Cognitive Accessibility Design Pattern: Use Familiar Metrics and Units
I need interfaces to use metrics I know, and that are common in my location (such as feet or meters) otherwise I get confused. I do not always know what metric they are talking about or notice that the number looks wrong.
What to Do
Provide metrics in units that users will be familiar with.
How it Helps
Most people are familiar with a single set of units that are commonly used for metrics in their location or culture. When the metrics are in other units they need to perform a conversion in order to understand them. Even tools such as a calculator can be hard to manage. Provide an option to change units and default the units to the users’ location. Common examples are the units used for distance, weight, area, currency, and temperature.
For example, a user may know the temperature in Centigrade. When it is given in Fahrenheit, they think it is going to become very warm.
Sometimes metrics are commonly declared in a specific unit even when localized alternatives are available. For example, TV or monitor sizes are usually given in inches even when centimeters are the common unit. However, even, in these cases, providing alternatives are still useful as users may not be familiar with the metrics given.
Provide a mechanism to select a different set of metrics that are more meaningful to the user, or provide common alternatives in the text
- Metrics in different units that different users understand. For example:
- The Eiffel Tower is 1,063 feet (324 meters) tall, including the antenna at the top.
- Only one unit for metrics. For example:
- The Eiffel Tower is 1,063 feet tall.
User Stories and Personas
- Alison : An Aging User with Mild Cognitive Impairment
- Gopal : A Retired Lawyer with Dementia
- Jonathan : A Therapist with Dyscalculia
- Kwame : A Traumatic Brain Injury Survivor
- Maria : A User who has Memory Loss
- Sam : A Librarian who has a Hemiplegia and Aphasia
- Tal : A Student who has Dyslexia and Impaired Eye Hand Coordination
- Yuki : A Yoga Teacher who has AD(H)D