NCT02867657.

Methods	Study design: RCT Study grouping: parallel Unit of randomisation: individuals Power (power & sample size calculation, level of power achieved): not specified in trial registration Imputation of missing data: not specified
Participants	Country: Denmark Setting: training setting not specified Age: not specified Sample size (randomised): 72 (estimated enrolment) Sex: not specified Comorbidity (mean (SD) of respective measures in indicated, if available) at baseline: not specified Population description: bachelor students at Danish Universities and University Colleges Inclusion criteria: 1) age 18 years and older (adult, older adult); 2) bachelor student at a Danish Universities or University Colleges; 3) a score of 16 or above on the PSS Exclusion criteria: 1) smoking; 2) psychiatric diagnosis (depression, anxiety, adjustment disorder, post‐traumatic stress disorder, personality disorder, psychosis); 3) untreated ADHD, autism, abuse and risk of suicide Attrition (withdrawals and exclusions): not specified Reasons for missing data: not specified
Interventions	Intervention: mindfulness in nature (n randomised not specified) delivery: not specified; probably face‐to‐face providers: not specified duration of treatment period and timing: 5 days description: mindfulness retreat in nature; MBSR curriculum with meditation and yoga compliance: not specified integrity of delivery: not specified economic information: not specified theoretical basis: MBSR Control 1: attention control: mindfulness indoor (n randomised not specified) delivery: not specified; probably face‐to‐face providers: not specified duration of treatment period and timing: 5 days description: mindfulness retreat indoor; MBSR curriculum with meditation and yoga compliance: not specified integrity of delivery: not specified economic information: not specified theoretical basis: MBSR Control 2: wait‐list control (n randomised not specified) delivery: not specified; probably face‐to‐face providers: not specified duration of treatment period and timing: 2 days description: mindfulness retreat in nature is offered 6 months later compliance: not specified
Outcomes	Outcomes collected and reported: Primary outcomes: stress ‐ PSS self‐compassion ‐ SCS Secondary outcomes: mindfulness ‐ FFMQ breath counting ‐ behavioural measurement of attention Nuclear Factor‐kB gene expression Interleukin (IL)‐1 gene expression IL‐6 gene expression C‐reactice protein expression heart rate variability blood pressure Connectedness to Nature Scale Glucocorticoid Receptor gene expression Receptor‐interacting serine/threonine‐protein kinase‐2 gene expression Tumor Necrosis Factror (TNF)‐α gene expression C‐C Motif Chemokine Ligand 5 gene expression IL‐8 gene expression Telomerase reverse transcriptase (TERT) gene expression TERC gene expression IL‐1β protein expression IL‐2 protein expression IL‐4 protein expression IL‐6 protein expression IL‐8 protein expression IL‐10 protein expression IL‐12p70 protein expression IL‐13 protein expression TNF‐α protein expression Interferon‐ɣ protein expression Outcomes reported not specified Time points measured and reported: 1) post‐intervention (at end of 5‐day retreat); time points reported not specified Adverse events: not specified
Notes	Contact with authors: We contacted the authors for the trial status and the potential inclusion of healthcare students, but received no response Study start/end date: June 2016 ‐ November 2018 (estimated completion date according to trial registration) Funding source: VIA University College Declaration of interest: not specified Ethical approval needed/obtained for study: not specified Comments by study authors: not relevant Miscellaneous outcomes by the review authors: unclear if healthcare students were included; trial status unclear Correspondence: Jesper Dahlgaard, PhD; VIA University College, Aarhus, Denmark, DK‐8200; jesd@via.dk; phone: +45 8755 2992