Parameter | Base case | SE or range | Distribution | Source/references |
---|---|---|---|---|
Annual transition probabilities | ||||
Normal to low-risk | 0.1976 | 0.0044 | Beta | Based on the National Cancer Institute pooling project [25] (S 3.1) |
Low-risk state to high-risk | 0.0890 | 0.0028 | Beta | Meta-analysis of 4 data sets of population with high-risk adenomas at baseline (S 3.2) |
High-risk to CRC1pre | ASR | NA | NA | Birth cohort analyses from German screening colonoscopy registry [26, 27] (S 3.3) |
CRC1pre to CRC2pre | 0.2800 | 0.0357 | Beta | Estimated by calibration to the National Cancer Institute data statistics [28], 1973–1999 |
CRC2pre to CRC3pre | 0.2800 | 0.0357 | Beta | |
CRC3pre to CRC pre | 0.6300 | 0.1405 | Beta | |
CRC1pre to CRC1cli (by symptoms) | 0.0700 | 0.0300 | Beta | Reported in an economic evaluation by Frazier AL et al. [29] |
CRC2pre to CRC2cli (by symptoms) | 0.2500 | 0.0577 | Beta | |
CRC3 pre to CRC3cli (by symptoms) | 0.5500 | 0.0577 | Beta | |
CRC4pre to CRC4cli (by symptoms) | 0.8500 | 0.0763 | Beta | |
CRC1cli to dead | 0.0575 | 0.0087 | Beta | Based on meta-analyses of five studies reported survival data of CRC at different stages in Malaysia (S 3.8) |
CRC2cli to dead | 0.0684 | 0.0099 | Beta | |
CRC3cli to dead | 0.0973 | 0.0132 | Beta | |
CRC4cli to dead | 0.1589 | 0.0666 | Beta | |
Effectiveness: every 3-year colonoscopy | ||||
Low-risk state to normal | 0.5800 | 0.0178 | Beta | Based on meta-analyses of per-patient miss rate (S 3.4.1–2) |
High-risk state to normal or low-risk state | 0.9200 | 0.0204 | Beta | |
CRC1pre to CRC1cli | 0.9470 | 0.013 | Beta | Available from a meta-analysis by Pickhardt PJ et al. [30] |
CRC2pre to CRC2cli | 0.9470 | 0.013 | Beta | |
CRC3pre to CRC3cli | 0.9800 | 0.9500–0.9900 | Uniform | Available from an economic evaluation from the National Institute for Health Research (NIHR) (S 3.5) |
CRC4pre to CRC4cli | 0.9800 | 0.9600–1.0000 | Uniform | |
Relative risk (RR) of benefits associated with ASAVLD | Â | Â | Â | |
Normal to low-risk | 0.86 | 0.0740 | Normal | Meta-analyses of two aspirin chemoprevention RCTs [39, 40] (S 3.6) |
Low-risk to high-risk | 0.59 | 0.1352 | Normal | |
RR of CV mortality | 0.92 | 0.0536 | Normal | Reported in a recent network meta-analysis by Veettil et al. [37] |
Harms associated with interventions | ||||
Intolerability due to initial side effects of ASAVLD | 0.052 | 0.025–0.200 | Uniform | Derived from an aspirin chemoprevention trial [39] |
Major bleeding (any) due to ASAVLD per year | 0.0022 | 0.0005 | Beta | Available from a meta-analysis of nine primary CV disease prevention trials [34] (S 3.7.1) |
Major GI bleeding due to ASAVLD | 0.0011 | 0.0003 | Beta | Available from the systematic review undertaken for the USPSTF [35, 36] and Veettil et al. [37] (S 3.7.2) |
Ulcer due to ASAVLD | 0.0018 | 0.0002 | Beta | |
Dyspepsia due to ASAVLD | 0.1880 | 0.0800 | Beta | |
Perforation due to colonoscopy (with or without polypectomy) | 0.0004 | 0.00008 | Beta | Based on a systematic review undertaken for the USPSTF by Lin JS et al. [31] |
Major bleeding due to colonoscopy | 0.0008 | 0.0002 | Beta | |
Mortality due to perforation | 0.0582 | 0.0100 | Beta | Available from a large population-based cohort study by Gatto NM et al. [38] |
Mortality due to major bleeding events | 0.0600 | 0.0100–0.1600 | Uniform | Reported in a recent network meta-analysis by Veettil et al. [37] |
Utility values | ||||
Non-CRC states | 0.8300 | 0.0500 | Beta | Based on a population based cross-sectional study using EQ-5D instrument [40] (S 3.9) |
CRC I | 0.7400 | 0.0260 | Beta | Ness et al. [39] |
CRC II | 0.7400 | 0.0260 | Beta | |
CRC III | 0.6700 | 0.0289 | Beta | |
CRC IV | 0.2500 | 0.0551 | Beta | |
Colonoscopy (disutility) | 0.0025 | NA | NA | Reported in an economic evaluation by Saini SD et al. [57] (S 3.9) |
Major GI bleeding/peptic ulcer due to ASAVLD (1Â month) | 0.46 | NA | NA | Based on the analysis undertaken for the NICE osteoarthritis guidelines (S 3.9) |
Dyspepsia (1Â month) | 0.73 | NA | NA | |
Base case assumptions | ||||
Annual discount rate for costs and outcomes | 0.03 | NA | NA | Pharmacoeconomic guideline, Malaysia (https://www.pharmacy.gov.my/v2/en/documents/pharmacoeconomic-guideline-malaysia.html) |
Compliance to surveillance colonoscopy | 60% | 30–100% | NA | Taylor et al. [58] |