligible beneficiaries who see physicians being tested may be too high. This figure did not include patients who may have had indications for TSH testing that were not listed on claims and physicians may have a lower inclination to screen than they do to test patients with indications for diagnostic testing. Using a range of possibilities, 1.3 percent to 7.7 percent available for testing and testing 10 percent to 80 percent of those available, the percentage of Medicare beneficiaries tested could be as low as 0.1 percent or as many as 6.2 percent.

Calculating the net costs of a serum TSH screening program entails comparing the incremental medical costs likely to be incurred from screening a population for thyroid dysfunction versus the diagnosis and treatment of thyroid dysfunction that now occurs in usual care. Under usual care, people receive treatment for thyroid dysfunction if their clinicians diagnose it, but there is no systematic screening program. The net costs of a screening program consist of the following components:

1. Costs of the screening program, including (a) serum TSH tests and (b) evaluation of any positive test results to distinguish people who do not have thyroid dysfunction (false positives) from those who do (true positives);

2. Net costs of treating thyroid dysfunction, calculated as the difference between (a) the cost of treating thyroid dysfunction detected by the screening program and (b) the cost of treating thyroid dysfunction diagnosed under usual care; and

3. Any net savings in treatment costs from preventing mortality and morbidity associated with thyroid dysfunction and secondary disorders in (a) people detected by the screening program compared with (b) people under usual care.

Tables 5-3A through 5-3C list the specific medical services that may be involved in screening and treating thyroid dysfunction. Under the screening program (Part A), all people screened would initially receive a serum TSH test, and those with positive test results would receive an office visit, a repeat serum TSH test, and a serum free T₄ test to confirm the abnormal results and rule out false positives. Those with high serum TSH results indicating subclinical or overt hypothyroidism (Part B) and those with low serum TSH results indicating subclinical or overt hyperthyroidism (Part C) would subsequently receive additional tests, consultations, visits, and therapies to evaluate and then treat the condition. If treatment for the thyroid dysfunction was effective, it might ameliorate the condition, reduce services associated with unrecognized symptoms of the condition, or reduce services associated with secondary disorders and thereby achieve savings in costs.

The dearth of current evidence on the effectiveness of thyroid screening restricts the calculation of the full range of net costs associated with a screening program. Because evidence is lacking on the likely health benefits of screening, there is no reasonable basis for estimating whether a screening program would detect thyroid dysfunction more effectively than usual care and, hence, how the costs of treating thyroid dysfunction under the alternative strategies would compare. On the one hand, if screening only reduced the lead time to identify and treat people with thyroid dysfunction, the incremental costs of treatment might be quite small; most of the same costs would be incurred without screening, only later in time. In this regard, we know that the overall rate of progression of subclinical hypothyroidism to overt hypothyroidism is low, a few percentage points per year, but higher in those people with higher serum TSH concentrations or high serum anti-thyroid antibody concentrations (see Chapter 3). In a few people, however, serum TSH concentrations return to normal with time.

On the other hand, if screening identified people who otherwise would not be diagnosed and treated under usual care, the incremental costs of screening would be closer to the full amount of the costs of treating those people identified by screening. Without evidence on the effectiveness of screening, we have no basis for estimating where in that range incremental treatment costs are likely to fall; nor is there a reasonable basis for estimating the extent to which treatment of cases detected through screening would prevent the use of services, morbidity, or mortality associated with thyroid dysfunction and secondary disorders. Therefore, we lack an adequate basis for estimating whether any net savings in the costs of treating these sequelae would occur.

In the absence of sufficient evidence to estimate these health benefits and their associated medical costs, we have estimated the components of a cost analysis that do not incorporate an assessment of the effectiveness of screening: the costs of the screening program and the costs of treating cases detected by screening. For a cohort of 1 million Medicare beneficiaries 65 years or older who were screened, Tables 5-4A and 5-4B provide estimates of the prevalence of thyroid dysfunction that would be detected and the services that would be used to further evaluate and treat those people found to have thyroid dysfunction. Data are available that allow an estimate of the prevalence of abnormal screening serum TSH values (see the references accompanying Tables 5-4A and 5-4B), but it should be noted that some of these data are not from studies of screening. Nor are they from studies of people age 65 and older. No data are available on how people with subclinical thyroid dysfunction are evaluated or the proportion that is treated, so the estimates are drawn from the expert opinions of the Committee members. We have not attempted to estimate potential savings because of the complete absence of relevant data.

The estimates of how many people with abnormal screening serum TSH values would be further evaluated and treated are based on the following considerations. The base case contains the most reasonable estimate of each variable,

and the lowest and highest cases contain the range of values that would be associated with the lowest and highest estimates of costs, respectively:

• All people with an abnormal screening serum TSH value would have at least an office visit, a repeat serum TSH test, and a serum free T₄ test. This is the ideal response to abnormality detected by screening, and the actual proportion having this further evaluation is likely to be lower.

• There are no recent data (<10 years old) indicating how physicians would evaluate people with overt thyroid disease and no data at all indicating how they would evaluate people with subclinical thyroid disease; nor are there data indicating what proportion of people with either subclinical hypothyroidism or subclinical hyperthyroidism would be treated. The estimates given are based on the best estimates of the Committee.

• In regard to treatment of subclinical hypothyroidism and subclinical hyperthyroidism, it is important to note that most people with either condition have serum TSH concentrations that are close to the limits of normal. This is one reason why the value for the base case is relatively low. The lowest and highest cases are set far apart because of the uncertainty about the proportions likely to be treated. Nearly all people with overt thyroid disease would be treated.

• We assumed that all patients who were treated for either subclinical or overt hypothyroidism would have the specified numbers of follow-up visits and tests. Therefore, the numbers of people listed at the bottom of Table 5-4A, are the combined numbers for the subclinical and overt groups.

• The causes of both subclinical and overt hyperthyroidism were assumed to be Graves’ disease (50 percent), nodular goiter (30 percent), and thyroiditis and other causes (20 percent). (There are no published data concerning the causes of subclinical hyperthyroidism as detected by screening.) We assumed that considerably fewer patients with subclinical hyperthyroidism would be treated (base case, 30 percent versus 90 percent for overt hyperthyroidism) because many of the former have only very slightly high serum TSH concentrations (and some would have thyroiditis and need no treatment). We assumed that 50 percent of people with subclinical hyperthyroidism and 50 percent of those with overt hyperthyroidism who were treated would be given radioactive iodine, and the other 50 percent would receive an anti-thyroid drug.

• For both subclinical and overt hyperthyroidism, we assumed that all people who were treated would receive three office visits and sets of tests in the first year of treatment and that the number of visits and tests would be independent of the type of treatment.

• Some people (estimated as 50 percent because people with both Graves’ disease and nodular goiter are included) treated for hyperthyroidism with radioactive iodine would develop hypothyroidism. (We assumed this would occur during year 1.) Therefore, in year 2 and thereafter, they would be followed according to the schedule for people with hypothyroidism in Table 5-4A. We

recognize that this treatment is more likely to cause hypothyroidism in people with Graves’ disease than in those with nodular goiter and consider the estimate of 50 percent to be very crude. Moreover, a few people treated with radioactive iodine would probably develop hypothyroidism later.

• For years 2 and thereafter, the remaining people with hyperthyroidism who were treated would be followed as indicated at the bottom of Table 5-4B. Some of these people might be treated with radioactive iodine and others, particularly those with Graves’ disease, might have a remission of their disease and need no antithyroid drug treatment and less frequent testing.

• There are no published data that address the question of optimal follow-up for people with either hypothyroidism or hyperthyroidism.

Many more branches or steps could be added to this table. For example, the types of diagnostic studies were limited. As we have noted, we assumed that all people who were treated for hypothyroidism or hyperthyroidism would have the specified follow-up visits and tests, an unlikely outcome in clinical practice. The combining of visits and tests during and after treatment for hyperthyroidism independent of the particular treatment given is certainly an oversimplification. We have made no provision for the side effects of antithyroid drug or radioactive iodine therapy, except for radioactive iodine-induced hypothyroidism.

The unit costs for each visit, test, and treatment are shown in Tables 5-5A and 5-5B. Price information for all services except prescription drugs were obtained from the Medicare program’s published Fee Schedules for 2003 (Centers for Medicare and Medicaid Services, 2003). Where fee schedule amounts differed among localities, the median figure was used. Prescription drug prices were obtained from an Internet prescription drug price search engine (DestinationRx, Inc., 2003) that compares prices from major national retail sources, including shipping costs. The prices selected for methimazole and propylthiouracil represent the mid-point between the highest and lowest prices quoted for 100 pills. The price chosen for levothyroxine was the lowest quoted price for 100 tablets of the leading brand name.

Tables 5-6A through 5-6C show our cost estimates for each 1 million Medicare beneficiaries screened. A large proportion of the cost comes from lifetime monitoring and drug treatment. Because the portion of the Medicare population affected by screening would be younger and healthier than average, we estimated the average life expectancy of beneficiaries who screen positively and are treated to be 17 years, the average life expectancy for individuals ages 66 and 67 (National Center for Health Statistics, 2002). As Table 5-6A shows, our base case cost estimate for the screening test itself is $23.5 million, all of which would be paid by the Medicare program. The lifetime cost estimate of treatment and follow-up for those patients whose initial test results indicated hypothyroidism (Table 5-6B) was $98.8 million per million subjects screened; $46.6 million would be paid by Medicare and $52.2 million would paid by Medicare beneficia

ries or supplementary insurance. Most of the cost not paid by Medicare, $42.7 million, is for prescription drugs. The lifetime cost estimate of treatment and follow-up for those patients whose initial test results indicated hyperthyroidism (Table 5-6C) was $11.1 million per million subjects screened; $8.5 million would be paid by Medicare and $2.6 million would paid by Medicare beneficiaries or supplementary insurance. Again, most of the cost not paid by Medicare, $1.5 million, is for prescription drugs. These estimates are very sensitive to the proportion of subjects tested who have positive screening results: An increase of 1 percent in the prevalence of elevated serum TSH levels (from 6 percent to 7 percent) would raise the base cost estimate for hypothyroidism by $16.5 million per million subjects screened. An increase in the prevalence of low serum TSH levels from 1 percent to 2 percent would increase the base cost estimate for hyperthyroidism by $11.1 million.

Combining our estimates of the number of beneficiaries screened with the estimates of costs per million beneficiaries screened, we can estimate the annual cost to the Medicare program. These results are given in Tables 5-7A through 5-7C. Our base estimates of 250,000 beneficiaries screened would cost Medicare $5.9 million for the screening tests, $11.6 million for follow-up and treatment of suspected hypothyroidism and $2.1 million for follow-up and treatment for suspected hyperthyroidism.

Estimates of the costs of screening require an estimate of the number of subjects who will be screened and the net costs incurred (or saved) as a result of screening.

Historically, the use of preventive services by Medicare beneficiaries has been considerably less than universal among those covered for the service; important factors have limited demand or created other barriers to use. In the case of serum TSH testing, more than 90 percent of Medicare beneficiaries have indications for testing that are already covered by the Medicare program. Aside from beneficiaries with known thyroid disease, fewer than 25 percent of beneficiaries with these indications are tested annually. On this basis, the Committee estimates that a relatively small number of Medicare beneficiaries would take advantage of a serum TSH screening benefit; our best estimate is 250,000 annually.

The Committee found a widespread lack of information necessary to make a meaningful assessment of the true economic costs of screening. It could not estimate costs avoided or other possible benefits resulting from screening or whether any costs incurred would be postponed rather than avoided if screening were not done. The Committee was able to estimate the health care resources likely to be expended as a consequence of screening. Our best estimate for 250,000 beneficiaries screened was $33.3 million annually. The Medicare program would pay $19.6 million of this total; supplementary insurance or the beneficiaries themselves would pay the remainder.

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