Table 1.

Outline of the usability testing strategy

Step	US center	German center
1	Introduction and background interview
2	75% received a 15–20-minute training session, 25% received no training	100% received training and then immediately commenced the test session
3	Trained patients waited for at least 2 hours before commencing the test session
4	Set dose memory
5	Preparation of pen (insertion of cartridge)
6	Preparation of pen (attach needle and needle hider)
7	Injection procedure
8	Disassembly
9	No drug wastage system including cartridge exchange
10	Closing interview