Table 4.

Barriers to and facilitators of using HeadOn based on qualitative interviews.

Intervention characteristic	Facilitators	Barriers
Intervention engagement	Family support Weekly email reminders Logging in via emails Building a routine Setting own reminder Easy to use Symptom burden Motivation to recover and belief intervention was supporting recovery Credible source Days in a row Flexibility of intervention being digital and self-directed COVID-19 pandemic improved digital literacy Being part of academic study Saved to home screen on device	Forgetfulness and memory High symptom burden after concussion Difficulty with screens and devices or digital Low symptom burden Difficulty registering Work or other commitments Not enough prompts to log in (notifications, emails, SMS text messages, and calendar reminders) Not a native app and log-in process
Information	Credible source Audio or transcript available	Difficulty with screens Difficulty concentrating
Symptom monitoring	Days in a row Ability to review progress	Repetitive Main symptom not included Progress review limited to 7 days
Exercise and lifestyle	N/Aa	Alcohol tracker lacking ability to go back or take off units
Thought monitor	N/A	Language used did not resonate with participants or they did not feel it suited their situation Memory loss of injury Repetitive task Emotions not an issue
Technical and design	Easy to navigate Simple design Instructions Audio or text files	Registration Difficulty logging in Difficulty with screens

^aN/A: not applicable.