Maartje Boer

THE COURSE OF PROBLEMATIC SMU 201 7 Figure 7.1 Distribution of Problematic SMU Notes. SMU = social media use. The distribution was derived from the complete data on problematic SMU with the data in long format ( n = 3,675 out of 5,676 observations). Respondents were asked howmany times per day they viewed, per week they ‘liked’, and per week they responded to messages, photos, or videos of others on social network sites, such as Facebook, Twitter, Instagram, Google+, or Pinterest (1 never or less than once to 7 more than 40 times ). Respondents were also asked how many times per day they send a message, photo, or video via their smartphone via for example WhatsApp, Chat, SnapChat or SMS (1 less than once to 7 more than 80 times ). Scores on the four items were averaged, such that the score denoted respondents’ mean level of SMU frequency. Cronbach’s alpha ranged between 0.781 and 0.853 across all waves. The original scale includes additional items on the frequency of posting a message, photo, or video on social network sites and checking the smartphone for incoming messages, photos, or videos. Of these two items, the first was excluded because it had a low factor loading ( < 0.500) and the second because removal yielded substantial model fit improvement due to high overlap with the other item on smartphone use ( r = 0.674 to 0.709).