Table 1.

Summary of autoinjector features

Design principle	Features
Easy to use The device should be easy to manipulate, with different ways of holding or interacting with it for patients with a range of physical abilities	• Large dose button • Wide body diameter with textured surface • Large base cap • Triangular base keeps device stable vertically or horizontally during storage
Easy to understand The device operation should be intuitive with minimal steps	• Wide flared base allows device to be held stably at the point of injection and eliminates the need for pinching up the skin or to use a specific injection angle
Easy dose confirmation Patients should feel confident that they are using the device appropriately with confirmation that they are successfully delivering their dose	• Clear base allows visualization of the injection site and drug solution • Audible clicks at the beginning and end of the injection provide auditory confirmation of dose delivery
Safe to use The device can be safely used and disposed of	• Easy-to-move lock prevents misfiring of the device • A needle that retracts after the injection is complete