Online programs to strengthen the mental health of medical students: A systematic review of the literature

ABSTRACT Medical students have been shown to be vulnerable to mental stress. Strengthening individual protective characteristics can be one cornerstone for promoting medical students’ mental health and thereby preventing mental disorders. Online programs are an opportunity to provide appropriate options that have the advantage of being accessible from anywhere, at any time, and with a low entry threshold. This review provides a literature overview of current online programs for medical students. The findings can serve as a point of reference for designing effective online programs for mental health-promotion and mental disorder-prevention in medical curricula. We applied a systematic literature search in PubMed, ERIC, Cochrane, and Web of Science. Programs offered had to be web-based, and the addressed group had to be medical students. Protective individual characteristics for mental health and information on the programs’ effectiveness were included in the search. As outcomes, we included mental health, burnout, symptoms of depression, anxiety, and well-being. The search yielded 723 articles; of them, 11 met the inclusion criteria. Programs found were grouped according to their focus: mental health literacy, mindfulness, based on Cognitive Behavioral Therapy, or peer support. Two studies showed significant reductions in perceived stress; one study indicated reduced burnout levels. One program had significant immediate effects on mindfulness, empathy, and resilience; two studies indicated strengthening coping strategies. Two programs were qualitatively assessed as helpful; two studies are ongoing. Nine studies lacked control groups; two randomized controlled trials were ongoing. Only a few online programs with limited evidence of effectiveness were found. They addressed protective individual characteristics, highlighting their importance for mental health. Thus, more health-promoting and mental disorder-preventing programs with high-quality effectiveness studies are necessary. An integration of such programs into curricula would allow for greater utilization and could give greater emphasis to and prioritize mental health in medical education.


Introduction
University education is a special and challenging period of life that, while offering many new experiences, can be associated with stress and psychological strain [1,2]. University students worldwide experience a decrease in well-being and an increase in mental morbidity [3,4]. The reasons described are unfamiliarity as well as new situations [5], theses, exams, and high demands on oneself [6]. The World Health Organization (WHO) has addressed this issue through the WHO World Mental Health International College Student (WMH-ICS) initiative [4,7]. The goal of this initiative was to obtain longitudinal information about the prevalence and impact of mental health disorders among university students worldwide, as well as to lay the groundwork for the implementation of preventive interventions [2]. Results showed that 20.3% of university students were affected by mental disorders such as major depression [4,8], which lead to problems with home management, college-related work, close relationships, and social life [2]. Moreover, the study identified a low utilization of related treatments [4,8] among a large proportion of university students.

Trends in mental health among medical students
Although not separately analyzed in the representative WMH-ICS study, there is a robust body of studies that identified medical students, in particular, as vulnerable to worrying mental health developments [9][10][11][12][13][14][15]. In a meta-analysis of 167 cross-sectional studies (N = 116,628) and 16 longitudinal studies from 43 countries, Rotenstein et al. reported an estimated overall prevalence of depressive symptoms of 27.2% (range: 9.3%-55.9%) [13,14]. Moreover, medical students show significantly higher rates of anxiety symptoms compared to the general population [15], and report fatigue, nervousness, uneasiness, lack of sleep, and feeling tired all the time [15]. Described reasons especially for medical students, are the amount of learning materials, perfectionism tendencies, and, in clinical phases, death and critically ill patients [10,14].
In accordance with the described trends, medical students should be preventively assisted in maintaining their mental health as early as possible to prevent the development of mental disorders [16]. Reforms in medical education have reacted to these findings and claim a stronger focus on conceptualizing curricula considering mental health [17]. As it is required that students should be seen as individuals within their educational context [17], curricular as well as individual interventions play a significant role in the conceptualization of curricula that consider students' mental health. Curricular interventions subsume, for example, changes to course content [17,18], reduction of workloads, or straightened timetables. Individual interventions focus on individual characteristics [18,19] and can be thought of as the promotion of mental health, prevention of mental disorders, or treatment of mental disorders [20]. Promotion aims to strengthen positive aspects of mental healthsuch as characteristics that have been shown in the literature to be protective of mental health [20]; prevention aims to reduce the likelihood of developing mental disorders in the general population or in individuals who are identified as being at risk of a future disorder, and treatment is provided to people with diagnosed mental disorders [20]. Slavin [14] stated that promotion and prevention over treatment is a key point in improving medical students' mental health.

Relevance of online programs to promote mental health and prevent mental disorders
The described low uptake of personal consultation for mental health support by medical students [14,21] may be explained by fears of stigmatization, shame, barriers to time and place, and distrust of support offers [1,9,[22][23][24][25][26]. New technologies have facilitated online mental health support that may overcome some of these barriers as they can be accessed anonymously from anywhere and at any time and can be used individually in a safe or well-known setting [1,9,[27][28][29]. Therefore, online programs can be a cornerstone in creating medical studies that support students' mental health.
In our overall project aim to design an online program to promote medical students' mental health and thereby prevent the development of mental disorders, we identified a lack of overview on existing programs that are specifically designed for medical students. To address this research gap, we conducted a systematic search of the literature. We aimed to identify existing online programs designed for medical students' mental health promotion and mental disorder prevention to give an overview on protective characteristics they address as well as the measures employed to assess their effectiveness. This systematic review of the literature can serve as an orientation for medical schools in conceptualizing low-threshold online services for mental health promotion and prevention.
As mental health promotion and individual prevention can be implemented by strengthening protective individual characteristics [20], we now focus on these characteristics.

Protective individual characteristics
To define our search term, we screened the evidence on individual characteristics that were identified to be protective for mental health as they promote wellbeing and/or reduce the risk of mental disorders. Therefore, their addressing in online programs can be considered relevant:

Self-efficacy
Self-efficacy is the conviction that one can influence and overcome challenges and difficult situations through one's own strength and actions [30]. Selfefficacy has been shown to be predictive of feelings of stress in medical situations characterized by uncertainty [31] and to be trainable in health professional education [32].

Resilience
Resilience describes a person's ability to respond flexibly and appropriately to demands in changing situations and to cope with or recover from difficult or stressful situations without suffering any consequential psychological damage [33]. Like selfefficacy, resilience has been shown to be a modifiable construct [34,35].

Empathy
Empathy describes a person's ability to recognize and feel the feelings of others [36,37]. Lack of empathy has been shown to negatively correlate with wellbeing [37,38] and positively correlate with the development of burnout [39][40][41][42]. A recent German study involving medical students indicated that empathy can be strengthened through empathy training with standardized patients [43]. These findings suggest

Coping and self-regulation strategies
Strategies that a person uses to cope with stressful situations and experiences are generally summarized under the term 'coping strategies' [44]. Different coping strategies are used by medical students and physicians, as shown by Lemaire and Wallace [45]. Some of these strategies (e.g., self-regulation strategies) correlate negatively with emotional exhaustion as a symptom of burnout and have been shown to help in coping with challenging situations in the medical profession [45]. Various aspects of selfregulation, which are frequently distinguished and mentioned as relevant subfacets [46], such as cognitive and metacognitive self-regulation, academic selfcontrol, motivation, and emotional regulation, correlate negatively with the development of burnout [47,48].

Mindfulness
Mindfulness is defined as the quality of awareness that occurs when intentionally focusing on experiencing the present moment in an accepting and nonjudgmental manner [49]. It has become an increasingly prominent psychological construct addressed in interventions worldwide [50].
Mindfulness-based interventions have been shown to reduce depression among medical and premedical students [51].

Self-compassion
Self-compassion entails self-kindness, a sense of common humanity, and a balanced, mindful relationship with unpleasant thoughts and emotions [52][53][54]. Selfcompassion has been shown to be associated with fewer depressive symptoms and burnout [53,55,56].

Materials and methods
We conducted a systematic review of the literature using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist as a guide [57].

Information sources
We assessed the PubMed, Cochrane, Web of Science, and ERIC databases. The search terms had to be included either in the title or abstract (PubMed and ERIC) or in the title, abstract, or as a keyword (Cochrane, and Web of Science), as these served as the basis for screening the findings.

Search strategy
Based on the first peer review of this article, we extended the search string and conducted the final search post review in January 2022. The search term definition was guided by the following premises: (1) The target group had to be medical students. Various denominations were included. (2) As we focused on online programs, the search strings had to include the word 'online' and suitable alternatives. (3) Studies had to be about an intervention or program with a preventive character. (4) The promotion of mental health and wellbeing and the prevention of depression, burnout, or anxiety had to be the aim of the online program. (5) The online program had to address at least one of the described protective individual characteristics. In the search term, premises 1-5 were connected by an AND; alternatives in wording and spelling were connected within each premise by an OR: ((medical students OR students of medicine OR medicine students OR medical education) AND (online OR web-based OR webbased OR web based OR internet-based OR internetbased OR internet based OR digital OR telehealth OR telemedicine) AND (intervention OR prevention OR training OR programme OR program OR offering OR offer) AND (mental health OR depression OR depressive symptoms OR depressivity OR burn-out OR burnout OR burn out OR well-being OR wellbeing OR anxiety) AND (self-efficacy OR selfefficacy OR self efficacy OR resilience OR empathy OR coping strategies OR selfregulation OR selfregulation OR self regulation OR mindfulness OR self-compassion OR selfcompassion OR self compassion)) We considered articles starting in 2000 given the study topic of online, web-based, or digital programs.

Selection and data collection process
Duplicated papers were excluded. Studies were screened for inclusion in the following way: One reviewer went over all the abstracts to remove the articles that certainly did not meet the inclusion criteria in accordance with premises 1-5.
The full text of all the remaining articles was reviewed independently by two reviewers. The results were discussed and discrepancies investigated until a consensus was reached. The remaining articles that formed the corpus for the results were subjected to the synthesis method. If the full text of an article could not be accessed, the article's authors were contacted directly.

Eligibility criteria
Articles were included if they fulfilled the following eligibility criteria: (1) The study reports an empirical study; (2) The study was conducted in one or more universities; (3) The article provided any information on an accompanying research procedure that investigated the impact or effects of the intervention or program (both quantitative and qualitative assessments were accepted); and (4) The article was published in an English-or German-language scientific journal.

Study quality and risk of bias assessment
To estimate the risk of bias, each study's methodological quality was assessed based on the criteria established by Jadad et al. [58]. It is important to state here that, despite the possible risk of bias of the included studies being discussed by the two reviewers, a possible risk of bias in one study did not form a criterion for this study to be excluded from our review.

Synthesis method
We inductively identified categories to (1) group the identified online programs in accordance with their overall approach. (2) Within these, we sorted the studies by their provided evidence in the following order: Randomized controlled trials (RCTs) were presented above studies without a control group. Studies with a higher number of participants were presented above studies with a lower number of participants. Significant results were presented above results without significance. If there were two studies on the same or nearly the same intervention, they were reported chronologically.

Selected studies
As illustrated in Figure 1, 723 records were found in the four databases using the search string described above. In accordance with this selection procedure, 70 studies were retrieved for detailed examination, which resulted in 11 articles that were ultimately included in the systematic review.

Study characteristics
Five studies were conducted in the USA. One study was conducted in each of the following countries: Canada, Finland, Spain, Chile, Australia, and Iran. There were two cases in which the same group of authors conducted two studies in each case. Two studies were explicitly named RCTs, whereas most studies were conducted with a pre-posttest design without a control group.

Study outcomes
For the 11 studies (see Table 1), we identified four approaches that serve as the logic for the presentation of the results: mental health literacy, mindfulness/ meditation, based on internet-based Cognitive-Behavioral Therapy, and peer support.

Mental health literacy
We found one study on a mental health literacy (MHL) intervention that was implemented in 2020 during the COVID-19 pandemic at the University of Turku, Finland. MHL is a component of health literacy that aims to increase knowledge about mental health and positive attitudes toward available mental health services [59,60]. Insufficient MHL may result in increased stigma, lack of recognition of mental health problems, and barriers to help seeking, which is associated with increased stress [60]. Therefore, the aim of this intervention was to reduce stress and thereby enhance well-being by increasing mental health awareness and reducing the stigma associated with mental health problems. This intervention was called Transition program and based on the Canadian Transitions program, which is a program in the form of a booklet (available in hard copy, ebook, and mobile app formats [61]) that combines MHL with comprehensive life-skills resources to support students in their transition to university. The program here was offered completely digitally and consisted of two lectures and self-learning digital materials that focus on three themes. Theme 1 comprised skills for independent life, study skills, and relationships. Theme 2 addressed stress management skills and strategies to sustain mental health. In theme 3, users were provided with information about the variety of mental disorders, treatment, and help seeking [60]. Additionally, the Transition program included a mindfulness component with a series of audio tapes on the theory and exercises to learn about mindfulness as a stress-reduction strategy. As mindfulness was not the focus, we grouped the Transition program distinctly from approach 2. The students' mental health knowledge, their attitudes toward help-seeking, and their emotional wellbeing improved significantly after the program, and they showed significantly reduced stress levels.
Changes concerning mental health knowledge and emotional well-being remained at follow-up, whereas changes in stress levels and help-seeking attitudes were not maintained two months after the program.

Mindfulness/meditation
The only two RCT studies found in this systematic review are still ongoing. The documents found are registered study protocols. One registered (August 2021) mindfulness intervention was offered at the University Diego Portales in Santiago de Chile during the COVID-19 pandemic [62]. The aim of the study is to evaluate the effectiveness of a brief online mindfulness, compassion, and intercare-based intervention to prevent adverse impacts of the pandemic on the mental health of medical students. For that purpose, the protocol reported an RCT in which 360 participants were randomly assigned to 1) a mindfulness, compassion, and intercare-based intervention, 2) a psychoeducational intervention, or 3) a waiting control group. The mindfulness intervention consisted of mindfulness-based cognitive training and teaching techniques for practicing at home. The psychoeducational intervention included psychoeducation about stress, anxiety, self-care, and effective communication. In addition, it was reported that all participants were offered psychological counseling if they showed a high score on depression or anxiety symptoms. All participants had academic breaks of two weeks per semester and flexibility in submitting work, attending practical activities, and taking exams [62]. The results have not been published yet.
A second RCT registration protocol (December 2020) called Compassion Cultivation Training (CTT) was conducted at Stanford University, USA. An 8-week mediation program was offered as an online version with weekly online sessions, supplemented with daily exercises led by a certified instructor to support medical students' mental health during the COVID-19 pandemic. The objective was to determine the effectiveness of this training on self-compassion, empathy, resilience, mindfulness, and emotional regulation, as well as on depression, anxiety, stress, and burnout [63]. N = 40 medical students are currently enrolled. Again, no results have yet been published.
Two articles by Kemper et al. reported on a program for healthcare professionals in general, including medical students, doctors, nurses, and social workers [64,65] at the Ohio State University College of Medicine. The online mind-body skills program (MBS) comprised 12 1-h modules that were divided into four general topics: focused attention meditation (relaxation response), mindfulness meditation, positive affect meditation, and guided imagery/hypnosis [64,65]. The acute effects of this program on mindfulness, stress, empathy, and resilience in 513 participants were investigated. No control group was reported. The participants had to complete at least one module of the program and were free to choose the module(s) they wanted to work on. Through self-assessment scales, significant improvements in mindfulness, empathy, and resilience, as well as significantly lower levels of perceived stress, were noted [64]. Self-assessment scales were used again in the second study. 12 weeks after the MBS (103 participants who completed all modules of the training), significant effects could be shown for perceived stress, mindfulness, and selfcompassion, but not for empathy and resilience [65].
A pilot study by Moore et al. conducted at the Australian Rural Clinical School reported on the effects of an 8-week mindfulness program for medical students on self-compassion and stress [66]. The program included short online lectures on mindfulness, guided mindfulness meditation sessions, and videoconference sessions for support and motivation. Lectures included topics such as stress reduction and performance, reducing distraction and procrastination, and mindful use of technology. Mindfulness sessions included, for example, techniques such as body scans, mindful breathing, and mindful listening. Moore et al. conducted a singlearm prospective mixed-method cohort study that included 47 medical students and no control group. Half of the participants used the program at least once a week. At the follow-up survey 4 months after program completion, the researchers found a significant increase in the students' self-compassion and a significant reduction in perceived stress.
Danilewitz et al. developed and evaluated a webbased mindfulness program called MIND-MED to increase empathy, mindfulness, and self-compassion and to reduce burnout in medical students at the University of Ottawa, Canada [67]. MIND-MED consists of seven sequential online modules that are accessible to students for purely self-administered use over one semester. It suggests techniques such as body scans, meditations, mindful eating exercises, and yoga. Additionally, it provides tips for promoting mindfulness in everyday activities. Furthermore, relevant reading material about mindfulness and student well-being, as well as links to other websites that contained information about mindfulness, were provided. The researchers offered MIND-MED as a voluntary additional program in a prospective pilot to 45 medical students without a control group. The program had high acceptance but no significant effects on empathy and burnout. Some students stated that they did not find enough time or were too stressed to regularly perform the meditation exercises [67].

Based on internet-based cognitive-behavioral therapy
Lattie et al. [68] developed ThinkFeelDo, a 6-week online program based on internet-based Cognitive-Behavioral Therapy consisting of online lessons and interactive online tools to promote cognitive and behavioral coping strategies and to reduce stress and burnout among first-year medical students. Through 10-minute online lessons, participants from the University of Illinois at Chicago learned about the topics of behavioral activation, cognitive restructuring, and dealing with anxiety by using text and videos [68]. In addition, an associated website offers interactive tools, such as activity monitoring, mood tracking, documentation of cognitive restructuring and goal setting, and a relaxation exercise to implement the content learned in the lessons [68]. After the completion of ThinkFeelDo, participants showed high acceptance and usability scores, and an increase in cognitive and behavioral coping strategies as well as a decrease in burnout were measured in the pilot study [68].
Two years later, the authors investigated the effect of a slightly modified version of ThinkFeelDo on the well-being, stress, depressive symptoms, anxiety disorders, and coping strategies of first-year medical students [69]. This time, the program ran for 16 weeks. There were slight improvements in the medical students' coping strategies, but no significant pre-post differences in depression and anxiety symptoms, which were initially low, were observed. ThinkFeelDo was rarely used repeatedly, although students reported having a high interest in it [69]. In both studies, the authors reported no control group.

Peer support
George et al. [70] used Facebook to establish online support for first-year medical students during the initial 11 weeks at the Pennsylvania State Hershey College of Medicine. They created a Facebook stress management group that provided peer support based on a blend of CBT and Lazarus & Folkman's model of stress and coping [71]. Every day, new content was posted that provided personal video narratives from older medical students, educational information, study tips, and stress management resources, such as problem-focused coping strategies (e.g., changing the environment by reframing or relaxing). In total, 95 medical students used the service and reported better stress management and coping strategies through open self-report items. No control group was included [70].
Kazerooni et al. reported on an offer at the Shiraz University of Medical Sciences, Iran, which was developed last year during the COVID-19 pandemic [72]. A social media platform was created for crosssemester peer exchange to reduce stress, anxiety, and psychological strain and to support the development of strategies to cope with this unfamiliar pandemic situation. It involved senior medical students assisting junior medical students in coping with anxiety and stress brought about by the COVID-19 pandemic. In total, 371 junior students tested the platform as mentees, sharing psychological difficulties, worries, and fears, and 10 senior students acted as coaches [72]. In their role as coaches, they recommended stress management and relaxation techniques, engagement in exercise, maintenance of online contact with family and friends, and time management during quarantine; moreover, they were generally available as contact persons. The majority (71%) of the junior students found peer support helpful in adapting to unfamiliar and stressful situations, and that it was a unique experience beneficial for their professional growth [72]. Concrete measures of stress, anxiety, or other constructs, as well as coping strategies, were not reported, nor was a control group installed. Because of the COVID-19 pandemic, the initial intervention was conducted virtually via the social media platform for about one year; however, it has since continued in hybrid form and is now both

Discussion
With this systematic review of the literature, we aimed to identify online programs developed for mental health promotion and mental disorder prevention in medical students. Applying a systematic search, we identified 11 studies on nine different online programs -two programs were evaluated in two consecutive studies -which addressed medical students' mental health. The studies included one MHL intervention [60], an internet-based program based on CBT [68,69], MBS training [64,65] as well as further meditation and mindfulness programs [62,63,66,67]. Two programs used the supportive effects of peer support [70,72]. Didactical formats differed and included online lectures, guided lessons, or sessions with practice exercises, interactive tools, and online peer-to-peer communication via social media platforms.
Overall, the accompanying studies on the effects or effectiveness of each program were methodologically of rather low quality and significance, but the reported results of their overall good acceptance suggest that such programs are quite well received by their users. The only two RCTs we found are still ongoing. The small number of programs found also indicates that, to date, there are few online programs especially designed for medical students.
The programs found addressed protective individual characteristics such as empathy, resilience, mindfulness, self-compassion, or coping strategies, and focused on outcomes such as perceived stress, depressive symptoms, or burnout.
Based on our systematic review of the literature, we derive the following implications: (1) Digital support seems to attract interest The predominantly good acceptance of online programs indicates that medical students are interested in digital support to maintain or strengthen their mental health. In the current pandemic, the advantages of online programs, such as the possibility of using them independently of time and place, are particularly apparent.
(2) Definition of targeted learners None of the included studies reported a specific needs assessment of the target population (i.e., medical students) before developing the program. With a longitudinal questionnaire monitoring mental health development during medical school, both stress hot spots and students in need can be identified [73]. In this way, a student-oriented, needsbased online program can be developed as a component of a curriculum that considers mental health. (

3) Need for effectiveness measures
Effectiveness measures were reported in most studies, but the samples were partly small and lacked a control group. Most included studies mentioned the need for further methodologically high-quality studies to verify the effectiveness of their measures [66][67][68]72].
In agreement with them, we also emphasize the need for high-quality studies on this topic to achieve more reliable and valid statements on its (differential) effectiveness-that is, to determine which individuals may particularly benefit from online programs and how to adapt the content of the program, if necessary.
(4) Mindfulness training and peer support showed a positive impact Although the results of some of the studies need to be interpreted cautiously, they are nevertheless an initial indication of the positive impact of the approaches and content offered in the online programs on mental health. They indicated that short online sessions on relaxation and meditation and mindfulness training in general can strengthen protective characteristics, such as resilience and empathy, and therefore promote well-being as well as prevent the development of depression and burnout symptoms. Peer support was well accepted and considered helpful in adapting to stressful situations. As these two components had positive effects, future online programs should combine short online sessions on mindfulness training with peer support. Peer-to-peer communication should also be fostered to promote the exchange of experience and facilitate mutual support.
(5) Online programs should be an integrated component The identified programs were offered to medical students as additional services which-as found in the study by Lattie et al. [69]-can risk continuous use because of time constraints or perception as additional effort.
These findings indicate a need for more programs that are wisely implemented into the curriculum as an integrated component. In this way, an add-on character and additional workload can be reduced, thereby achieving a sustainable combination of individual and structural interventions to promote mental health and prevent mental disorders in future physicians-in accordance with Slavin's [17] understanding of students as individuals within their educational context. This finding could be useful to curriculum developers who plan medical students' education within a curriculum that considers mental health: effective mental health promotion as well as effective prevention of mental disorders consist of both individual and structural interventions. This requires individual interventions to be embedded into a structurally (e.g., in terms of time schedule) adapted curriculum, as they are only one component in an entire setting; this means that structural changes in the curriculum itself, such as changes in scheduling or course content, are necessary.

(6) Dissemination of our findings
We sought programs specifically designed for medical students. Nevertheless, the findings of our review can be disseminated to other student groups as well as even other institutions in general, as the need for support to keep students and other community members (for example faculty, residents, and practitioners across health professions) mentally healthy is universal [16]. Tailored (i.e., developed on the basis of the needs of the respective target group) online programs as individual interventions that are structurally embedded into a curriculum can be a good way to promote mental health of other community members and in other institutions as well.

Limitations
This review has some limitations. The only two RCT studies are registered protocols only; so far, they are without published results. Since all studies described the experience of only one institution, the generalizability of each of the findings is limited. We inductively grouped the results into four approaches that appeared reasonable and most prominent based on the focus of the respective program. Nevertheless, the mental health literacy approach by Kurki et al. [60], included a mindfulness component with mindfulness elements as well. The potential effects of such additional components should be taken into account when interpreting the effectiveness of a program.
The approach based on internet-based Cognitive Behavioral Therapy is actually represented by only one intervention, which was studied twice -each time in a slightly modified form. Two studies grouped under mindfulness/meditation were conducted on the same intervention by the same group of authors, as reported. Thus, the sheer number of studies on these two approaches is not the same as the number of different interventions or programs.
Our review includes articles published in international journals and two registered trial protocols. Relevant literature may have been excluded, for example, from conference papers, conference proceedings, or theses, as well as in languages other than English or German.
Although the search string has been adjusted, there might be other individual protective characteristics that we did not include in our search but that might be relevant for mental health. Thus, some relevant online programs for medical students may have been overlooked.

Conclusion
From this systematic review of the literature, which provides an initial overview of online programs to strengthen medical students' mental health, we derive the following conclusions for mental health promotion and mental disorder-preventing programs in the university setting or, to go even further, in other institutions in general: (1) Online programs seem to be a good way to support individual mental health promotion and prevention by strengthening protective characteristics, also for target groups other than medical students. (2) To better understand the respective target groups and their needs, we suggest a precise needs assessment among them as a basis on which online programs are designed to ensure their necessity as well as their best possible fit. (3) Online programs would benefit from curricular integration. There is a need for a curricular -or more general -structural integration of such tailored online programs or interventions, for example by giving them a fixed and obligatory slot in the timetable so that students or other addressees have enough time and space to use and benefit from them. This again underlines the fact that individual and structural prevention should not be separated from each other but should be considered interacting components. (4) Effectiveness studies can help to further understand the contribution of online programs to mental health-promoting as well as mental disorder-preventing curricula.