Day clinic and inpatient psychotherapy of depression (DIP-D): qualitative results from a randomized controlled study

Objective Depressive disorders are among the most common psychiatric disorders. For severely depressed patients, day clinic and inpatient settings represent important treatment options. However, little is known about patients’ perceptions of the different levels of care. This study aimed to obtain an in-depth analysis of depressive patients’ experiences of day clinic and inpatient treatment in a combined clinical setting. Methods Following a randomized controlled trial comparing day clinic and inpatient psychotherapy for depression (Dinger et al. in Psychother Psychosom 83:194–195, 2014), a sample of depressive patients (n = 35) was invited to participate in a semi-structured interview during an early follow up 4 weeks after discharge. A qualitative analysis of interview transcripts was performed following the principles of constructivist thematic analysis. Results Following analysis, 1355 single codes were identified from which five main categories and 26 themes were derived for both groups. In regard to patient group integration and skill transfer to everyday life, distinct differences could be observed between the day clinic and inpatient group. Conclusion While adjustment to therapeutic setting and patient group integration seem to be facilitated by inpatient treatment, the day clinical setting appears to promote treatment integration into patients’ everyday contexts, aiding treatment-related skill transfer to everyday life as well as alleviating discharge from clinic treatment. Further studies on depressive subject groups in day clinic and inpatient treatment should investigate aspects of group cohesion and treatment integration in relation to therapeutic outcome.


Background
With a life-time prevalence rate of up to 24 % for major depressive episodes [1][2][3], depressive disorders are among the most common psychiatric disorders. For affected patients, depressive disorders are associated with a significant impairment of mental and physical quality of life [4] as well as with high psychological strain including suicidal behavior [5,6]. Day clinic and inpatient treatment settings offer important therapeutic options for severely depressed patients. However, little is known about the patients' perception of the different levels of care [7]. Especially qualitative studies providing an indepth analysis of patients' views of day clinic and inpatient psychotherapy are rare, despite offering important insight beyond quantitative questionnaire analysis, [8].
Due to a lack of comparative studies, differential indications and recommendations for day clinic versus inpatient treatment still rely on expert opinion [9]. In its current practice, inpatient psychotherapy is an effective way of treatment for a variety of psychiatric and psychosomatic disorders [10][11][12]. In German healthcare, indications for inpatient treatment include considerable symptom severity, suicidal risk, an inability to function [9,13,14], severe social and domestic conflicts, and a nonresponse to outpatient treatment services.
Day clinic treatment offers several advantages that may explain its growing popularity. The commonly recognized main advantage of the day clinic treatment setting, namely the possibility of providing patients with a combination of intense, multimodal treatment while keeping continuous contact to their home environment and everyday stressors, is at the same time one of its most difficult challenges [13]. The avoidance of inpatient hospitalization not only prevents costs, but introduces an early focus on the reintegration into society. Accordingly, the time division between therapy and the home environment ("half-and-half '') allows patients to maintain social contacts [15], and to continue to care for children and relatives, if necessary [9]. This is in line with treatment models focusing on recovery oriented mental health care [16]. The principle of maintaining close contact to the patients' home environment and stressors may also facilitate the transfer of therapeutic insight to their normal course of life [14]. Furthermore, the day clinic setting may prevent patient-therapist dependency and inhibit an 'escape into hospital' [14], as well as alleviate therapy discharge and re-entry to life outside of the hospital [13]. Accordingly, and in light of the growing economic interest in more cost-efficient treatment options [17], the number of day clinic psychotherapy facilities is increasing [13,18,19]. Finally, the multimodal approach allows for very intensive treatment within a relatively short time frame.
So far, most studies examining differences of day clinic and inpatient psychotherapy have investigated mixed patient samples. Lischka et al. [20] assessed patients' social relationships and their impact on day clinic and inpatient treatment. They were able to show that patients living in non-single households preferred day clinic treatment and that relationships were perceived as more supportive at the end of treatment across settings. In a non-randomized trial, Zeeck and colleagues compared predictors of therapeutic outcome in day clinic and inpatient psychotherapy for a mixed patient group [21]. For day clinic therapy, better outcomes were associated with higher motivation and burden at home, while inpatient outcomes were less favorable if patients' symptoms were triggered by situations at home. Furthermore, inpatients showed the tendency to foster wishes of being taken care of, thereby increasing dependency at the cost of more autonomous coping with one's life. In addition, greater patient-therapist dependency was correlated with a less favorable treatment course for inpatients [21].
While most clinical trials focus on symptomatic outcome parameters, qualitative studies offer the possibility of obtaining more detailed impressions of patients' perceptions of different psychotherapy phases. In a qualitative analysis of patients' answers to open interview questions, a high acceptance of both day clinic and inpatient treatment, with a slight preference for the day clinic setting, could be shown [22]. A study on day clinic and inpatient psychotherapy using semi-structured interviews revealed that day clinic patients saw the facilitated transfer to everyday life as the most valuable element of their setting [8]. Patients with alcohol addiction saw the day clinic setting's support of their personal autonomy as particularly beneficial [23]. However, as the stated qualitative studies were no randomized controlled trials (RCTs), inpatient and day clinic samples are not comparable. Furthermore, we are not aware of any previous qualitative studies focusing on depressed patients' experiences of day clinic and inpatient psychotherapy.
Following a randomized-controlled trail comparing day clinic versus inpatient psychotherapy for depressed patients [24,25], the aim of the present study was to obtain an in-depth analysis of depressive patients' experiences with differing levels of care, as patients' subjective experience and definition of treatment success may differ from the type of changes that are captured by standardized questionnaires [26]. Therefore, all patients recruited in the abovementioned study were invited to participate in a semi-structured interview during an early follow up 4 weeks after discharge.

Participants and procedure
The study was conducted between January 2011 and July 2012. A detailed description of the screening process, the diagnostic assessment and the randomisation procedure can be found elsewhere [24,25]. Patients were included in the study if they were diagnosed with a current major depressive episode (MDE) or dysthymia, were aged between 18 and 60, and lived within 60 km of the treatment hospital. Exclusion criteria were acute psychotic or bipolar disorder, addiction with current substance abuse, borderline personality disorder, anorexia nervosa, other eating disorders with a binge frequency of more than three times per day and a clinical indication for outpatient psychotherapy. In order to be representative for routine clinical practice, no specifications regarding psychopharmacological medication were made for this study. In total, 44 patients meeting the selection criteria agreed to participate in the randomized trial. After randomization, patients were admitted either to day clinic or inpatient psychotherapy and treated with multimodal psychotherapy for 8 weeks. After waiting-list and during-treatment dropouts, 35 completers (17 day clinic, 18 inpatients, correspondent to 77.3 % completer rate in the day clinic group and 81.8 % completer in the inpatient group) remained for the follow-up assessment 4 weeks following hospital discharge (12 weeks after admission). At 4 week follow-up, all completers participated in a semi-structured interview on their experience of day clinic and inpatient psychotherapy.

Ethics
The study was conducted following the Code of Ethics of the World Medical Association (Declaration of Helsinki 6th revision, 2008) and registered at the German Clinical Trials Register (DRKS00000550). Written informed consent was obtained from all participants as approved by the local Ethics Committee of the University of Heidelberg (No. S-013/2010).

Treatment
The study took place in the psychotherapy unit of the Department of General Internal Medicine and Psychosomatics at the University of Heidelberg. Combining day clinic and inpatient treatment, half of the patients on the unit are treated in the day clinic setting while the other half receives inpatient therapy. Within the German health care system, intensive hospital-based psychotherapy treatment (i.e. both inpatient and day-clinic) is indicated after failed previous outpatient treatment attempts and/or in the case of special severity requiring hospitalization. Typically, patients are admitted in the context of an exacerbation posing a threat to their longterm social or economic functioning. All group therapies comprise 50 % inpatient and 50 % day clinic patients. Accordingly, both patient groups are treated by the same therapeutic staff and therapists and receive an equal amount of psychotherapeutic interventions per week. Inpatients stay in one-to-three-bed rooms and are free to leave the unit outside of night hours (11 p.m.-6 a.m.), meal times and therapy sessions. Over the treatment period of 8 weeks, inpatients usually spend 6 weekends at home in order to remain in contact with their home environment. Day clinic patients attend therapy on 5 weekdays from 8 a.m. to 4 p.m. They share one meal (lunch) with their fellow inpatients during the day. In addition to the common rooms open to all patients, they are able to retreat to a quiet room between therapy sessions. Outside of day clinic hours, they may call the therapy unit in times of need or emergency at all times.
Following a primary psychodynamic orientation, treatments are carried out in a multimodal psychotherapy setting with integrated cognitive-behavioral, and systemic treatment components. Patients in this study received individual psychotherapy (1/week), psychodynamicinteractional group psychotherapy (2/week), art therapy (2/week), music therapy (1/week), body-oriented therapy (1/week), social competence training (1/week), and systemic sculpture group psychotherapy (1/week). In addition, couple or family sessions were optional. Scheduled therapy sessions were complemented by weekly psychotherapeutic ward rounds, regular contacts with assigned nurses, daily morning and evening groups led by the therapeutic staff, and individual social counselling.

Development of leading questions
In line with the COREQ checklist [27], the development of the study's interview questions and hypotheses was performed on the basis of an in-depth literature review as well as discussion among a team of experts (N = 5; 2 female, 3 male, all of whom experienced in psychotherapy training and research). The interview manual was constructed in a semi-standardised manner [28][29][30][31] containing the main open questions followed by encouraging and clarifying questions if required. In accordance with Helfferich [28], the leading questions referred to day clinic-and in-patients' perceived advantages and disadvantages of their respective setting, patient group integration, treatment success, effects on partnerships, family, social environment, and their occupation as well as achieved skill transfer to everyday life. Following the semi-standardised interview manual, individual faceto-face interviews were audio-taped and conducted by a trained, female interviewer supervised by an experienced tutor and colleagues who had conducted similar studies.

Qualitative content analysis and statistical analysis
For qualitative analysis, we implemented a constructivist thematic analysis approach. The constructivist approach implies that existing relevant literature, e.g. comparative studies on inpatient and day clinic treatment [21], influences research question development and that the resulting sensitisation primes ensuing data analysis. Thematic analysis (TA) is a pragmatic approach to qualitative analysis focusing on the search for identifiable themes across a dataset [32]. Although it draws on some techniques of grounded theory [33,34], TA follows a six-phase analysis process allowing more flexibility and alleviating adaption to specific study affordances. After verbatim transcription, open line by line coding of all 35 interviews was conducted to identify recurring topics. Specific sentences (or combinations of sentences) were identified as a code representing the most elemental unit of meaning [35]. The assignment of codes to specific themes was conducted by two independent analysts (CN and JH) using the software MaxQDA (2010 version, VERBI GmbH, Berlin), discussed to reach consensus and adjusted if necessary. Themes were compared and adapted, until overarching relevant themes for both groups (day clinicand in-patients) could be defined. In a final step, themes were summarized into five relevant categories. In order to identify commonalities and differences between the two participant groups, all codes were analysed for each theme comparing meaning and frequency, and consolidated through a profound expert team discussion. In a final step, topics that were more pronounced among day clinic-vs. in-patients were identified. Descriptive quantitative data were managed with the software package SPSS (IBM SPSS Statistics 20) and presented as mean ± standard deviation (SD) and median with interquartile range as applicable.

Participant characteristics
Thirty-five participants consented to participate in the study on a voluntary basis (50 % female; aged: 35.1 ± SD 11.6 years; range 18-55). The main diagnosis for thirtyfour patients was a MDE and one patient was primarily diagnosed with dysthymia. The comorbid axis-1 diagnoses, in accordance with the structured clinical interview for diagnostic and statistical manual for mental disorders (DSM-IV; SCID), included anxiety disorders (45.5 %), somatoform disorders (13.6 %), dysthymia (11.4 %), eating disorders (11.4 %) and obsessive-compulsive disorders (6.8 %). In addition, 33.3 % of included patients suffered from a personality disorder. Further details can be found elsewhere [24,25].

Main categories and themes
The qualitative analysis of the interviews identified 1355 single codes, from which five main categories and 26 themes were derived for both groups. Table 1 provides an overview of the main categories and themes as defined below for the day clinic and the inpatient group. The number of codes per category and theme is shown in parentheses. Illustrative quotations for main categories and themes are listed in Tables 2 and 3 for each group.

Therapeutic aspects (266)
D.1.1. Adjustment to the therapeutic setting (29) Adjustment to the therapeutic setting was challenging for day clinic patients, who described experiencing difficulties in integrating themselves into the patient community as well as in beginning with the therapeutic process. In retrospect, day clinic patients felt that they had to invest a high degree of energy and initiative to integrate themselves into the pre-existing patient community. Especially patients, who had already been in hospital treatment for several weeks, were perceived as very reserved towards the new arrivals. Day clinic patients attributed early difficulties in socializing to individual personality factors and initial inhibitions towards the group. Furthermore, inhibitions in engaging in therapy and self-disclosure during group therapy were described. Particularly non-verbal treatment sessions, such as music and art therapy, were often initially perceived as disconcerting and potentially shame-inducing.
I.1.1. Adjustment to the therapeutic setting (20) Overall, inpatients experienced fewer difficulties in adjusting to the therapeutic setting, reporting easy integration into the patient community and less inhibitions towards therapy engagement and self-disclosure during group therapy. Facilitated by a welcoming atmosphere and active efforts towards their integration by the unit's existing patient community, most inpatients adjusted easily to the clinic setting. Especially periods between and after scheduled therapy sessions were seen as valuable opportunities for socialization and beneficial for their group integration. Compared to day-clinic patients, inpatients felt that their setting allowed them to experience therapy more intensely. However, some inpatients also described general difficulties in adjusting to the new environment, engaging in therapy and in opening up in front of other patients. Some also reported non-verbal treatment sessions, such as concentrated movement and art therapy, to be initially disconcerting and potentially shame-inducing.

D.1.2. Experience of therapy (61)
Most day clinic patients experienced treatment as beneficial, especially if they felt to have gained a better understanding of the relationship between their biography and current behaviors and emotions. Above all, patients described the body-oriented and the couple therapy sessions as well as the 'safe haven' experience in the hospital, giving them a stabilizing, regular daily structure, as highly beneficial. However, day clinic patients also experienced treatment as stressful listing the confrontation with intensely negative and painful emotions in the therapeutic process, as well as difficulties in learning new means of articulating concerns and needs, as reasons. Most patients felt supported by the units' therapeutic team and described the majority of therapeutic relationships as warm and emotionally close. However, more reserved relationships and difficulties in building up trust were pointed out in some cases.

I.1.2. Experience of therapy (98)
Inpatients experienced therapy as predominantly beneficial and reported an improvement of depressive symptoms. The possibility of being able to spend all day in the unit and the regular daily routine was seen as particularly positive and was reported to facilitate personal activity. However, some inpatients also described difficulties in adhering to the treatment plan, which was experienced as intense and demanding with little time for relaxation. In addition, resurfacing emotions during therapy, as well as self-reflection and intended behavioral changes, were perceived as stressful.
Although some patients described difficulties in building a warm and trusting relationship with therapists and nurses, relationships with the therapeutic team were predominantly perceived as benevolent and emotionally close.

D.1.3. Involvement of current domestic conflicts in therapy/ therapy focus on social and domestic reality (21)
Day clinic patients perceived the continuous contact with everyday life routines and hassles as very autonomy-supportive and beneficial for their re-integration into everyday life after hospital discharge. In particular, the possibility to directly address interpersonal conflicts during evenings at home on the following day was seen as a significant advantage of the setting. Moreover, patients reported that they were able to directly test new skills and behaviours at home and discuss encountered difficulties during therapy the next day. (37) Inpatients described their experience of the hospital as a 'safe haven' , shielding them from their home environment and daily hassles during the entire day, as extremely relieving and beneficial. Patients perceived the setting to allow them to focus on their own difficulties and needs more intensely and felt they were able to more fully engage themselves in the therapeutic process in consequences. (19) Day clinic patients reported to have gained more confidence in dealing with people. In addition, they felt that the positive feedback and appreciation by fellow patients had increased their self-confidence. Moreover, patients experienced the group as a positive space in which they were able to test different or new interpersonal behaviors, such as putting down boundaries by "saying no" or self-disclosing and were thus able to overcome social anxiety or inhibitions. (19) Inpatients felt to have improved their self-esteem through interaction with other patients and positive feedback from the group. A sense of interpersonal trust was also perceived to have been regained through patient group experiences. In addition, new skills or different behaviors, such as socializing and conversing without fear of shame or rejection, could be tested in contact with other patients.    A whole load of people, who understand you without you having to say a lot of words." (2.12 (24) "But also the feeling of being exposed to some patients whilst staying as an inpatient. " (2.1) "Yes, it was very exhausting never really being alone, never really being able to be just for myself. Then also the change to being an inpatient here; that was difficult. " (2.8) "Negative was that sometimes you could not cope with their problems. This sometimes was very stressful and I often took stories very much to heart. I then, sometimes, spent too much time on some people, and later thought, "Oh God, you shouldn't have done that, that was too much again! You've exceeded your own limits again." (2.19) 3. Social contacts outside of therapy (120)

D.4.2. Discharge from treatment (29) "So, I'm a total opponent of the day clinic, but at the moment I'm thinking it might have been the better option for me (patient laughs). It's easier to cut that umbilical cord. I mean, on the one hand I haven't felt as attached to the other patients as I did last time because you just don't spend as much time together. " (1.11) "For me, it was very difficult to leave the hospital on the whole. Also, because the other patients and the thought of how it all is being back. " (1.2) "And also, this sense of security you have being in the clinic stops at four o'clock….
It' s just not the same protected feeling, which one usually has for eight or ten weeks. That has made things easier. Simply keeping up your social contacts outside. " (1.11)

I.2.2. Sharing experiences (34)
Shielding them from feelings of sadness and loneliness, inpatients experienced particular relief through the possibility of intense contact with the other patients In addition, they also benefited from the mutual exchange of experiences and feedback within the patient group.

D.2.3. Group cohesion and sense of belonging (78)
Stressing the importance of a friendly group atmosphere for positive treatment outcome, day clinic patients reported a predominantly strong sense of belonging to the units' social environment. In regard to the inpatient community, some day clinic patients did not experience themselves as full members of the patient group, reporting feelings of greater distance and, in part, exclusion. These patients described difficulties in group integration and felt that the day clinic setting, in which patients are obliged to leave the unit by four o'clock in the afternoon, limited their possibilities of forming deeper relationships with other patients.

I.2.3. Group coherence and sense of belonging (93)
Inpatients in particularly reported a strong sense of emotional closeness and group coherence as well as a high degree of in-group identification. Many stated that undergoing therapy in the inpatient setting gave them a 'special status' and enjoyed being able to spend the evening with the other inpatients instead of having to return to feelings of loneliness at home. Inpatients emphasized their feeling of security within the inpatient group, while describing their relationship with day clinic patients as more distant. Especially the time spent together in the evenings after the daily therapy program had finished was seen as an integral part of inpatient therapy. For the patients, it served as an important basis for the development of a profound sense of belonging offering additional possibility for intensive discussions and the development of deeper relationships. (26) Feeling continually exposed to fellow patients concerns, some day clinic patients experienced interactions with the other patients as stressful.

D.2.4. Stress experience
Stating that the day clinical setting offered no possibility to retreat apart from the day clinic quiet room, patients described spending evenings at home as relieving as it helped them to distance themselves from other patients' concerns.

I.2.4. Stress experience (24)
Some inpatients experienced the constant exposure to their fellow patients and their moods as stressful. The frequent to constant interaction with fellow patients, sometimes resulting in conflict, was seen as a difficult and challenging part of therapy.

D.3.1. Support and improvement of social contacts/positive interactions with family and friends (31)
Providing them with additional 'external' aid during difficult times in therapy, many day-clinic patients experienced keeping in contact with family and friends during hospital treatment as supportive. Moreover, day-clinic patients felt that their interactions and contact with their partner or family improved throughout therapy as they were able to directly have to worry about some of the meals and your household. It just means the demands are different. In the clinic, they really do everything for you. One only has to think and go to therapy. " (1.11) employ skills learned during hospital treatment, such as improved communication skills, in the evenings at home.

I.3.1. Support and improvement of social contacts/positive interactions with family and friends (42)
Some inpatients reported to keep in adequate and good contact with family and friends during therapy and also felt to have improved relations with their social environment as a result of skills learned and insights gained in therapy. Particularly, patients, who reported to have good social resources, expressed their desire for more contact with their social environment. (18) Experiencing daily therapy as strenuous, some day clinic patients reported a need for rest in the evenings and to have reduced regular contact with their social environment in consequence. In addition, some patients stated that the continued confrontation with daily hassles and interpersonal conflicts at home was burdensome and, in their perception, impeded therapeutic efficacy. In particular, patients reporting conflicts at home expressed their desire for stronger shielding from their social environment through the hospital. (29) Particularly, inpatients with fragile social backgrounds experienced the hospital unit as a shielded, 'ideal world' providing them with a 'safe haven' far away from conflicts in their home environment. Especially the shielding from social contacts was described as beneficial during therapy as this was seen to enable inpatients to focus on their own difficulties undisturbed.

Treatment discharge and going back to everyday life (503)
D.4.1. Leaving the unit in the evening (9) Day clinic patients frequently stated difficulties with leaving the unit after the end of daily therapy. Some day clinic patients experienced the daily separation from the patient community and unit as exclusionary and reported to envy inpatients' continued contact.

I.4.1. Visiting home on the weekends (9)
Some inpatients reported difficulties during the weekends spent at home and stated their desire to stay in the unit. As main difficulties, most inpatients described to feel overwhelmed by their families' demands and lack of empathetic understanding. In particularly patients with poor social environments at home described feelings of loneliness and sadness to be most challenging over the weekends at home.

D.4.2. Discharge from treatment (29)
Day clinic patients reported that the daily return to their home and the con-tinued contact to their social environment enabled them a smooth transition from hospital therapy to everyday life. Feeling that they faced fewer difficulties in emotionally and physically parting with the unit compared to inpatients, the day clinic setting facilitated discharge form therapy in their perception. However, some day clinic patients described at discharge as challenging predominantly stating difficulties in leaving the 'safe haven' provided by the unit and losing the regular contact with therapeutic staff. (27) Discharge from the unit was experienced as abrupt by many inpatients. They perceived that the relief, which had been gained through the greater distance to stressors and conflicts at home as well as from the patient community, came to a sudden end. Furthermore, many inpatients felt overwhelmed and unable to cope with everyday hassles and social isolation at the end of therapy. Though some inpatients were able to part with little difficulty, especially patients reporting feelings of loneliness at home saw discharge as challenging. Here, having to leave the unit with the knowledge that others, still in treatment, would continue to be part of the patient community was experienced as highly burdensome.

D.4.3. Going back to everyday life (208)
Four weeks after discharge, many day clinic patients reported to have been able to successfully transfer their learning experiences from treatment to everyday life. In addition, an improved daily structure and an enhanced sense of well-being after therapy were described. However, some patients reported to have experienced a depressive relapse and difficulties in re-entering everyday life, such as maintaining a regular daily routine or transferring learning experience, after therapy due to continued conflict in the home environment and socio-economic constraints. In addition, some patients reported feelings of loneliness after discharge as the close relationships with the unit's other patients had ceased with the end of treatment. Here, previous social contacts and continued outpatient psychotherapy was experienced as supportive.

I.4.3. Going back to everyday life (221)
Some inpatients reported to have experienced little difficulty in going back to everyday life reporting significant symptom improvement, more self-confidence, improved daily structure, and good practicability of learning experiences. However, having experienced inpatient treatment as entirely detached from their life outside, the majority of inpatients felt that the transition from hospital to everyday life was difficult. Sometimes depressive symptoms, such as listlessness and fatigue, had reoccurred and difficulties in introducing and maintaining a daily structure, transfer-ring insights and learned skills in their home environment were described. Helping them to prepare for everyday life and to avoid loneliness after treatment, patients experienced an active confrontation with the limited duration of therapy in advance as well as prearranging meetings with friends and family as beneficial.

Day clinic-specific aspects. Experience of the daily commute and evenings at home (144)
D.5.1. Experience of the daily commute (40) Some day clinic patients described the daily commute between home and hospital as very stressful stating that the resulting exhaustion impeded their social activities. Especially patients reporting a severe lack of energy, fatigue symptoms, and concentration difficulties, or long-distance commutes, felt burdened. Despite improving as therapy progressed, some patients with comorbid social anxiety disorder or agoraphobia reported to have experienced the daily use of public transportation as highly stressful at start of therapy. Other patients valued the daily commute as a structuring element in their daily routine enabling them to prepare for or process treatment sessions.

D.5.2. Daily contact with the home environment (104)
Day clinic patients often experienced the daily contact with their home environment as relieving and reassuring. While many patients spent the hours in the evenings on social or leisure activities, some felt too exhausted to pursue activities after treatment. However, feeling distracted from therapy by their regular tasks and hassles at home, in particularly patients with conflicts at home experienced evenings at home as stressful. However, as family members often took on the majority of household chores during patients' treatment, only few described the daily confrontation with their life outside the clinic as burdensome. Especially patients living alone experienced difficulties in having to return to their empty homes and feelings of loneliness in the evenings. Some of these patients reported that the lack of social contacts at night resulted in a relapse to 'old' behavioral patterns (e.g. staying up too late).

Discussion
This study examined day clinic-and inpatients' views on their psychotherapeutic treatment in an integrated hospital setting, combining day clinic and inpatient treatment on one single unit. First of all, it is important to note that there were no outcome differences between the two examined groups regarding quantitative measures for depressive symptoms and improvement of interpersonal problems as previously published by Dinger and colleagues [24,25]. However, the current qualitative study revealed distinct differences within the RCT in regard to day clinic-and in-patients' perceptions of the start of therapy, integration in the patient community and skill transfer at the end of treatment. Although perceived as very demanding, day clinic patients appreciated the possibility to directly address interpersonal conflicts during evenings at home on the following day. In terms of offering time to prepare for and process treatment sessions, the daily commute was experienced as beneficial and the day clinic setting was perceived to facilitate a smooth transition back to everyday life following discharge. Despite positive experiences, day clinic patients were often ambivalent towards their treatment setting as they felt burdened by the demanding requirements of a day clinic treatment approach. Inpatients felt very much relieved by their treatment setting, and well integrated into the patient group. Start of therapy, particularly selfdisclosure during group therapy, was perceived as easy. Furthermore, inpatients were not only convinced of their treatment setting's effectiveness but also appeared to be sceptical towards day clinic treatment. However, despite inpatients' positive views of their own therapy setting, they struggled severely with the transfer to everyday life after discharge. In the following section, we will discuss the most prominent differential aspects of the two treatment settings in detail. All day clinic patients reported difficulties with initial integration into the existing patient group. In their experience, they had to be very proactive in order to feel as part of the patient group. Inpatients, in contrast, reported facilitated patient group integration due to the extensive amount of time spent with fellow inpatients during the evenings. In their experience, more time spent in the hospital led to greater trust and earlier self-disclosure both during group therapies and during informal discussions outside of therapy sessions. These findings contradict those of Eichler et al. [22], who reported that patients experienced inpatient and day clinic treatment as equally positive and effective. However, day clinic and inpatients were treated on separated units in their study and were not able to observe the other group directly. Furthermore, the standard psychiatric care in Eichler's study was less focused on psychotherapy and group processes.
The patient community was perceived as very supportive during further course of treatment across settings. Learning from other patients' experiences, having close social relationships again, and benefitting from other patients' feedback were listed as highly relevant aspect for the success of their treatment. Within their setting, inpatients developed a high sense of group cohesion due to "around-the-clock" therapy, but were reluctant in developing an intimate atmosphere with day clinic patients. Day clinic patients, in contrast, felt excluded and somewhat disadvantaged. The fact that day clinic patients were obliged to leave the hospital every day by 4 p.m. reinforced these exclusionary feelings. In regard to the findings on group cohesion, the integrated therapy setting, in which day clinic-and in-patients are treated together, is of specific importance. In the current study, the integrated setting was a major advantage for the scientific comparison of the two treatments as variables, such as therapy components and therapists, could be kept constant between conditions (high internal validity).
Although not in the focus of the current investigation, the integrated setting is also ideal for the investigation of changes of treatment intensity during therapy ("step up" and "step down"). However, in an integrated setting, the possibility of direct comparison with inpatients, who seemingly receive "more treatment, " appears to be a specific challenge for day-clinic patients. Based on previous research on the importance of group cohesion within a therapeutic community [23,36,37], our findings call for special attention to the day clinic patients' integration in the case of a mixed-setting therapeutic patient community. Therapeutic interventions in cross-setting subgroups might support and foster intergroup relations.
Day clinic patients perceived the daily commute as a further burden in addition to the demanding psychotherapy. In some cases, this extra strain impeded social and leisure activities or other positive resources at home due to exhaustion. It is likely that the daily commute is particularly challenging for depressive patients, as loss of energy represents one of the major diagnostic criteria [38]. In their non-randomized, observational INSTAP study, Zeeck et al. [9] found a significant negative relationship between loss of energy and clinical outcome for day clinic patients. Therefore, the question whether or not a significant loss of energy is a specific hindrance for day clinic therapy requires further attention. While Wietersheim et al. [13] reported that patients with anxiety disorders feel overburdened by the daily commute, some depressive day clinic patients with comorbid anxiety disorders in our study described a reduction of psychosocial fears when using public transport over the course of therapy. However, the careful evaluation of individual patient's abilities and setting demands remains imperative.
Regarding psychotherapeutic treatment itself, both patient groups reported that therapy was demanding but at the same time beneficial for reflecting feelings and behavior. Patients predominantly described positive relationships with the professional psychotherapeutic team, only some day clinic patients reported to have experienced a more distant relationship. Inpatients reported that being sheltered from their social environment represented a key factor to and basis of their therapy success. However, the underlying explanatory models for this experience differed within the inpatient group. Some inpatients highlighted their desire to gain distance from severe conflicts at home, while others emphasized their wish for a trouble-free 'safe haven' . The latter often struggled with feeling of loneliness after discharge. In contrast, day clinic patients experienced contact with their social environment far more positively, especially when there were no major conflicts at home. In these cases, they described their partners, relatives or friends as a source of support. In cases of conflicts within their social environment, day clinic patients tended to perceive themselves as overburdened. Accordingly, the level of social conflicts should be taken into account, when evaluating the differential indication for day clinic-versus in-patient treatment settings.
Focusing on the end of therapy and skill and insight transfer to everyday life, both patient groups reported that they experienced difficulties when leaving the sheltering therapy unit. However, this challenge was perceived differently in both groups. Day clinic patients emphasized the experience of loss and sadness when having to leave the safe haven of the hospital and their attachment figures during therapy, while inpatients reported greater concerns in regard to having to abruptly face their everyday life again. The sheltered setting of inpatient treatment appears to promote the desire to be taken care of (pronounced dependency) which is also reflected in the frequent wish to remain in the trouble-free unit during weekends. On the other hand, the intensive support during the limited treatment time may promote the internalization of positive relationship experiences, especially for patients with increased self-reliance. In successful inpatient therapies, these positive relationship experiences appear to strengthen patients' self-view and allow a more confident re-entry into their everyday life. Day clinic patients, by contrast, 'practice' and experience parting from the patient group every day during treatment. Wietersheim et al. [13] assumes that day clinic treatment counteracts tendencies for pronounced dependency and regression, which might ease re-entry into everyday life. Furthermore, day clinic patients quickly learn that therapists are not able to provide all-embracing care, having to resume responsibility for their own life at an early treatment stage in consequence [39]. Some day clinic patients, however, were envious of other patients who were still allowed to stay in the hospital, while they were back at home. Inpatients who relapsed during the 4-week followup experienced the e stark change from the hospital to everyday life as triggering. Accordingly, previous authors have proposed a 'step-down-approach' with inpatient care being followed by day clinic treatment to facilitate a smoother transition for inpatients [9]. When focusing on the transfer of therapeutic insights and skills to everyday life, day clinic patients highlighted that transfer was eased by the possibility of discussing interpersonal conflicts at home during therapy the next day. This supports previous findings by Zeeck et al. [14]. Von Wietersheim et al. [13] showing that the recurrent "escape" from the home environment to the sheltered hospital was perceived as a major benefit of the day clinic setting. In a previous qualitative study using semi-structured interviews, the successful transfer of insights and skills from therapy to everyday life was shown to be a crucial factors for day clinic patients [8]. Furthermore, both groups experienced a prescheduled appointment with the subsequent outpatient therapist as a further beneficial and securityenhancing factor after discharge.

Limitations
Some limitations of our study should be noted. Firstly, potentially biasing our analysis, our study is limited by the small number of participants due to its qualitative approach. However, the risk of bias is reduced by the fact that all patients, who completed the randomizedcontrolled trial by Dinger and colleagues [24,25], participated in the interviews. Alsoto participate , since only 44 out of 140 eligible patient participants decided in the randomized clinical trial, it has to be noted that the current sample represents a selected group of participants. This limits the generalizability of our findings. Secondly, our results are limited to integrated settings, in which day clinic-and in-patients are treated together. However, suggesting that some of the observed effects may be specific to integrated settings, previous evaluations of separated day clinic-and in-patient treatment units have shown mixed results reporting either no differences between settings, or a patient preference for day clinic treatment [22,[40][41][42] Lastly, although the qualitative content analysis was performed according to principles of inductive category development and was verified by a second researcher, the examination can be considered to be less generalizable than quantitative approaches due to the subjective nature of qualitative studies. However, with the aim of drawing a more complete picture of this multilayered topic potentially identifying new research aspects, this methodological approach was specifically chosen to elucidate day clinic-and in-patients' perceptions of treatment settings.

Conclusions
In line with previous research, this study provides further indication that depressed patients perceive the day clinic treatment's main advantage in the possibility to address current conflicts, while simultaneously being able to test proposed solutions in the home environment. However, in our integrated setting, day clinic patients reported difficulties in patient group integration and development of group cohesion. Inpatients saw their main advantage in the sheltered setting, distance from their social environment and maximum patient group support. However, results also show that inpatients with pronounced dependency and low interest in keeping in contact with their social environment experienced more difficulties going back to everyday life and increased depressive symptoms after discharge. For depressed patients, the clinical indication for day clinic therapy requires a careful consideration of potential difficulties. Our study identified overburden by the daily commute, the continuous stay in a potentially dysfunctional environment and interpersonal problems as risk factors for a successful patient integration. Hence, integrated models providing the possibility of a flexible step-up as well as step-down approach may be especially beneficial for personalized treatment planning in intensive settings [13]. At the same time, further research on day clinic-and in-patient treatment could benefit from our study's results with particular focus on the transition from hospital treatment to everyday life.

Abbreviations
RCTs: randomized controlled trials; MDE: major depressive episode; TA: thematic analysis; DSM: diagnostic and statistical manual for mental disorders.

Authors' contributions
CN and UD conceived the study. DH, MH, JH, JCE, WH, HS, and UD participated in the design of the study. MH conducted the semi-standardized interviews. CN and JH carried out the qualitative analysis. CN, JH and UD finally drafted the manuscript. All authors read and approved the final manuscript.