Active and Passive Social Media Use and Symptoms of Anxiety and Depressed Mood Among Icelandic Adolescents. - Ingibjorg Eva Thorisdottir; Rannveig Sigurvinsdottir; Bryndis Bjork Asgeirsdottir; John P. Allegrante; Inga Dora Sigfusdottir (Cyberpsychology Behav. Soc. Netw., 2019)