Fecal DNA testing compared with conventional colorectal cancer screening methods: a decision analysis  Kenneth Song, A.Mark Fendrick, Uri Ladabaum  Gastroenterology  Volume 126, Issue 5, Pages 1270-1279 (May 2004) DOI: 10.1053/j.gastro.2004.02.016

Figure 1 Markov states in the Natural History model. After each year, persons could remain in their current disease state (e.g., normal) or progress to another state as shown by the arrows (e.g., normal could progress to small polyp, localized cancer, or dead). CRC-L, localized colorectal cancer; CRC-R, regional colorectal cancer; CRC-D, distant colorectal cancer; Sx, Rx, symptoms and then treatment; s/p, status-post. Gastroenterology 2004 126, 1270-1279DOI: (10.1053/j.gastro.2004.02.016)

Figure 2 Average discounted life expectancy and cost of F-DNA at various screening intervals. Each point represents a different screening interval (e.g., 5y = 5 years). F-DNA at progressively shorter screening intervals yielded increasing average life expectancies but at exponentially increasing incremental costs per life-year gained (represented by the slope of the line between 2 points). Gastroenterology 2004 126, 1270-1279DOI: (10.1053/j.gastro.2004.02.016)

Figure 3 Incremental life-years and cost of COLO compared with F-DNA in 3000 Monte Carlo simulation iterations. Points in the right lower quadrant represent iterations (94%) in which COLO gained more life-years and cost less than (i.e., dominated) F-DNA. Points in the left upper quadrant represent iterations (0.2%) in which F-DNA dominated COLO. Points in the right upper quadrant represent iterations in which COLO was more effective and more costly than F-DNA, with points below the diagonal (2%) representing incremental costs per life-year gained of less than $50,000 and points above the diagonal (0.6%) representing incremental costs per life-year gained of more than $50,000. Points in the left lower quadrant represent iterations in which F-DNA was more effective and more costly than COLO, with points above the diagonal (0.1%) representing incremental costs per life-year gained of less than $50,000 and points below the diagonal (3%) representing incremental costs per life-year gained of more than $50,000. Gastroenterology 2004 126, 1270-1279DOI: (10.1053/j.gastro.2004.02.016)