Read more on HTA information graphics: Will Stahl-Timmins' PhD Thesis

Information graphic techniques are constructed of visual elements, used to represent data. Sometimes this can be a straightforward transformation, such as the use of a point on a two dimensional map to represent a spatial position. Frequently, however, these representations are abstract, such as the use of different length bars to represent quantities on a bar graph (use of one dimensional sizing, or length).

[IG] elements

Colour (for categorisation)

Colour is often used to categorise information in graphics, as in this example
from Digg Labs.

1D size (length)

The main element used in a bar chart is one-dimensional sizing. The data is represented with the length of the bars. This can be thought of as a transformation from numerical data to 1D size.


One of the most simple methods of displaying quantitative information is to represent it using pictograms, or other objects. See Otto and Marie Neurath's "Vienna Method"
(also known as "Isotype")

Some static elements:

  • 1D position
  • 2D position
  • 3D position
  • 1D size (length)
  • 2D size (area)
  • 3D size (volume)
  • colour (for categorisation)
  • colour (for data)
  • pattern
  • shape
  • orientation
  • count
  • symbol
  • illustration
  • photographs
  • grouping
  • highlighting
  • linking

Some active elements:

  • mouse position
  • 1D object motion
  • 2D object motion
  • 3D object motion
  • user parameter entry
  • user parameter selection
  • user scale
  • user 1D position (sort)
  • user colour
  • user... [insert static element]
  • string matching (search)
  • user selected detail
  • video
  • sound

2D size (area)

Meaning can be given to the size of elements within a graphic. We train ourselves from an early age to estimate the relative sizes
of objects. This fact can be exploited effectively by a skilled designer.

User parameter (selection)

An advantage of computer-based information graphics
is that users can adjust parameters to fit their own
needs and desires.

[IG] HTA - Information Graphics in Health Technology Assessment

The information graphics project at PenTAG, Peninsiula Medical School, researches the use of visual display techniques for presenting research data from health technology assessment.