Designing for accessibility

User-Oriented Design in Power BI

Maarten Van den Broeck

Content Developer at DataCamp

Color vision deficiency (CVD)

• Affects approximately 8% of men and 0.5% of women
• Two key causes: a deficiency of particular cones in the eye ("anomaly") or the absence of particular cones in the eye ("anopia")

¹ https://en.wikipedia.org/wiki/Color_blindness

Color vision deficiency (CVD)

• Affects approximately 8% of men and 0.5% of women
• Two key causes: a deficiency of particular cones in the eye ("anomaly") or the absence of particular cones in the eye ("anopia")

Name	Cones	Likelihood
Protanomaly	Red	1% Men
Protanopia	Red	1% Men
Deuteranomaly	Green	5% Men
Deuteranopia	Green	1% Men
Tritanomaly	Blue	Rare M/F
Tritanopia	Blue	Rare M/F

¹ https://en.wikipedia.org/wiki/Color_blindness

CVD in action

Typical vision

Tritanopia

Protanopia

Deuteranopia

Tips for better color usage

• Less is more!
• Prefer visuals which do not need to use color as a signal
• Use CVD-friendly color palettes
• Have indicators other than color
• Use tools like Coblis

Font Sizes

High Contrast Mode

Increasing contrast

• Contrast ratio: difference in perceived brightness between two colors
• Recommended at least 4.5:1 for normal text and 3:1 for large text (18 points or larger)
• Background images typically lead to lower contrast ratios
• Use contrast testing tools to check this

Screen readers

• Power BI supports screen readers--tools which speak aloud the text on a page or the "alt text" of an image for users with limited vision
• Power BI supports showing a visual as a table, making it easier for a reader to list values
• Alt Text describes the visual and can be based on static text or the value of a field
• Keyboard shortcuts are limiting and screen readers don't read all contents.

Smart narratives

Our audience

• Research organization looking to understand inflation trends
• Report users may have visual accessibility concerns

Let's practice!

User-Oriented Design in Power BI