Background and aimsInstances of Internet use disorders (IUD) including Internet gaming disorder (IGD) and non-gaming pathological Internet use (ng-PIU) have the extent that they are now a growing mental health issue. Individuals suffering from IUD show a large range of symptoms, high comorbidities and impairments in different areas of life. To date there is a lack of efficient and evidence-based treatment programs for such adolescents. The present registered single-arm trial (ClinicalTrials.gov: NCT03582839) aimed to investigate the long-term effects of a brief manualized cognitive behavioral therapy (CBT) program for adolescents with IUD.MethodsN = 54 patients (16.7% female), aged 9–19 years (M = 13.48, SD = 1.72) received the CBT group program PROTECT+. IUD symptom severity (primary outcome variable) as well as comorbid symptoms, risk-related variables and potentially protective skills (secondary outcome variables) were assessed at pretest, posttest, as well as 4 and 12 months after admission.ResultsPatients showed a significant reduction in IUD symptom severity at the 12-month follow-up. Effect sizes were medium to large depending on the measure. Beyond the statistical significance, the clinical significance was confirmed using the reliable change index. Secondary outcome variables showed a significant reduction in self-reported depression, social anxiety, performance anxiety and school anxiety as well as in parental-reported general psychopathology.Discussion and conclusionsThe present study shows long-term effects of a manual-based CBT treatment for adolescents suffering from IUD. The results indicate that even a 4-session brief intervention can achieve a medium to large effect over 12 months. Future work is needed to confirm the efficacy within a randomized controlled trial (RCT).

IMPORTANCE Behavioral addictions were introduced as novel mental disorders in the InternationalClassification of Diseases, 11th Revision, based on evidence that human behavior itself can become addictive, similar to addiction to substances. However, previous studies on prevention of gaming disorder and unspecified internet use disorder lacked randomization, follow-up measurements, and diagnostic interviews that assessed incidence rates; this trial was intended to fill this gap. OBJECTIVESTo investigate whether the PROTECT (Professioneller Umgang mit technischen Medien [Professional Use of Technical Media]) intervention can reduce the symptom severity and prevent full syndrome and subthreshold onset of gaming disorder and unspecified internet use disorder in at-risk adolescents. DESIGN, SETTING, AND PARTICIPANTS A multicenter cluster randomized clinical trial conducted recruitment, screening, intervention delivery, and data collection among at-risk adolescents aged 12 to 18 years in 33 high schools in Germany. Inclusion criteria for the study and symptom severity analyses were elevated symptoms of gaming disorder and unspecified internet use disorder. A subsample that met the inclusion criteria for incidence analyses (no full syndrome of gaming disorder or unspecified internet use disorder, depression, or anxiety at baseline) was analyzed for illness onset. Participants were randomized to either the PROTECT intervention group or the assessmentonly control group. Participants were assessed at baseline, 1-month follow-up, 4-month follow-up,

Internet Use Disorder (IUD) affects numerous adolescents worldwide, and (Internet) Gaming Disorder, a specific subtype of IUD, has recently been included in DSM-5 and ICD-11. Epidemiological studies have identified prevalence rates up to 5.7% among adolescents in Germany. However, little is known about the risk development during adolescence and its association to education. The aim of this study was to: (a) identify a clinically relevant latent profile in a large-scale high-school sample; (b) estimate prevalence rates of IUD for distinct age groups and (c) investigate associations to gender and education. N = 5387 adolescents out of 41 schools in Germany aged 11–21 were assessed using the Compulsive Internet Use Scale (CIUS). Latent profile analyses showed five profile groups with differences in CIUS response pattern, age and school type. IUD was found in 6.1% and high-risk Internet use in 13.9% of the total sample. Two peaks were found in prevalence rates indicating the highest risk of IUD in age groups 15–16 and 19–21. Prevalence did not differ significantly between boys and girls. High-level education schools showed the lowest (4.9%) and vocational secondary schools the highest prevalence rate (7.8%). The differences between school types could not be explained by academic level.