Association of Internet Addiction With Nonsuicidal Self-injury Among Adolescents in China

IMPORTANCE Both nonsuicidal self-injury (NSSI), defined as the direct, deliberate damage of one's body tissue without suicidal intent, and internet addiction among adolescents are public health concerns. However, the possible association of NSSI with internet addiction is not well understood. OBJECTIVE To examine the occurrence of internet addiction with NSSI and any sex differences among Chinese adolescents. DESIGN, SETTING, AND PARTICIPANTS A multicenter, cross-sectional, survey study was conducted from February 18 to October 15, 2015, among adolescents aged 11 to 20 years from 343 classes in 45 public high schools across 5 provinces of China. Data analysis was performed from August 1, 2018, to March 1, 2019. EXPOSURES Possible internet addiction and internet addiction. MAIN OUTCOMES AND MEASURES Less-frequent (1-4 times) NSSI and more-frequent (5 times) NSSI were surveyed using the Chinese version of the Functional Assessment of Self-Mutilation. RESULTS A total of 15 623 students (8043 male [51.5%] and 7580 female [48.5%]) aged 11 to 20 years (mean [SD] age, 15.1 [1.8] years) participated. Of these, 4670 participants (29.9%) met the criteria for possible internet addiction and 509 participants (3.3%) met the criteria for internet addiction. A total of 2667 students (17.1%) engaged in less-frequent NSSI, whi