Appendix EDescription of the Laudabaum Colorectal Cancer Screening Model

Ladabaum U.

Publication Details

Slide 1. Appendix E Description of the Laudabaum Colorectal Cancer Screening Model.

Slide 1

Appendix E Description of the Laudabaum Colorectal Cancer Screening Model. SLIDE 1 NOTES: This summary describes key elements of the current version of a model used in a cost-effectiveness analysis published by my colleagues and me (Song et al., 2004) (more...)

Slide 2. Model Structure.

Slide 2

Model Structure. SLIDE 2 NOTES: Our model is a cohort model. The main outputs are average years of life lived and accrued costs per person. It can be an converted to an aggregate annual model by combining the estimates for every age group in each year (more...)

Slide 3. Schematic of Natural History Model.

Slide 3

Schematic of Natural History Model. SLIDE 3 NOTES: This is a schematic of the natural history model. At the left, we start with people in the normal state. They can progress to a small polyp (less than 10 mm), which is our nomenclature for a low-risk (more...)

Slide 4. Approach to Modeling Natural History.

Slide 4

Approach to Modeling Natural History. SLIDE NOTES 4: Our model starts with the adenoma-carcinoma sequence. We model adenomatous polyps, which are generally agreed to be the precursor lesions for most colorectal cancers. We started with polyp prevalence (more...)

Slide 5. Model vs. Polyp Prevalence (autopsy).

Slide 5

Model vs. Polyp Prevalence (autopsy). SLIDE 5 NOTES: To estimate the transition probabilities we used various data sources. For transitions from normal mucosa to small polyp, and from small polyps to large polyps we used age-specific data from autopsy (more...)

Slide 6. Model vs. SEER.

Slide 6

Model vs. SEER. SLIDE 6 NOTES: The graphs in this slide show how the model, as calibrated by SEER data (Ries et al., 1997), compares to the age- and stage-specific incidence rates.

Slide 7. Assumptions About Compliance.

Slide 7

Assumptions About Compliance. SLIDE 7 NOTES: Incremental effectiveness of screening compared with no screening is affected by compliance, but incremental cost-effectiveness is not. Note that when we assume less than 100 percent compliance, the incremental (more...)

Slide 8. Assumptions About Cost.

Slide 8

Assumptions About Cost. SLIDE 8 NOTES: Until now, the health care costs associated with dying of other causes has been set at 0. The model could accommodate other assumptions, however. In addition, those costs could be age-dependent, if reasonable data (more...)

Slide 9. Model Validation: Natural History.

Slide 9

Model Validation: Natural History. SLIDE 9 NOTES: To validate the model, we examined the age-specific outcomes of the model and compared them with national data for the year 2000. We were gratified that the estimated number of cancer cases in our model (more...)

Slide 10. Assumptions About Cost.

Slide 10

Assumptions About Cost. SLIDE 10 NOTES: In the Minnesota study, screening occurred in only some of the years over the course of the trial, and imperfect adherence with screening was attained (Mandel et al., 2000; Mandel et al., 1993). Overall, in that (more...)

Slide 11. Model Strengths and Weaknesses.

Slide 11

Model Strengths and Weaknesses. SLIDE 11 NOTES: It is possible for the model to evaluate the costs and effectiveness of screening in populations with different levels of risk for polyps and cancer. We are currently working on making predictions at the (more...)


  • Arminski TC, McLean MD. Incidence and distribution of adenomatous polyps of the colon and rectum based on 1,000 autopsy examinations. Dis Colon Rectum. 1964;7:249–261. [PubMed: 14176135]

  • Clark JC, Collan Y, Eide TJ, Esteve J, Ewen S, Gibbs NM, et al. Prevalence of polyps in an autopsy series from areas with varying incidence of large-bowel cancer. Int J Cancer. 1985;36(2):179–186. [PubMed: 4018911]

  • Jemal A, Murray T, Samuels A, Ghafoor A, Ward E, Thun MJ. Cancer statistics, 2003. CA Cancer J Clin. 2003;53(1):5–26. [PubMed: 12568441]

  • Ladabaum U, Chopra CL, Huang G, Scheiman JM, Chernew ME, Fendrick AM. Aspirin as an adjunct to screening for prevention of sporadic colorectal cancer: A cost-effectiveness analysis. Ann Intern Med. 2001;135(9):769–781. [PubMed: 11694102]

  • Ladabaum U, Scheiman JM, Fendrick AM. Potential effect of cyclooxygenase-2 - Specific inhibitors on the prevention of colorectal cancer: A cost-effectiveness analysis. Am J Med. 2003;114(7):546–554. [PubMed: 12753878]

  • Mandel JS, Bond JH, Church TR, Snover DC, Bradley GM, Schuman LM, Ederer F. Reducing mortality from colorectal cancer by screening for fecal occult blood. N Engl J Med. 1993;328(19):1365–1371. [PubMed: 8474513]

  • Mandel JS, Church TR, Bond JH, Ederer F, Geisser MS, Mongin SJ, Snover DC, Schuman LM. The effect of fecal occult-blood screening on the incidence of colorectal cancer. N Engl J Med. 2000;343(22):1603–1607. [PubMed: 11096167]

  • Rickert RR, Auerbach O, Garfinkel L, Hammond EC, Frasca JM. Adenomatous lesions of the large bowel: an autopsy survey. Cancer. 1979;43(5):1847–1857. [PubMed: 445371]

  • Ries LAG, Kosary CL, Hankey BF, Miller BA, Harras A, Edwards BK. SEER Cancer Statistics Review, 1973-1994. Bethesda, MD: National Cancer Institute; 1997.

  • Sandler RS, Everhart JE, Donowitz M, Adams E, Cronin K, Goodman C, Gemmen E, Shah S, Avdic A, Rubin R. The burden of selected digestive diseases in the United States. Gastroenterol. 2002;122(5):1500–1511. [PubMed: 11984534]

  • Selby JV, Friedman GD, Quesenberry CP Jr, Weiss NS. A case-control study of screening sigmoidoscopy and mortality from colorectal cancer. N Engl J Med. 1992;326(10):653–657. [PubMed: 1736103]

  • Song K, Fendrick AM, Ladabaum U. Fecal DNA Testing Compared with Conventional Colorectal Cancer Screening Methods: A Decision Analysis. Gastroenterol. 2004;126(5):1270–1279. [PubMed: 15131787]

  • Vatn MH, Stalsberg H. The prevalence of polyps of the large intestine in Oslo: An autopsy study. Cancer. 1982;49(4):819–825. [PubMed: 7055790]

  • Williams AR, Balasooriya BA, Day DW. Polyps and cancer of the large bowel: a necropsy study in Liverpool. Gut. 1982;23(10):835–842. [PMC free article: PMC1419830] [PubMed: 7117903]

  • Winawer SJ, Zauber AG, May Nah Ho, O'Brien MJ, Gottlieb LS, Sternberg SS, Waye JD, Schapiro M, Bond JH, Panish JF, Ackroyd F, Shike M, Kurtz RC, Hornsby-Lewis L, Gerdes H, Stewart ET, Lightdale CJ, Edelman M, Fleisher M. Prevention of colorectal cancer by colonoscopic polypectomy. N Engl J Med. 1993;329(27):1977–1981. [PubMed: 8247072]