ixd-standards

9 DfE interaction design principles

Understand ALL users; needs, behaviours and pain points
Design accessibly
Follow Gestalt laws
Reduce cognitve load
Support / prevent users making mistakes
Make users do less
Consider context
Design a seamless experience
Design with data and design logic

As a Clan (team) we have pulled together a set of principles and good practices which we use for Interaction Design to provide consistency and guidance to how we apply design rationale and practices, leading to great interaction design and a great user experience.

We also design our services to meet the government design principles, and the service standard.

Principle 1. Understand all users; needs, behaviours and pain points

…so that we understand all users and their needs with an ambition to meet them.

User needs come in different forms. Designing for information-based and task-based needs will lead to a service/journey which will allow users to complete their task(s) to see an outcome. Understanding behaviour-based needs will improve the experience. It helps us to design how our users use the service. This means we can avoid ‘fudges’ and workarounds users might do to complete a task(s) they need to do.

Good practice for understanding all users

You should:

understand the research insights
use needs-based personas
consider both user needs (including accessibility needs) and business needs
fix or mitigate user pain points
factor in user behaviours
understand ‘how’ the user does xyz
understand ‘why’ the user does xyz
think about what’s missing (to feed into UR/workshops)

Principle 2. Design accessibly from the start

…so that we are inclusive (opens in new tab) (). We need to design and deliver services that work for everyone. Service standard 5 (opens in new tab)

Designing for accessibly from the start reduces rework and time, is morally the right thing to do and is a legal requirement.

We design to meet accessibility standards (opens in new tab)

Legislation

We may be breaking the law if we design services which are not accessible.

The Equality Act 2010 (opens in new tab) covers all public sector bodies.

Good practice for accessibility

You should:

use sufficient background/foreground colour contrast
use industry recommended sizes for interactive components
design structure into pages (headings of different levels, lists…)
visually indicate the page focus
avoid images of text
not represent information using just colour on its own
find pains a user might have using a journey map to understand where the journey/paths are not easy to use by everyone

Principle 3. Follow Gestalt laws

…so that we design for natural human perception.

Gestalt laws are principles which relate to how people naturally perceive visual stimuli, group things together and simplify complex objects. Designers should use these to organise content to maximise natural perception:

Gestalt laws to consider for good practice

You should:

law of proximity
law of closure
law of similarity
law of continuity

Principle 4. Reduce cognitive load

…so that we don’t overload users.

Unnecessary demands being made on users’ mental capacity when completing a task can lead to feeling overwhelmed, anxious and frustrated while increasing mistakes. We should design to support user’s short-term memory capacity and allow them to focus on one task at a time.

Good practice for reducing cognitive load

You should:

prefill data (if/when the user gives consent)
use summary pages to playback to users (give options to go back easily and amend)
make it easy to compare data from different sources
follow Miller’s law (chunking) to help memory limitations
apply progressive disclosure

Principle 5. Support / prevent users making mistakes

…so that users make less errors and can recover from mistakes.

Making mistakes can be frustrating and increase anxiety when users are interacting with a service. To avoid these negative emotions, we should design to reduce the chance of users making mistakes but also for recovery when mistakes do occur.

Good practice for helping users

You should:

allow users to undo actions
provide confirmation of actions - for example, save and delete
provide logical options for checkboxes / radio buttons
think error recovery and error prevention
make users explicity confirm destructive actions. For example, are you sure you want to delete?
add helpful context - for example, use hint text
include helpful validation messages

Principle 6. Make users do less

…so that the experience is faster and easier for users. Service standard 4 (opens in new tab)

A series of additional interactions add up to an experience littered with unnecessary interactions which slow the user down and increase effort. Remove unnecessary interactions when the user can achieve the same goal with less effort and it doesn’t impact on their ability to process information. What seems like small interactions will add up to incremental improvements to the overall experience.

Good practice for making users do less

You should:

pre-populate, auto filter, remove redundancies
avoid unnecessary or extra interactions / provide short cuts
reduce scrolling - for example, use back to top, anchor links
follow Fitt’s law - time relative to size and distance
reduce repetitive interactions

Principle 7. Consider context

…so that we are designing for user’s circumstances and so users understand their circumstances in relation to using the service.

Understanding users’ circumstances helps us to design for their constraints. Providing context helps users to understand where they are and what they can to do next. Provide information and functionality in context - at the point the user is most likely to need it. Save the user hunting for it, or missing it altogether.

All these context related considerations should help manage user expectations, leading to a clearer experience.

Good practice for context

You should:

avoid dead-ends
explain what will happen next
tell users what they need
access to / content at the point users need it
indicate timescales
consider the end-2-end journey
consider environment, IT confidence, pressures and constraints
provide timely system feedback

Principle 8. Design a seamless experience

…so that the user experience is familiar and predictable.

Users learn how a service looks and works as they are using it. By having consistent designs and interactions, we are helping users to learn more quickly, building on their familarity and re-enforcing their mental models of how to interact with the services.

Good practice for designing a seamless experience

You should:

re-use patterns / code where possible and appropriate to conform with user expectations
avoid bespoke designs where possible
make sure systems look / behave the same
maintain documentation e.g. Design histories, design decisions, other IxD dcoumentation

Principle 9. Design with data and design logic

…so that everything is grounded in insights and evidence to provide robust design rationale.

Insights and design rationale are essential to designing services which meet user needs and expectations. As opposed to creating shiny new functionality which confuses users, is unused or even hinders their use of the service.

Good practice for designing with data and design logic

You should:

ensure designs are testing hypothesis
ensure features are fulfilling a user need
ensure design rationale exists for design decisions
follow User Centred Design best practice
remove unnecessary components which are not intent driven or do not add value