The 7 level approach
One of the most straightforward approaches to design states that there are three principal stages of design:
These stages apply to all design processes, whether designing product interfaces, telephone handsets or design approaches. In order to include social and practical acceptability, we have extended these three stages into a 7-level design approach.
Although the 7-level approach is presented as a flow diagram, each of the stages can be applied in an iterative manner. Indeed, in many circumstances, it may prove essential to iterate within, and between, levels. However, the general order of application of the levels should be as shown in the figure.
If the 7-level approach has been adopted as the framework for the development, then the inclusive design cube can be adopted to monitor the population coverage achieved by different design choices. Effectively, the 7-level approach can be thought of as designing for each axis on the IDC. The modification necessary to use the IDC for system definition is a straightforward re-labelling of the axes to reflect Levels 3 to 5 of the 7-level approach (see figure opposite).