Table 3.

Categories of methods used to evaluate mHealth interventions.

Methods (adopted approaches)	Studies that evaluated mHealth apps	Studies that evaluated mHealth systems
Evaluation of usage logs	[36,38,40-42,44,48,49]	[50,52,54,56-59,62-64]
Standardized questionnaires	[35-39,41-45,48,49]	[35,55-57,60,64]
Ad-hoc questionnaires	[36,37,40,42-44,47]	[51,53,55-58,61-63]
Interviews	[40,45,46]	[50,52,58,59,65]
Clinical outcomes	[36,48]	[54-56,63,64]
Open feedback (ie, oral or written)	[35,41,43,45]	[35,53,62]
Collection of additional device data (eg, medical device data)	N/Aa	[54,56,57,60,62,64]
Field study and observation	[46,47]	[61,65]
Focus groups	N/A	[59,64]
Observational tests (in a lab setting)	[45,47]	N/A
Quality guidelines	[35,39]	[35]
Medical record entries	[42]	[63]
Attendance (intervention assigned activities/meetings)	[42,48]	N/A
Download count	[41]	N/A

^aN/A: not applicable.