If it’s the smartphone or social media, they asked, then where is the evidence from other countries? It soon began to roll in. Self-harm, anxiety, and depression increased sharply among teens in the United Kingdom, Canada, and Australia. For example, depression rates more than doubled among 13- to 16-year-olds in the United Kingdom, with the sharpest increases after 2010 (see Figure 6.40). These data also help rule out causes that are more specific to the U.S., such as worries around school shootings, or polarization around Trump.
