[Internet therapy. Opportunities and boundaries].

Internet therapy is directed toward people whose access to the usual treatment structures is limited. Further, Internet therapy is aimed at patients with circumscribed psychiatric disorders or symptoms. Compared to usual face-to-face treatment the duration of the Internet therapy programs evaluated were rather short, and frequently only small populations were examined. The studies presented demonstrate that Internet-based therapy of specific disorders is suitable for a significant reduction of symptoms. As follow-up data of longer duration are not available, no concluding statement relating to sustained symptom reduction can be made. Further, it remains unclear whether efficacy of the Internet therapy programs examined is comparable to usual treatment, since only two studies compare Internet therapy with face-to-face treatment.