Table 1.

Deductive coding system

Sensor – needs and preferences related to	Smartphone – needs and preferences related to	App – needs and preferences related to
Color	Operating distance	Design colors/information
Size/shape	Triggering/alerting process	Option “stop alert”
Weight	Messaging in context of alerting	Option “need help”
Material	Contacts of alert	Use (feasibility and practicability)
Body location	Use (feasibility and practicability)
Duration of wearing
Fixation on body
Use (feasibility and practicability)