Lesson 20 · Unit 3

Problem Statements &
Design Specifications

Synthesize research into a precise design direction, then define essential and desirable success criteria.

80 minutesB2.1.8–B2.1.9IA Criterion B

Guiding question: How does research become a clear definition of the project?01

Today’s destination

By the end of class, you should be able to…

Write a problem statement

Explain the current situation, current problem and research basis for the redesign.

Construct specifications

Translate primary and secondary research into essential and desirable success criteria.

Use design categories

Consider attributes, components, constraints, environment, function, user needs, safety, aesthetics and manufacture where relevant.

Prepare Criterion B

Align task-analysis opportunities and existing-product/UI/UX evidence to project definition.

Success check: explain the concept accurately, then use it to make a justified design decision.

Know it → use it → explain the evidence.02

B2.1.8 + Criterion B

A problem statement sets the direction—not the solution.

The guide says the first step in solving a problem is to define it clearly.

Current situation

What is happening now?

Describe intended user, product, task and context.

Current problem

What needs to improve?

Identify the key user difficulties / opportunities supported by task analysis.

Research summary

Why is this problem appropriate?

Synthesize qualitative + quantitative findings that justify the redesign.

A concise problem statement should make the design intention clear.03

Criterion B

Specific evidence creates a designable problem.

Weak

“Students need a better charging station.”

No defined user, task, evidence or opportunity.

Stronger

“Students using the shared station during short passing periods struggle to reach rear ports and confirm connection status…”

Continue by summarizing the evidence and the redesign opportunities without prescribing the final mechanism.

Problem statements define intentions—not final forms.04

Evidence chain

Build the problem statement from evidence

Criterion B explicitly links the problem statement to task-analysis opportunities.

Task analysis

Identify the most important pain points and opportunities.

Persona

Explain why the issue matters to the intended user.

Existing products

Show what current products do well / poorly and where opportunity exists.

Synthesize research

Use qualitative + quantitative evidence to justify the problem.

Write concisely

Current situation + current problem + research summary + design direction.

A problem statement should be explainable from Criterion A.05

B2.1.9

A design specification defines what success must look like.

Specifications are generated from research and communicate the essential and desirable criteria for the redesigned product.

Essential

Must be achieved

Without it, the redesign fails a critical user / functional / safety requirement.

Desirable

Improves the solution

Adds value if feasible but is not as critical as an essential requirement.

Essential vs desirable should be justified by evidence.06

Guide checklist

Consider the categories that actually matter to your product.

Attributesdesired qualities / characteristics

Componentsparts / elements

Constraintslimits / restrictions

Environmentcontext / surroundings

Functionsintended operations

User needsfunctionality, usability, performance

Safetyhazards, harm, legal requirements

Aestheticscolour, shape, texture, style

Manufacturematerials, techniques, assembly

Not prescriptive: do not force every category into every project. Use what is relevant and justify it.

The guide says this list is not prescriptive or exhaustive.07

Criterion B clarification

Specifications must include UX evidence from product analysis and the empathize phase.

Usability evidence

What should improve?

Learnability, efficiency, memorability, errors or satisfaction.

Task evidence

What should become easier?

Reduce a pain point, step, force, error or workaround.

Product evidence

What performance must change?

Translate comparative testing into measurable success criteria.

Criterion A should feed Criterion B.08

Quality test

Replace vague adjectives with evidence-based criteria.

WeakStronger directionEasy to useDefine task success, time, errors, steps or user rating.ComfortableDefine relevant force, contact, posture, dimension or user feedback.SafeIdentify the hazard / standard / condition and how compliance will be tested.Good sizeUse anthropometric evidence, clearance, reach or product constraints.Looks modernDefine evidence-based aesthetic preferences or context if aesthetics are relevant.

A specification should tell you how you will later judge success.09

Apply it

Which specification is strongest?

Research shows the primary persona often carries books in one hand and currently uses two hands to open the product.

Which criterion is most defensible?

Choose before you reveal the feedback.10

Criterion B

Show where each specification came from.

Research finding	Specification	Priority	Future test
Rear port is beyond comfortable reach for shorter users.	All user interaction points within validated reach zone.	Essential	Reach test with intended users.
4/6 users miss colour-only status cue.	Status uses at least two interpretable cues.	Essential	First-use recognition test.
Users prefer minimal desk footprint.	Footprint should remain within agreed area.	Desirable / context dependent	Dimension check + user feedback.

Research → requirement → priority → test.11

IA alignment

Criterion B: Defining the project — 6 marks.

marks

A4 pages

~1200

recommended words

Clarification: approximately 1 page for the problem statement and 3 pages for design specifications. The word count is a recommendation, not a target.

Quality of evidence + explanation matters more than filling space.12

5–6 mark direction

Explain the opportunities and explain the requirements.

Problem statement

Key opportunities informed by task analysis

Links should be explicit and evidence-based, not superficial.

Specifications

Relevant + detailed reference to research

Requirements should be justified, prioritized and traceable.

Do not treat Criterion B as a list-writing exercise.13

20 minutes

Convert three findings into specifications.

Select one ergonomic / anthropometric finding.

Select one usability / task finding.

Select one product-performance / responsibility finding.

For each, write a success criterion, classify it essential/desirable, and state the future test.

Specifications should prepare the testing strategy now.14

Vocabulary lab

Project-definition vocabulary

Retrieve first. Then check.

TermProblem statementClick to reveal

MeaningA concise research-informed statement of the current situation, current problem and design direction.

TermDesign specificationClick to reveal

MeaningA set of success criteria generated from research that defines requirements for the redesigned product.

TermEssential specificationClick to reveal

MeaningA critical requirement the redesigned product must satisfy.

TermDesirable specificationClick to reveal

MeaningA beneficial requirement that adds value but is not as critical as an essential requirement.

TermSuccess criterionClick to reveal

MeaningA condition used to judge whether the redesign achieves its intended performance / user need.

TermConstraintClick to reveal

MeaningA limitation or restriction that affects the design.

TermUser experience (UX)Click to reveal

MeaningThe user’s overall experience of interacting with the product, including usability and response.

TermTraceabilityClick to reveal

MeaningThe ability to connect a design requirement or decision back to relevant evidence.

Say the meaning before you flip the card.15

Knowledge check

Can you retrieve it without looking back?

1. What three elements should Criterion B’s problem statement include?

Current situation, current problem and a summary of research informing the appropriateness of the problem.

2. What two priority types should the design specification capture?

Essential and desirable requirements.

3. What does B2.1.9 require specifications to be based on?

Primary and secondary research, communicating success criteria for the redesigned product.

4. Name three specification categories listed in the guide.

Any three of: attributes, components, constraints, environment, functions, user needs, safety, aesthetics, manufacture requirements.

Say the answer first. Then reveal it.16

Exit ticket

Before you leave…

1. Write one sentence that clearly states your current problem without prescribing a solution.

2. Turn one research finding into a testable specification.

3. Mark it essential or desirable and justify the priority.

Next lesson

IA Day 5 — Criterion A Build Day

Keep the evidence chain moving: user → research → decision → test.

Curriculum alignment
B2.1.8 problem statement · B2.1.9 design specifications · Criterion B: current situation/current problem/research summary + essential/desirable requirements + UX/product-analysis evidence.

Lesson complete17 slides

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IB Design Technology SL · Lesson 2017

Problem Statements &Design Specifications