Outpatient psychosomatic aftercare after inpatient rehabilitation pursues the goal of helping patients to transfer the achieved rehabilitation result in everyday life and professional life. The Hanover Curriculum has been established as a treatment programme for psychosomatic aftercare. This comprises 25 weekly group sessions and two single therapies at the beginning and at the end of the therapy.

In Germany a vast majority of rehabilitants in a psychosomatic rehabilitation clinic has an indication for psychosomatic aftercare, but it is used only by less than half of the patients due to a lack of aftercare therapists. If there is a therapist in the patient's vicinity, there are often long travelling times to the therapist or the patients might feel stigmatized participating in a face-to-face therapy.

Thus, the expansion of internet-based aftercare services is recommended. Advantages are that they can be carried out at home, possible cost and time savings and improvement of the care situation.

Several meta-analyses provide high evidence for the effectiveness of internet-based therapy offers in depressive and anxiety disorders that are frequent among psychosomatic rehabilitation patients. First randomised controlled studies show that internet-based aftercare services can lead to a symptomatic improvement and to a reduction of relapses. It is currently not clear whether established aftercare concepts, such as the Curriculum Hannover, are also effective in an internet-based format (Curriculum Hannover Online).

The present project consists of a superiority study, examining whether participation in Curriculum- Hannover-Online leads to a stronger adoption and maintenance of the health improvements achieved in inpatient rehabilitation in comparison to care as usual, and an equivalnece study, examining, wether the Curriculum Hannover Online is an equivalent treatment option to the existing face-to-face aftercare therapy.

The use of information and communication technology with the aim of promoting mental health can be described as "e-Mental Health", which is regularly used synonymously with the term "internet-based interventions".

With regard to the study situation on internet-based aftercare interventions, especially in Germany, the research is in an early phase. An overview of the possible uses of internet-based treatment approaches in rehabilitation can be found in Lin, Ebert, Lehr, Berking and Baumeister (2013) and - based on the contributions of the Rehabilitation Science Colloquium since 2008 - Baumeister, Lin and Ebert (2013). However, the first randomised controlled studies on aftercare show, in agreement with the studies outlined above, that corresponding offers led to a reduction in relapses compared to Care as Usual (CAU) (Bauer, Okon, Meermann, Kordy, 2013; Ebert, Tarnowski, Gollwitzer, Sieland& Berking, 2013).Both interventions represent new conceptual developments. Regarding the positive findings on the effectiveness of internet-based interventions and with a view to the suboptimal care situation, Kobelt, Winkler and Petermann (2011), for example, recommend the expansion of internet-based aftercare services and their evaluation.

The planned project aims to develop an internet-based variant of the aftercare concept Curriculum Hannover (Curriculum-Hannover-Online), to integrate it into routine care and to test its effectiveness. The technology of the virtual classroom is particularly suitable for internet-based interventions providing group therapy (cf. Wolever et al., 2012).

For this purpose, the existing manual for Curriculum Hannover (cf. Kobelt et al., 2002) is adapted in the course of the process for the needs of an online intervention. The therapists will be prepared for the specifics of the medium through a train-the-trainer-training for learning how to specifically establish and maintain a therapeutic relationship between therapist and participants. It is assumed that this new program for outpatient aftercare after inpatient psychosomatic rehabilitation can be an effective and useful therpy for patients who do not have access to the existing face-to-face aftercare therapies.. The Virtual Classroom is a direct, video- or audio-synchronous and multimedia contact between therapist and patient.

The main question of the superiority study is:

A. Does participation in the Curriculum-Hannover-Online lead to improved uptake and maintenance of the health improvements achieved in inpatient rehabilitation? B. Can the implementation of the Curriculum-Hannover-Online be designed in such a way that its use as a routine procedure in rehabilitation can be recommended? C. Can the Curriculum-Hannover-Online be accepted by the relevant stakeholders to the same extent as the face-to-face version of the Curriculum-Hannover-Online? For the successful introduction of a new treatment approach, in addition to the proof of its effectiveness, significant challenges have to be overcome with regard to the organisation of work processes, the involvement of all actors involved in the process (especially patients, practitioners, management).

The main question of the equivalence study is:

A.Does participation in the Curriculum-Hannover-Online lead to an equivalent adoption and maintenance of the health improvements achieved in inpatient rehabilitation? B. Can the implementation of the Curriculum-Hannover-Online in addition to the offer of the face-to-face variant be designed in such a way that its use as a rou- tine procedure in rehabilitation can be recommended? C.Can the Curriculum-Hannover-Online be accepted by the relevant stakeholders to the same extent as the face-to-face version of the Curriculum-Hannover-Online? D.Can characteristics be identified that allow a differential indication for the recommendation to participate in the Curriculum Hannover in its online or face-to-face variant? E.What are the additional advantages of the Curriculum Hannover Online from the perspective of patients, therapists, service providers and health care providers? Both studies will be conducted as two-arm randomised controlled trials. Individual rehabilitation patients will be randomised to the respective study arms. The system is based on a randomisation list (permuted blocks of variable length) with the help of the "Randlist" software at the sites. The order of the completed questionnaires determines the position in the list.

All data of the participants will be treated in accordance with the data security regulations (DSGVO), good scientific practice and the ethical requirements. Furthermore, all patients are informed about the project, ethics and data protection in a generally understandable way by a cover letter from their clinic before the treatment. All project staff are obliged to comply with the ethics guidelines and to maintain confidentiality. The pre- and post-data of the patients are combined by means of a personal code, which does not allow any conclusion about the participant.

Inclusion Criteria:

• Patients after psychosomatic rehabilitation
• indication for outpatient psychosomatic aftercare are included in both studies.
• access to a standard PC and broadband internet connection is required (DSL or LTE).

Exclusion Criteria:

Persons who are

• are discharged with a capacity of less than three hours per day on the general labour market,
• receive or have applied for a pension of at least two-thirds of the full pension,
• receive a benefit that is regularly paid until the start of an old-age pension.
• suffering from acute addiction disorder / acute psychosis

Individual participant data (IPD) will not be published. Other researchers are welcome to get in contact with the PI to get access to anonymous data.