Adolescents with depression often experience negative automatic thoughts, which contribute to the development of suicidal ideation. Internet-based cognitive behavioral therapy has now become a treatment to address negative automatic thoughts to prevent suicide. This quasi-experimental study aimed to assess the effects of an Internet-based Cognitive Behavioral Therapy Program on the depression of Thai adolescents. The participants consisted of 60 adolescent students with a deviation from their usual mood who were enrolled in public high schools in a province adjacent to Bangkok. The participants were conveniently selected, paired based on gender and grade point average, and randomly assigned into two groups. The experimental group received the program, while the control group received usual care (n = 30 each). Data collection instruments included a personal data form and the Healthrelated Self-report Scale. One-way repeated measures ANCOVA was used to compare the mean depression scores between the two groups while controlling for baseline depression scores.
The results indicate that the participants’ depression scores decreased over time in both groups. However, a significant group effect suggests that being in the experimental group was associated with a greater decrease in depression scores both immediately after the intervention and at the two-week follow-up compared to the control group. These findings shed light on the potential benefits of implementing this Internet-based Cognitive Behavioral Therapy Program by school nurses, teachers, or primary care nurses to prevent extreme depression and suicidal ideation among adolescents. Further investigation with longer follow-up is recommended.