Table 1 Parameters of the model and their distributions
Parameter description | Name | Deterministic value | Evidences & Explanation | PSA Distribution* |
|---|---|---|---|---|
Mean Age (at time entering the model) | age | 58 | Patient dataset from Swedish Cancer Registry data [20] | Normal (SD: 11.8) |
General Swedish population Mortality rate | mor_gp | Varies on age | WHO (2021) [36] | NA |
Annual transition probability of | ||||
patient remaining at cancer free | tpA2A | Varies | = 1-tpA2B-tpA2D-tpA2F | NA |
patient having loco-regional recurrence from cancer free | tpA2B | Varies | See Table 2 | Beta (54.84, 944.16) |
patient developing metastasis from cancer free | tpA2D | 0.008 | CI: 0.143 in 20-year followed up [17] | Beta (7.70, 991.30) |
patient remaining at local/regional recurrence | tpB2B | 0.770 | = 1-tpB2C-tpB2F | NA |
patient getting remission after suffering local/regional recurrence | tpB2C | 0.165 | CI: 0.763 in 8-year followed up [31] | Beta (164.52, 834.48) |
patient dying from having local/regional recurrence | tpB2F | 0.065 | CI: 0.49 in 10-year followed up [33] | Beta (65.05, 933.95) |
patient remaining remission after suffering local/regional recurrence | tpC2C | Varies | = 1-tpC2D-tpC2F | NA |
patient developing metastasis after remission from local/regional recurrence | tpC2D | 0.230 | CI: 0.73 in 5-year followed up [34] | Beta (230.16, 768.84) |
patient remaining at metastasis | tpD2D | 0.447 | = 1-tpD2E-tpD2F | |
patient getting remission after suffering metastasis | tpD2E | 0.375 | CI: 0.609 in 2-year followed up [35] | Beta (374.33, 624.67) |
patient dying from having metastasis | tpD2F | 0.178 | CI:0.86 in 10-year followed up [32] | Beta (178.31, 820.69) |
patient remaining remission after suffering metastasis | tpE2E | Varies | = 1-tpE2F | NA |
dying without breast cancer | tpA2F tpC2F tpE2F | Varies | = mor_gp | NA |
remaining death | tpF2F | 1.000 | NA | |
Costs from healthcare perspective (in SEK) | ||||
baseline cost—mastectomy | cam | 87,670 | Patient dataset from Swedish National Cancer Registry data [20] & Socialstyrelsen (2020) [41] | Gamma (656.50, 133.54) |
baseline cost—lumpectomy without irradiation | cal_wo | 27,655 | Gamma (4,253.80, 6.50) | |
baseline cost—lumpectomy with irradiation | cal_w | 50,352 | Gamma (6,217.04, 8.10) | |
at State B, mastectomy | cbm | 17,680 | Gamma (26.70, 662.20) | |
at State B, lumpectomy (either with or without irradiation) | cbl | 87,670 | Gamma (42,749.59, 2.05) | |
at State D, all alternatives | cdm cdl_wo cdl | 499,343 | Lidgren et al. (2008) [40] | Gamma (1,386,844.91, 0.36) |
Other costs from societal perspective | ||||
informal care cost | infocare | 10,003 | Lidgren et al. (2008) [40] | NA |
productivity gained (moving from mastectomy to lumpectomy in first 10-year followed-up) | prod | 4,104 | Norum et al. (1997) [12] | NA |
Utility weights | ||||
State A, mastectomy | uam | 0.84 | Norum et al. (1997) [12] | Beta (839.16, 159.84) |
State A, lumpectomy (either with or without irradiation) | ual | 0.87 | Norum et al. (1997) [12] | Beta (869.13, 129.87) |
State B | ub | 0.78 | Lidgren et al. (2007) [39] | Beta (778.22, 220.78) |
State C | uc | 0.81 | Assumptions: Average of State A and B | Beta (808.69, 190.31) |
State D | ud | 0.69 | Lidgren et al. (2007) [39] | Beta (684.32, 314.69) |
State E | ue | 0.76 | Assumptions: Average of State A and D | Beta (761.74, 237.26) |
Annual discounting rate | ||||
costs (%) | cDR | 3% | Edling and Stenberg (2003) [44] | NA |
benefits (%) | oDR | 3% | Edling and Stenberg (2003) [44] | NA |