| Testing strategy (age range for testing; colonoscopic surveillance interval) | Discounted costs* | Discounted life‐years saved (LYS)* | Cost‐effectiveness ratio: testing v no testing† | Incremental cost‐effectiveness ratio (ICER)‡ |
|---|---|---|---|---|
| Stage 1 analysis | ||||
| 1. No testing | $12 640 | 14.0917 | — | — |
| 7. MSI + MLH1 methylation (no age limit; 1 year) | $19 145 | 14.3061 | $30 338/LYS | Dominated |
| 6. MSI + BRAF V600E (no age limit; 1 year) | $19 130 | 14.3079 | $30 020/LYS | Dominated |
| 5. MSI (no age limit; 1 year) | $19 646 | 14.3113 | $31 904/LYS | Dominated |
| 4. IHC + MLH1 methylation (no age limit; 1 year) | $19 075 | 14.3121 | $29 196/LYS | Dominated |
| 3. IHC + BRAF V600E (no age limit; 1 year) | $19 068 | 14.3140 | $28 915/LYS | $28 915/LYS |
| 2. IHC (no age limit; 1 year) | $19 249 | 14.3148 | $29 625/LYS | $227 000/LYS |
| 8. Universal gene panel testing (no age limit; 1 year) | $26 485 | 14.3178 | $61 235/LYS | $2 411 933/LYS |
| Stage 2 analysis | ||||
| 1. No testing | $12 640 | 14.0917 | — | — |
| 3.3. IHC + BRAF V600E (< 50 years; 2 years) | $13 244 | 14.1441 | $11 525/LYS | $11 525/LYS |
| 3.2. IHC + BRAF V600E (< 50 years; 1 year) | $14 056 | 14.1451 | $26 507/LYS | Dominated |
| 8.3. Universal gene panel testing (< 50 years; 2 years) | $13 746 | 14.1453 | $20 632/LYS | Dominated |
| 8.2. Universal gene panel testing (< 50 years; 1 year) | $14 566 | 14.1461 | $35 397/LYS | Dominated |
| 3.5. IHC + BRAF V600E (< 60 years; 2 years) | $14 155 | 14.2219 | $11 636/LYS | $11 711/LYS |
| 8.5. Universal gene panel testing (< 60 years; 2 years) | $15 989 | 14.2246 | $25 199/LYS | Dominated |
| 3.4. IHC + BRAF V600E (< 60 years; 1 year) | $16 261 | 14.2263 | $26 898/LYS | Dominated |
| 8.4. Universal gene panel testing (< 60 years; 1 year) | $18 131 | 14.2290 | $39 992/LYS | Dominated |
| 3.7. IHC + BRAF V600E (< 70 years; 2 years) | $14 832 | 14.2778 | $11 777/LYS | $12 106/LYS |
| 8.7. Universal gene panel testing (< 70 years; 2 years) | $18 404 | 14.2815 | $30 369/LYS | Dominated |
| 3.6. IHC + BRAF V600E (< 70 years; 1 year) | $17 803 | 14.2845 | $26 776/LYS | Dominated |
| 8.6. Universal gene panel testing (< 70 years; 1 year) | $21 424 | 14.2883 | $44 681/LYS | Dominated |
| 3.1. IHC + BRAF V600E (no age limit; 2 years) | $15 735 | 14.3059 | $14 450/LYS | $32 153/LYS |
| 8.1. Universal gene panel testing (no age limit; 2 years) | $23 101 | 14.3101 | $47 899/LYS | Dominated |
| 3. IHC + BRAF V600E (no age limit; 1 year) | $19 068 | 14.3140 | $28 915/LYS | $411 432/LYS |
| 8. Universal gene panel testing (no age limit; 1 year) | $26 485 | 14.3178 | $61 235/LYS | $1 951 947/LYS |
IHC = immunohistochemistry; MSI = microsatellite instability.
*
Costs and life‐years are each discounted by 5%.
†
Difference in costs divided by difference in LYS for strategy v no testing.
‡
Relative to the next most cost‐effective strategy. “Dominated” indicates that a strategy has either higher costs or a higher cost per LYS than a more effective strategy.