Critical Design Strategy (CDS)

The heuristic questions

The second stage of the Critical Design Strategy (CDS) involves a comprehensive critique of the visualisation artefact through a structured set of heuristic questions. These questions are designed to guide the appraiser through six key perspectives:

1. User – suitability, trustworthiness, usefulness, and clarity of the visualisation from the perspective of the intended audience.
2. Environment – how well the artefact fits its physical and technological setting.
3. Interface – usability, ergonomics, and the layout of visual and interactive elements.
4. Components – presence and quality of the visualisation’s core parts and their interrelationships.
5. Design – aesthetic quality, spatial organisation, and clarity of context.
6. Visual Marks – effective use of visual encoding, appropriate abstraction, and clarity of display.

Each perspective contains five targeted heuristic questions (30 in total). These are not mere checklists but prompts for reflective analysis.

Each of the following 30 heuristic questions is scored on a Likert scale from -2 (poor) to +2 (excellent). They are grouped into six perspectives that help appraisers think broadly and deeply about their visualisation design.

The purpose of each heuristic is to (i) encourage systematic and deep reflection, (ii) help people avoid overlooking important design or usability factors, (iii) support the development of design literacy and critical awareness and (iv) enable tracking of improvement over iterations.

For each heuristic, select a rating from –2 (very poor) to +2 (very good). Consider the context: who the users are, what the data represents, and how the visualisation is to be used. Where possible, add brief notes to support your judgment. Do not worry about being overly precise as the Review stage will help refine and reflect on these initial ratings.

This isn't about ticking boxes, instad it's about thinking critically. Use the heuristics to identify strengths and weaknesses, surface design issues, and articulate your reasoning. This analysis sets the foundation for reflection in the final stage.

User

• Is it suitable for the user and task?
• Is it understandable for the task at hand?
• Does it avoid requiring guesswork?
• Is it trustworthy?
• Would it be useful?

Environment

• Does it fit with other technologies?
• Is the technology suitable?
• Is interaction appropriate for the context?
• Is its size appropriate for the setting?
• Does it give a positive ambience?

Interface

• Is the GUI suitable?
• Is it ergonomic and comfortable?
• Are facets sized suitably?
• Is spacing appropriate?
• Is the number of interface parts suitable?

Components

• Are all necessary components included?
• Are all output/view types suitable?
• Are relationships between parts clear?
• Can the task be performed easily?
• Is the layout of components appropriate?

Design

• Is the design inspiring?
• Is it visually attractive?
• Is space used effectively?
• Is data coverage appropriate?
• Are legends, labels, and instructions clear?

Visual Marks

• Are channels well-chosen to communicate clearly?
• Are relationships mapped appropriately?
• Are mark types suitable?
• Is the level of detail/abstraction appropriate?
• Is anything hidden that shouldn’t be?

Stage 2: Detail — Heuristic Evaluation Table

Rate each heuristic using the scale from -2 to +2. Use the guiding labels on the right to help your judgment.

Total Score: 0

Perspective	#	Heuristic Question	Rating (-2 to +2)					Range of Answers
User	1	Is suitable for the user and task	-2 -1 0 1 2					Poor ↔ Good
User	2	Is understandable for user and task to hand	-2 -1 0 1 2					Poor ↔ Good
User	3	It doesn't require guesswork	-2 -1 0 1 2					Poor ↔ Good
User	4	Is trustworthy	-2 -1 0 1 2					Poor ↔ Good
User	5	Would be useful	-2 -1 0 1 2					Poor ↔ Good
Environment	6	It would fit in with other technologies	-2 -1 0 1 2					Poor ↔ Good
Environment	7	Uses suitable technology	-2 -1 0 1 2					Poor ↔ Good
Environment	8	Has appropriate interaction	-2 -1 0 1 2					Poor ↔ Good
Environment	9	Its sizing is correct	-2 -1 0 1 2					Poor ↔ Good
Environment	10	Gives a positive ambience	-2 -1 0 1 2					Poor ↔ Good
Interface	11	Suitable user interface	-2 -1 0 1 2					Poor ↔ Good
Interface	12	Ergonomic interface	-2 -1 0 1 2					Poor ↔ Good
Interface	13	Facets are sized suitably	-2 -1 0 1 2					Poor ↔ Good
Interface	14	Interface suitably spaced	-2 -1 0 1 2					Poor ↔ Good
Interface	15	Suitable quantity of interface parts	-2 -1 0 1 2					Poor ↔ Good
Components	16	Has all necessary components	-2 -1 0 1 2					Poor ↔ Good
Components	17	Has all suitable output/view types	-2 -1 0 1 2					Poor ↔ Good
Components	18	Clear relationships between parts	-2 -1 0 1 2					Poor ↔ Good
Components	19	Task can be easily performed	-2 -1 0 1 2					Poor ↔ Good
Components	20	Suitable organisation of components	-2 -1 0 1 2					Poor ↔ Good
Design	21	Inspiring design	-2 -1 0 1 2					Poor ↔ Good
Design	22	Aesthetic and visually attractive	-2 -1 0 1 2					Poor ↔ Good
Design	23	Good composition and space utilisation	-2 -1 0 1 2					Poor ↔ Good
Design	24	Suitable coverage of data/underpinning facets/concepts	-2 -1 0 1 2					Poor ↔ Good
Design	25	Clear instructions, labels, legends to give context	-2 -1 0 1 2					Poor ↔ Good
Visual marks	26	Right choice of channels to communicate things clearly	-2 -1 0 1 2					Poor ↔ Good
Visual marks	27	Communicates appropriate relationships/morphisms	-2 -1 0 1 2					Poor ↔ Good
Visual marks	28	The types of marks used, communicate things well	-2 -1 0 1 2					Poor ↔ Good
Visual marks	29	Components are shown at the right level of abstraction/detail	-2 -1 0 1 2					Poor ↔ Good
Visual marks	30	Nothing is hidden that shouldn't be hidden	-2 -1 0 1 2					Poor ↔ Good