Janzarik 2022.

Study characteristics
Methods	Study design: randomised controlled trial Study grouping: parallel group
Participants	Baseline characteristics Intervention (resilience) Age (mean ± SD): 47.4 ± 10.8 Sex (N (% female)): 35 (92%) Sample size: 38 Years of experience (mean ± SD): NR Control (no intervention) Age (mean ± SD): 46.5 ± 10.4 Sex (N (% female)): 31 (91%) Sample size: 34 Years of experience (mean ± SD): NR Overall Age (mean ± SD): NR Sex (N (% female)): NR Sample size: 72 Years of experience (mean ± SD): NR Included criteria: NR Excluded criteria: NR Pretreatment: there were no significant differences between intervention and control group regarding age, gender, marital status, weekly working hours, and stressor load before the intervention. Compliance rate: NR Response rate: NR Type of healthcare worker: nurses
Interventions	Intervention characteristics Intervention (resilience) Type of the intervention: Intervention type 4 ‐ Combination of to focus one’s attention on the experience of stress & to focus one’s attention away from the experience of stress Description of the intervention: The training included therapy elements from cognitive behavioural therapy and psychodynamic psychotherapy. Additionally, mindfulness and imagination exercises were included. The aim of the intervention was to provide participants with new skills to help them cope better with individual stressors. The number of sessions: 8 Duration of each session on average: 120 minutes Duration of the entire intervention: 8 weeks Duration of the entire intervention short vs long: Short Intervention deliverer: Psychologist Intervention form: Group Control (no intervention) Type of the intervention: NA Description of the intervention: NA The number of sessions: NA Duration of each session on average: NA Duration of the entire intervention: NA Duration of the entire intervention short vs long: NA Intervention deliverer: NA Intervention form: NA
Outcomes	General Health Questionnaire‐28‐ (GHQ‐28) Outcome type: ContinuousOutcome Mainz Inventory of Microstressors (MIMI) Outcome type: ContinuousOutcome Perceived Stress Scale (PSS) Outcome type: ContinuousOutcome
Identification	Sponsorship source: NR Country: Germany Setting: Hospital Comments: NR Authors name: Gesche Janzarik Institution: Leibniz Institute for Resilience Research Email: pt.janzarik@gmail.com Address: Leibniz Institute for Resilience Research (LIR) Mainz, 55122 Mainz, Germany Time period: NR
Notes	PSS included in analysis 4.1 and 4.2
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "This randomised controlled trial included three assessment points: pre‐test, post‐test, and three follow‐up measurements at three, six, and nine months." Not reported how randomisation took place (e.g. software)
Allocation concealment (selection bias)	Unclear risk	Difficult to judge whether participants and/or investigators could possible foresee assignment. However, it is assumed that randomization was performed in one go and that participants and/or investigators could not foresee assignment.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants were not blinded.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Participants were not blinded whereas outcomes are self‐reported.
Incomplete outcome data (attrition bias) All outcomes	High risk	58 of the 72 (80%) randomised participants responded to the latest follow‐up time included in this review. Reasons provided. Not mentioned whether missing was at random.
Selective reporting (reporting bias)	Unclear risk	No trial registration or no study protocol reported, nor did we find one online.
Other bias	Unclear risk	Compliance rate and response rate not reported.