Write a design brief
Turn a messy ER problem into a clear design brief that lists what the design must do (criteria) and the limits it must stay inside (constraints).
- Stating a problem without naming the solution: A design brief describes the need to be met, not one chosen answer; mixing them in locks you into a solution too early.
- Writing a goal you can measure: Criteria and constraints only work if they can be checked, so you first need to turn a vague wish into a measurable statement.
Prerequisites are inferred: pending teacher review.
Re-learn the skill with worked practice and clear examples.
A design brief lists criteria (what the design must do, each one checkable) and constraints (the limits it must stay inside, like cost, space, or time).
A brief says: 'The redesigned ER must triage every walk-in patient within 10 minutes, and the whole project must cost no more than $50,000.' Which part is a CONSTRAINT?
Reviewed- A.Triage every walk-in within 10 minutes
- B.The project must cost no more than $50,000
- C.Both statements are criteria
- D.Neither statement can be checked
Show the worked solution ▾
Answer: B. The project must cost no more than $50,000
- Step 1: Ask what each statement is: The 10-minute triage is a goal the design must achieve: that is a criterion. The cost limit is a boundary the team cannot cross.
- Step 2: Match to the definition: A constraint is a limit the design must stay inside. The $50,000 cap is a limit, so it is the constraint.
Why it's right: The $50,000 cap is a fixed limit the design must stay within, which is the definition of a constraint; the 10-minute triage is a goal, so it is a criterion.
- A: Triaging within 10 minutes is a goal the design must meet, which makes it a criterion, not a constraint.
- C: The 10-minute triage is a criterion and the cost cap is a constraint, so they are not both criteria.
- D: Both statements can be checked: one with a stopwatch, one with a budget total.
Aligned to Design process: criteria vs. constraints · reading level ~grade 9
- A medical-device team posts its criteria and constraints on the wall so that every prototype is checked against the same agreed list, not against personal opinion.
Fill these in as you work through the lesson.
- Design brief (the short written plan for a design):
- Criterion (a thing the design MUST do, and you can check it):
- Constraint (a limit the design must stay inside, like cost or space):
- Human factors (how real people use a design under stress):
A statement that says what the design must achieve is a . A statement that says what limit it must stay inside is a .
- Rewrite the wish 'make the ER nicer' as one criterion you could actually measure.
- List two constraints a real hospital ER design team cannot ignore.
- Explain why a design brief should describe the problem and not jump to one finished answer.
An ER team is told: 'Patients with chest pain wait too long and get lost in the crowd.' Write one criterion and one constraint for the redesign, and explain how you would check each one.