CADTH (CDA-AMC) Guidelines for the Economic Evaluation of Health Technologies: Canada

What it is

— The Guidelines for the Economic Evaluation of Health Technologies: Canada (4th Edition, 2017) is the Canadian health technology assessment (HTA) reference case: a normative methods manual that prescribes the recommended, standardized methods a submitter should follow when conducting an economic evaluation for review by Canada's Drug Agency (CDA-AMC, the agency formerly known as CADTH). It is the Canadian counterpart to the NICE reference case in England and ICER's value framework in the US. The reference case exists to make submissions comparable across technologies and decision problems — it fixes the analytic conventions (perspective, comparators, time horizon, discount rate, outcome metric, handling of uncertainty) so that reviewers can interpret an incremental cost-effectiveness ratio without first having to relitigate every methodological choice. It is maintained by CDA-AMC and was developed through a public, multi-stakeholder consultation process. It is a methods guideline (how to build and parameterize the model), not a reporting checklist and not a critical-appraisal/risk-of-bias instrument.

When to use

— Use this reference case whenever you are preparing or appraising a cost-effectiveness, cost-utility, cost-minimization, or budget-impact analysis intended for a Canadian HTA or pan-Canadian reimbursement decision (CDA-AMC Reimbursement Review / pCPA-bound submissions). It governs the base-case structure: a public health-care-payer perspective, a time horizon long enough to capture all relevant differences in costs and outcomes, QALYs as the primary outcome for cost-utility, prescribed discounting of costs and effects, and explicit characterization of uncertainty. Decision rule for which guideline applies: use this document for the Canadian economic base case; use nice-reference-case for England/NICE submissions (different perspective and discount conventions); use cheers-2022 to report the completed economic evaluation (CHEERS is the reporting checklist, not the methods reference case); and use the CDA-AMC RWE reporting guidance (Tadrous 2024, cited below) when the inputs to your model are drawn from real-world data and must be reported to a Canadian regulator/HTA standard.

What it requires

— The reference case enforces a defined set of methodological domains: (1) a clearly framed decision problem and target population; (2) the choice of evaluation type (cost-utility/CEA preferred, with cost-minimization or budget impact where appropriate); (3) all relevant comparators reflecting current Canadian practice, not just the convenient one; (4) the public health-care-payer perspective for the base case (with broader societal perspectives as scenario analyses); (5) an appropriate time horizon and prescribed discounting of both costs and effects; (6) transparent, validated decision-analytic modelling; (7) effectiveness and safety inputs derived from the best available evidence with explicit handling of indirect/network comparisons and extrapolation; (8) Canadian-context measurement and valuation of health (QALYs via a recognized utility instrument) and of resource use and unit costs; and (9) rigorous characterization of uncertainty — deterministic and probabilistic sensitivity analysis (PSA), structural sensitivity, and scenario analyses — plus consideration of equity. For real-world-data inputs feeding the model (single-arm-trial external comparators from claims/EHR/registry, real-world costs, real-world utilization), the same fitness-for-use and bias discipline expected of any RWE applies: data fitness assessment, validated phenotypes, transparent time-zero and estimand definitions, confounding control, and quantitative bias/sensitivity analysis around the effectiveness and cost parameters.

When NOT to use — limitations and common misapplications

— (1) It is not a reporting checklist. Completing a base case that conforms to the reference case does not satisfy a journal or HTA reporting requirement — report the study with CHEERS 2022 (`cheers-2022`). (2) It is not a critical-appraisal or risk-of-bias tool. It tells you how to build a defensible economic model, not how to grade someone else's observational evidence — use ROBINS-I / GRACE / AMSTAR-style instruments for that. (3) It is jurisdiction-specific. Applying the Canadian perspective, discount rate, and costing conventions to a NICE, IQWiG, or US/ICER submission is a category error; each jurisdiction has its own reference case. (4) Conforming to the reference case does not make biased inputs valid. A pristine model architecture fed by an unadjusted, immortal- time-biased, or poorly phenotyped real-world effectiveness estimate produces a precisely computed wrong answer — the reference case constrains the model, not the credibility of the RWE feeding it. (5) Reference-case-as-theater: presenting only the base case while burying unfavorable structural and parameter uncertainty in an appendix defeats the purpose; PSA and scenario analyses are mandatory, not decorative. (6) Do not confuse this economic-methods reference case with CDA-AMC's separate Guidance for Reporting Real-World Evidence (a reporting standard for RWE submissions) — they are complementary, not interchangeable.

How it maps to this catalog

— The economic-modelling machinery is implemented by `health-economic-modeling-methods-rwe` (model structure and parameterization), `discounting-costs-effects-rwe` (the prescribed discounting of costs and effects), and `probabilistic-sensitivity-analysis-hea-rwe` (the mandatory PSA characterizing parameter uncertainty). The Canadian costing requirements are operationalized by `healthcare-costs-pppm-pppy-pmpm` (real-world cost aggregation), `all-cause-vs-attributable-costs-rwe` (whether to count all-cause or disease-attributable costs), and `cost-outlier-handling-rwe` (treatment of catastrophic/outlier costs in skewed real-world cost distributions). When real-world data supply the effectiveness or external-comparator inputs, fitness and bias are governed by `fit-for-purpose-data-assessment-rwe` (data fitness-for-use), `quantitative-bias-analysis-toolkit-rwe` and `negative-control-outcomes-rwe` (quantitative bias / residual-confounding probes around the effectiveness parameter), with comparative-effectiveness inputs typically built via `active-comparator-new-user` and `target-trial-emulation`. The Canadian-data note: claims/administrative inputs for a Canadian model differ structurally from US Medicare/commercial claims (single-payer provincial coverage, different fee schedules, different drug-plan capture); contrast with `medicare-ffs-ma-commercial-claims-differences-rwe` before importing US-derived utilization or cost estimates into a Canadian reference-case base case. The closest sibling guideline in this catalog is `nice-reference-case` (the England/NICE analogue), with `cheers-2022` as the reporting layer.