Effects of screening for colorectal cancer: Development, documentation and validation of a multistate Markov model. Issue 8 (5th January 2021)

• Record Type: Journal Article
• Authors: Heisser, Thomas; Hoffmeister, Michael; Brenner, Hermann
• Is Part Of: International journal of cancer. Volume 148:Issue 8(2021)
• Page Start: 1973
• Page End: 1981
• Publication Date: 2021-01-05
• Subjects: colorectal cancer -- modeling -- screening -- validation; Cancer -- Periodicals; Cancer -- Prevention -- Periodicals; 616.994
• DOI: 10.1002/ijc.33437
• Languages: English
• ISSNs: 0020-7136

Abstract

Abstract: Simulation models are a powerful tool to overcome gaps of evidence needed to inform medical decision‐making. Here, we present development and application of COSIMO, a Markov‐based Colorectal Cancer (CRC) Multi‐state Simulation Model to simulate effects of CRC screening, along with a thorough assessment of the model's ability to reproduce real‐life outcomes. Firstly, we provide a comprehensive documentation of COSIMO's development, structure and assumptions. Secondly, to assess the model's external validity, we compared model‐derived cumulative incidence and prevalences of colorectal neoplasms to (a) results from KolosSal, a study in German screening colonoscopy participants, (b) registry‐based estimates of CRC incidence in Germany, and (c) outcome patterns of randomized sigmoidoscopy screening studies. We found that (a) more than 90% of observed prevalences in the KolosSal study were within the 95% confidence intervals of the model‐predicted neoplasm prevalences; (b) the 15‐year cumulative CRC incidences estimated by simulations for the German population deviated by 0.0% to 0.2% units in men and 0.0% to 0.3% units in women when compared to corresponding registry‐derived estimates; and (c) the time course of cumulative CRC incidence and mortality in the modeled intervention group and control group closely resembles the time course reported from sigmoidoscopy screening trials. Overall, COSIMO adequately predicted colorectal neoplasm prevalences and incidences in a German population for up to 25 years, with estimated patterns of the effect of screening colonoscopy resembling those seen in registry data and real‐world studies. This suggests that the model may represent a valid tool to assess the comparative effectiveness of CRC screening strategies. Abstract : What's new? Optimal long‐term strategies for colorectal cancer (CRC) screening, in which health outcomes are balanced with resource use and test burden, remain largely undefined. In this study, to fill‐in evidence gaps and better inform long‐term CRC screening, the authors document the development a model simulating the effects of CRC screening and assessed the model's validity in a large screening colonoscopy study from Germany. The model predicted natural history of CRC for up to 25 years and successfully reproduced screening effects observed in real‐world data. The simulation model is a promising transparent, valid tool, with potential to facilitate medical decision‐making on CRC screening strategies.