Table 2.

Descriptions and examples of social media–related outcomes to be extracted from studies.

Outcomes	Descriptions	Examples of measures
Exposurea	Views of social media content	Campaign awareness, number of views (engagement with content, eg, watching videos), impressions (number of times digital content is displayed regardless of whether it is clicked or not)
Reach	Interaction with social media content and users’ characteristics	Followers, demographics of users
Low-level engagement	Agreement with the social media content	Number of likes for posts
Medium-level engagement	Users creating or sharing their own social media messages or sharing campaign messages on their own profiles	Number of posts or retweets
High-level engagement	Users’ understanding of the messaging, intention to change their behavior, or actions taken on social media or offline related to the desired behavior change	Mental health knowledge and literacy, attitudes or beliefs about mental health stigma, for example, desire for social distance, behavior change: seeking help for mental health, activities for positive mental health, and help-seeking intentions

^aExposure, reach, and low-, medium-, and high-level engagement were measured using a version of key performance indicators and metrics related to social media use in health promotion adapted from Neiger et al [26].