#Stayhealthy - Monitoring and Maintenance of Mental Health Under Conditions of Social Isolation During the Corona Crisis

The COVID-19 pandemic has led to a global health crisis with, so far, over 21 million registered cases and more than 700.000 deaths worldwide. In order to slow down the rate of new infections, millions of people have been directed to stay at home, thereby accepting severe restrictions of social contact and personal freedom to move. With fear of infection and economical loss as additional burdens, the current conditions have led to a significant increase in psychological distress and risk for the onset of mental disorders among the general population. Empirical evidence on effective measures to support mental health in COVID-19 "homestayers" is lacking.

In the present study, the investigators therefore used a randomized controlled trial (RCT) design to investigate the effects of two online intervention programs derived either from the field of positive psychology (PP) or acceptance and commitment therapy (ACT) with a third group of participants writing an online diary only (control group). Furthermore, over the entire study period, individual daily coping strategies were collected. A total of 138 adult German "homestayers" participated in the RCT with two weeks of daily interventions during the first "lock-down" period in Germany (April 19th to May 3rd 2020). Measures of stress, mental health (depression, anxiety) and subjective well-being (subjective vitality, overall well-being) were collected at baseline, at the end of the two-week intervention period and another 14 days after that (follow-up).

A total of 138 individuals - recruited via university-wide emails and social media - completed the baseline questionnaire and agreed to participate in the study. Inclusion criteria were an age between 18 and 70 years, knowledge of the German language as well as conditions of increased social isolation at the beginning of the study. The latter criterion was operationalized by only including individuals who were currently staying mostly at home due to the Corona crisis (home office; quarantine measures; stay-at-home orders) with no (or only very few) direct contacts outside of their own household. The only relevant exclusion criterion was an acute diagnosis (within the last 3 months) of a mental disorder by a medical professional.

Procedure: A link in the invitation email of the study led to the online platform SoSciSurvey, where participants received information about the study, standards of data security, gave informed consent to participate and filled out pre-measures (t1). Upon completion, all participants who met the inclusion criteria were randomly assigned to one of three groups (ACT, PP, control group) and received their personal login credentials to the online platform \[Synergetic Navigation System, SNS: ccsys.de, Version 3.7.54; 36, 37-39\], which was used to administer daily questionnaires and intervention programs. In order to keep the changing societal situation constant for all participants, the study protocol started on April 19th 2020 for all three groups. For a period of 14 days, the two intervention groups received a daily prompt (at 6 AM) via email that their "exercise of the day" was accessible in the SNS. In order to read the exercise instructions, participants had to log into their account via app or web browser. Every day, a new exercise appeared in the system. The intervention period with daily email prompts ended after 14 days.

In the evening (at 5.30 PM), all three groups received an email notification to fill in their daily review questionnaire ("online diary"), every day over the entire study period of 28 days. On day 14, all participants received an email notification to fill in the post measures (t2) available in their SNS account. On day 28, all participants received a notification to fill in the follow-up measures (t3).

Questionnaires and testing material:

At t1 (baseline assessment) participants were asked for information regarding general demographics, their personal living situation, social situation and current status of health. Moreover, participants were asked to indicate the influence of the Corona crisis on their personal lives as well as the adequacy of political measures taken to meet the Corona crisis on visual analogue scales (1 = not at all - 100 = very much).

The following outcome measures were assessed to evaluate the impact of the time spent in relative isolation under conditions of increased stress due to the Corona crisis and potential buffering effects of the interventions: General stress level was assessed using the German version of the stress module of the patient health questionnaire (PHQ-D); as a measure of depression, we used the nine items of the depression module of the patient health questionnaire (PHQ-9); anxiety over the last two weeks was assessed using the 10-item German short version of the State-Trait-Anxiety Inventory (trait version, referenced to the last two weeks); additionally, five items measuring participants' general subjective vitality were included to measure the influence of social distancing on a dynamic feeling of energy and psychosomatic well-being; overall well-being was assessed using five items of the World Health Organization Well-being Index (WHO-5).

"Online diary" and assessment of coping strategies: All participants received a daily review questionnaire which contained two open questions instructing participants to write down 1) relevant events during the day, and 2) things that had helped them in coping positively with the current situation. Participants from the intervention groups were also asked to indicate whether they had carried out the intervention that day (yes/no).

Interventions: see Interventions section

Eligibility Criteria:
Inclusion Criteria:

* knowledge of the German language
* conditions of increased social isolation at the beginning of the study (only individuals were included who were currently staying mostly at home due to the Corona crisis \[home office; quarantine measures; stay-at-home orders\] with no \[or only very few\] direct contacts outside of their own household)

Exclusion Criteria:

* acute diagnosis (within the last 3 months) of a mental disorder by a medical professional