CBA Method
How to complete a CBA model
Use Choosing By Advantages to compare alternatives by factual attributes, identify beneficial differences, assign importance to advantages, keep cost separate, and produce a transparent recommendation.
Decision setup
Start with a clear decision question
The setup explains why the decision exists, who owns it, who must validate it, and what requirements cannot be violated.
Required fields
- Decision question
- Owner
- Stakeholders
- Constraints
- Must-have requirements
Quality check
- A reviewer should understand the decision without reading the whole model.
- Avoid generic questions such as Which option is best.
Alternatives
Compare feasible options only
An alternative is an option that could plausibly be selected. Rejected or impossible options can be retained for traceability but should not distort comparison.
Alternative fields
- Name
- Description
- Source
- Feasibility status
- Notes
Review rule
- If an option is infeasible, mark it clearly before building advantages.
Factors and criteria
Define what matters before collecting facts
A factor is a dimension where alternatives may differ. A criterion says what is preferred for that factor.
Criterion examples
- Higher reliability is preferred.
- Lower implementation risk is preferred.
- Closer fit to user workflow is preferred.
CBA discipline
- Do not assign weights to factors as a substitute for advantages.
Attributes and evidence
Record facts before writing advantages
Attributes are factual characteristics of each alternative for each factor. They may be numeric, descriptive, or qualitative, but they should be traceable.
Attribute records should include
- Text value
- Number and unit when useful
- Confidence
- Source type
- Evidence or assumption note
Review rule
- AI-drafted attributes are draft claims until validated by the user.
Advantages and importance
Score beneficial differences, not factor labels
An advantage is a beneficial difference of one alternative compared with another. Importance belongs to the advantage.
Advantage records should include
- Alternative
- Factor
- Compared-against alternative
- Advantage statement
- Magnitude
- Rationale
- Evidence
- Validation status
Scoring discipline
- Use a paramount advantage to calibrate the scale when useful.
- Avoid double-counting the same difference under multiple factors.
Cost and report
Keep resources separate and explain the judgment
Cost, effort, schedule, and resources are compared separately from importance of advantages. The report should show both views and the final rationale.
Report should show
- Ranking by importance
- Cost comparison
- Cost per importance point
- Sensitivity scenarios
- Assumptions
- AI review
- Recommendation