Cover Image

PAPERBACK
$63.25



View/Hide Left Panel

Appendix K
Cost Issues in Cost Effectiveness Modeling of Colorectal Cancer Screening Martin L.Brown, Ph.D.

SLIDE 1

SLIDE 1 NOTES: No notes.



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary Appendix K Cost Issues in Cost Effectiveness Modeling of Colorectal Cancer Screening Martin L.Brown, Ph.D. SLIDE 1 SLIDE 1 NOTES: No notes.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 2 SLIDE 2 NOTES: No notes.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 3 SLIDE 3 NOTES: Cost domains refers to the types of costs included in a CEA, such as direct medical costs, time costs and productivity costs. Time costs—the cost to the patient due to lost time of receiving health care-are especially important in large-scale screening programs where a lot of people spend a lot of time in order for a few to benefit from early detection or prevention of colorectal cancer. Productivity costs may be relevant in populations where individuals must take time away from work to get screened. Most models have ignored these two dimensions and focused on the direct medical care costs.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 4 SLIDE NOTES 4: Across the cost continuum-from screening through follow-up, surveillance and treatment of cancer-there is great variability among models in what is assumed. In particular, accounting for the costs of treating colorectal cancer varies across models as to whether it is entered as a one-time package cost or whether it is entered over time and varies with the subsequent life of the patient. The latter approach acknowledges the high initial and terminal costs of treating colorectal costs, while the continuing care components recognizes that costs of treating and monitoring colorectal cancer continue over the course of a person’s life following the initial treatment period.increased by about 2 years in a cohort of 50-year-old individuals. That 2-year difference leads to substantially lower life-expectancies in our model.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 5 SLIDE 5 NOTES: The costs listed above may all be relevant to a cost-effectiveness analysis of a screening program. However, the costs of promotion and recruitment have been largely ignored in most cost-effectiveness analysis. Those costs are basically fixed costs that deliver a certain level of participation in a screening program. These costs have been ignored in models focusing on the US population because in our health system, promotion and recruitment are typically not addressed through explicit organized and government-run screening programs. We have a mixture of publicity and promotion and advertising and public relations, as well as physician-led recruitment. We don’t know much about how much of this activity occurs, much less about how much it costs. In other high-income countries, where governments explicitly organize programs to screen, these fixed costs actually can be and do get estimated in the cost side of the cost-effectiveness analysis. Facilities and equipment costs are implicitly included as amortized costs in procedure costs. (The Medicare fee structure, for example, was constructed with such amortized costs in mind.) But, when the fixed costs are incurred up front, in a short period of time, they may become financial constraints that health care providers or plans must take into account. Such issues are not considered in the models. Time costs are typically not included in models, most likely because we simply do not have good estimates of such costs. NCI is currently conducting work that will provide estimates of time costs associated with treatment of CRC by phase of disease. It would be relatively straight-forward to get time costs for screening and diagnostic phases.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary Quality control costs are typically not considered in the models of CRC screening. But such costs can be real, if not major. For example, a cost-benefit analysis of the Mammography Quality Standards Act estimated that quality control and program evaluation costs for that technology were on the order of $2 or $3 per examination, compared with total costs of $50 to $100 per examination. As colorectal cancer screening evolves in the US, explicit quality control programs will undoubtedly be required. SLIDE 6 SLIDE 6 NOTES: The first two sources of data for estimating procedure or program costs involve direct measurement of the inputs (and their values) that go into performing specific tasks involved in screening and treatment. They are not widely available, but they may merit more work, because the alternative source of costing data—administered prices—are largely based on custom, history, and relative bargaining power of the buyers and sellers of procedures. They may be only loosely related to the true quantity and value of inputs required to produce the procedure or service. This is particularly true if the price of a screening procedure is based on its use as a diagnostic service, which can involve very different resource requirements. Consequently, I believe that relying on historical prices to represent the true resource cost of a mass screening program probably overestimates the true screening cost. Yet, it may be disingenuous to base a cost-

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary effectiveness analysis on an efficient price, drawn perhaps from a time-and-motion study, when in fact the patient or health plan will have to pay the price established through an administered pricing system. In that case, the realized cost may be two or three times higher than those assumed in the cost-effectiveness analysis. SLIDE 7 SLIDE 7 NOTES: Here are some of the obvious sources of variation in estimated costs across the CEA studies we are examining in this workshop. One very important issue is whether the study includes a charge for the additional unrelated future health care costs that would be incurred simply as a result of screened patients living longer. Later slides will refer to this issue in more detail.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 8 SLIDE 8 NOTES: Here is a table showing the wide range of estimates of the unit cost of sigmoidoscopy among recent studies (Whynes et al., 2003). It is no wonder that we get differences in cost-effectiveness ratios when there is such a wide range of costs of the procedure. The screening cost accounts for a large proportion of the entire lifetime cost. A difference in costs by a factor of four or five would obviously affect the conclusions of an analysis.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 9 SLIDE 9 NOTES: No notes.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 10 SLIDE 10 NOTES: Here is an example of unit costs estimated in the context of a clinical trial of one-time sigmoidoscopic screening in England (Whynes et al., 2003). Note that the time cost as estimated in the trial is not a trivial proportion of the entire unit cost of screening.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 11 SLIDE 11 NOTES: Here is an example of issues in costing of FOBT (Frazier et al., 2000). The current reimbursement from Medicare for an FOBT is about $4.50. Many studies assume that Medicare’s allowed amount is the cost for FOBT. However, if one must visit a primary care physician to receive and be instructed in the proper application of the test, the cost would be an additional $40. Even if you assume that the FOBT is only one-half the cost of the visit, the procedure cost increases dramatically. Of course the question is whether that is a reasonable way to do it. We rely on physicians to recruit their patients, but we could also envision an FOBT screening program where recruitment is population-based and does not involve a physician encounter. (Many European FOBT screening programs follow that paradigm.) Appropriate costing of that screening paradigm would start with the $4.50 cost, and then add, say a fixed cost of $500,000 (for recruitment operations) divided over the number of individuals who are screened by such a program.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 12 SLIDE 12 NOTES: Here is an example of how a seemingly small detail of a screening protocol can have major implications for costs (Klabunde et al., 2003). It makes a big difference whether a lesion found on sigmoidoscopy is biopsied on the spot, or whether the patient is referred for colonoscopy. In a 2000 survey of primary care physicians who do flexible sigmoidoscopy (NOT gastroenterologists), we found that less than one-third said they would actually take a biopsy as part of the screening procedure. In practice, then, the majority of primary care practitioners do refer to colonoscopy, with major consequences for costs.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 13 SLIDE 13 NOTES: The question of how unrelated costs are treated is very important, because the cost-savings due to avoided treatment is a very large part of the net cost of a screening program. So, even modest changes in the estimate of cost savings can make huge differences in the final cost-effectiveness ratio. We can ask, however, what would happen to a person who, because of screening, is spared a CRC. That person will eventually die of some other cause, and the cost of treating that condition may be similar to the cost of treating colorectal cancer. In most cases, we hope, it would be later in time, and when costs are discounted to their present value, there would be some net savings even if the absolute costs did not decline. In addition, during the extra years of life that a person lives, he or she would obtain medical care, which would also decrease the net savings from prevention of CRC. There is no consensus, however, about whether the extra costs associated with longer life or competing causes of death should be included in CEA (Gold et al., 1996).

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 14 SLIDE 14 NOTES: What are the implications of including or excluding unrelated health care costs from the treatment cost estimate? The table in this slide shows the results of a study in which we examined that question (Etzioni et al., 2001). We examined the treatment cost of colorectal cancer by stage. All of the costs in the first column are cancer related. However, if one includes the unrelated costs of living longer, the costs available to be averted through screening are reduced. The later the stage at diagnosis, the lower the potential cost savings from prevention become, and at the latest stage prevention actually increases costs. In that case, instead of saving costs of treatment, it actually costs $9,000 more. That is because individuals diagnosed in stage 4 tend to die quickly, and all the usual health care expenses are avoided. I do not know what effect such different cost assumptions would have on the outcomes of CEAs, as it would depend upon the distribution of incidence across the stages of disease and the impact of a screening strategy on each particular stage. But the differences in cost imply that the results could be quite sensitive to the inclusion or exclusion of these costs.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 15 SLIDE 15 NOTES: Surveillance assumptions are a large component of the total lifetime costs of a screening program. If the frequency of surveillance is low, or if it is conditioned on the size of the polyp or other criteria, the overall program costs will be lower than it would be if one were to assume a uniform policy of surveillance with colonoscopy every three years. A related question in this regard is whether the assumptions regarding surveillance should reflect a ‘best practices” or guidelines-based surveillance regimen, or a surveillance regimen that reflects actual practice.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 16 SLIDE 16 NOTES: We addressed the question of the impact of using guidelines-based surveillance versus a strategy that assumes surveillance occurs ever 3 years (van Ballegooijen et al., 2003). That study was for an immunochemical FOBT test in a program that extended over 30 years and discounted at 3 percent per year. Total program costs almost doubled between current guidelines for surveillance and a uniform once-every-three-years surveillance practice.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 17 SLIDE 17 NOTES: No notes.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary SLIDE 18 SLIDE 18 NOTES: There is a paucity of studies that try to establish the most efficient cost of providing screening services. That is, how should such programs be organized and delivered so as to deliver the particular services associated with a screening strategy in the most efficient manner. For example, assuming that flexible sigmoidoscopy screening would be carried out mainly by primary care physicians, the cost implications would be different from those under a sigmoidoscopy screening program carried out by gastroenterologists, or by screening endoscopy mills, a term I use in a positive sense, because of their potential to deliver endoscopic services efficiently. Today, we have almost no information on the relative costs of delivering screening services in those different organizational environments. I am not even sure where such a responsibility for sponsoring such studies would lie, whether at NIH or at AHRQ.

OCR for page 189
Economic Models of Colorectal Cancer Screening in Average-Risk Adults: Workshop Summary REFERENCES Etzioni R, Ramsey SD, Berry K, Brown M. 2001. The impact of including future medical care costs when estimating the costs attributable to a disease: A colorectal cancer case study. Health Economics. 10(3):245–256. Frazier AL, Colditz GA, Fuchs CS, Kuntz KM. 2000. Cost-effectiveness of screening for colorectal cancer in the general population. JAMA. 284(15):1954–1961. Gold MR, Siebel JE, Russell LB, Weinstein MC, Editors. 1996. Cost-Effectiveness in Health and Medicine. New York: Oxford University Press. Klabunde CN, Frame PS, Meadow A, Jones E, Nadel M, Vernon SW. 2003. A national survey of primary care physicians’ colorectal cancer screening recommendations and practices. Prev Med. 36(3):352–362. Mandel JS, Church TR, Ederer F, Bond JH. 1999. Colorectal cancer mortality: Effectiveness of biennial screening for fecal occult blood. J Natl Cancer Inst. 91(5):434–437. van Ballegooijen M, Habbema JDF, Boer R, Zauber AG, Brown ML. 2003. Report to the Agency for Health Care Research and Quality: A Comparison of the Cost-Effectiveness of Fecal Occult Blood Tests with Different Test Characteristics in the Context of Annual Screening in the Medicare Population. Whynes DK, Frew EJ, Edwards R, Atkin WS. 2003. Costs of flexible sigmoidoscopy screening for colorectal cancer in the United Kingdom. Int J Technol Assess Health Care. 19(2):384–395. The effect of fecal occult-blood screening on the incidence of colorectal cancer. N Engl J Med. 343(22):1603–1607. Vijan S, Hwang EW, Hofer TP, Hayward RA. 2001. Which colon cancer screening test? A comparison of costs, effectiveness, and compliance. Am J Med. 111(8):593–601.