Here is an interesting example of use patterns impacting results:

The Pecan Research Institute ran a study in which they analyzed electricity generation by solar panels that a) faced south and b) faced west. Most solar panels are mounted to face south because that orientation maximizes the number of hours of sunlight the panels can receive. What the study showed, however, was that west-facing panels actually generated 2% more electricity over the course of a day. More importantly though, during periods of peak demand, west-facing panels generated 49 percent more electricity than south-facing panels. In Austin, where the study was conducted, peak electricity usage is between 3 and 7 pm – basically when the sun is in the west.

The take-away for medical product design is that products need to be designed within the framework of their patterns of use. Solar panels are more effective when mounted with peak electricity usage in mind. Using a similar principle, medical products can be designed to be more effective if the designer analyzes the product’s most important tasks/functions and how the user will be interacting with the product and environment when the critical tasks/functions need to be employed.