Criteria for "Easy to Understand" PPT (Based on Standards)

ISO 9241-110: Dialogue Principles for User Interfaces

These principles apply well to presentations:

1. Suitability for the task

   • Content directly supports the presentation goal
   • No irrelevant information
   • Every slide answers "why does the audience need this?"
   • Information depth matches audience expertise level
   • Examples are relevant to audience's context

2. Self-descriptiveness

   • Clear titles and headings on each slide
   • Obvious information hierarchy
   • No need for external explanation
   • Each slide can stand alone if needed
   • Visual cues indicate relationships between elements
   • Legends and labels are always included

3. Conformity with user expectations

   • Consistent layout and navigation
   • Predictable structure
   • Familiar terminology
   • Standard slide templates maintained throughout
   • Industry-standard icons and symbols
   • Logical flow (intro → body → conclusion)

4. Suitability for learning

   • Progressive information disclosure
   • Building complexity gradually
   • Review/summary slides at key intervals
   • Repetition of key concepts in different formats
   • Clear transitions between topics
   • Learning objectives stated upfront

5. Controllability

   • Clear navigation cues
   • Logical slide sequence
   • Slide numbers and section indicators
   • Agenda/roadmap slides for orientation
   • Easy to skip or return to sections
   • Backup slides clearly separated

6. Error tolerance

   • Forgiving of different reading speeds
   • No critical information hidden
   • Important points repeated or reinforced
   • Multiple pathways to key information
   • No reliance on specific slide order for comprehension
   • Verbal explanation can supplement (not replace) visuals

Additional "Easy to Understand" Criteria

Visual Design (ISO 9241-143 & Graphic Design Principles)

• 6-6 Rule: Max 6 bullet points, 6 words per point
  • Prevents information overload
  • Forces presenter to prioritize
  • Keeps text large and readable
  • Encourages verbal elaboration
• Contrast ratio: Minimum 4.5:1 (WCAG 2.1 AA standard)
  • Dark text on light background or vice versa
  • Avoid red/green combinations only
  • Test with grayscale conversion
  • Ensure readability in bright rooms
• Font size: Minimum 24pt for body text
  • Titles: 36-44pt
  • Subtitles: 28-32pt
  • Body text: 24-28pt
  • Footnotes/citations: minimum 18pt
• White space: 30-40% of slide area
  • Margins of at least 0.5 inches
  • Breathing room between elements
  • Prevents cramped appearance
  • Guides eye movement naturally

Cognitive Load Management

• One main idea per slide
  • Clear single message or takeaway
  • Supporting points reinforce main idea
  • Avoid "kitchen sink" slides
  • Use multiple slides rather than crowding
• Limit to 3-5 elements per slide
  • Text blocks count as one element
  • Images/charts count as one element
  • Reduces decision fatigue
  • Follows "magical number 7±2" principle
• Avoid animations that distract
  • Use only purposeful transitions
  • Maximum 1-2 animations per slide
  • Avoid sound effects
  • "Appear" is usually sufficient
  • No spinning, bouncing, or flying text

Accessibility (WCAG 2.1)

• Alt text for images
  • Describe meaningful images fully
  • Mark decorative images appropriately
  • Include data context for charts
  • Ensure screen readers can interpret content
• Color-blind friendly palettes
  • Use color + pattern/texture together
  • Avoid red-green as only differentiator
  • Test with color blindness simulator
  • Use high-contrast color combinations
• Sans-serif fonts for readability
  • Arial, Calibri, Helvetica recommended
  • Avoid decorative or script fonts
  • Consistent font family throughout
  • No all-caps for body text (reduces readability)
  • Adequate letter spacing (tracking)

Pro tip: Test your PPT by the "glance test" - can someone understand the main point of each slide in 3 seconds?