Chen 2018a.

Study characteristics
Methods	Study design: RCT Study grouping: parallel group Unit of randomisation: individuals Power (power & sample size calculation, level of power achieved): not specified in conference abstract Imputation of missing data: probably no imputation of missing data; only 9 did not withdraw and completed all surveys, i.e. yielding an analytic sample of 9 (due to small sample size, no analysis of hypotheses)
Participants	Country: USASetting: not specifiedAge: not specified Sample size (randomised): 22Sex: not specifiedComorbidity (mean(SD) of respective measures in indicated, if available) at baseline: not specified Population description: fall and spring first‐semester baccalaureate students in nursing (BSNs) Inclusion criteria: not specified Exclusion criteria: not specified Attrition (withdrawals and exclusions): n = 9/22 withdrawals (not specified which group); 9 of 13 remaining participants completed all surveys (not specified which group), i.e. 4 with incomplete surveys Withdrawals and exclusions: 9/22 withdrawals (not specified which group); 9 of 13 remaining participants completed all surveys (not specified which group), i.e. 4 with incomplete surveys
Interventions	Intervention: Brief Mindfulness‐based Compassion (MSC) (n randomised not specified) delivery: face‐to‐face (setting not specified) and individual home practice providers: not specified duration of treatment period and timing: 4 weekly 1‐hour sessions + 10 minutes daily home practice description: emphasises self‐kindness compliance: total withdrawal: 9 (unclear which group) integrity of delivery: not specified in conference abstract economic information: not specified in conference abstract theoretical basis: mindfulness‐based Control: wait‐list control (n randomised not specified) description: receive consolidated half‐day programme at the beginning of the following semester compliance: total withdrawal: 9 (unclear which group)
Outcomes	Outcomes collected and reported: stress ‐ scale not specified resilience ‐ scale not specified mindfulness ‐ scale not specified self‐compassion ‐ scale not specified academic performance ‐ scale not specified; not reported Time points measured and reported: 1) pre‐intervention; 2) post‐intervention; 3) 1‐month follow‐up (at 8 weeks after baseline, i.e. 4 weeks after 4‐week intervention); time points reported not specified Adverse events: not specified
Notes	Contact with authors: We contacted the authors to see if the study was already published (Kelleher 2019 [pers comm]). Study start/end date: not specified Funding source: not specified Declaration of interest: not specified Ethical approval needed/obtained for study: not specifiedComments by study authors: not relevantMiscellaneous outcomes by the review authors: not relevantCorrespondence: Catherine Kelleher; University of Maryland, School of Nursing; kelleher@umaryland.edu
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote (see conference abstract): "During year 1, participants were randomized to MBSR and MSC programs as originally planned but enrollment was low. During year 2, the randomized design was modified to drop the MBSR arm, focus only on the MSC program, and use a control group in which participants would get the MSC program in a consolidated half‐day program at the beginning of the following semester. The simplified design permitted testing student interest in signing up for an MSC study and the impact on enrollment if there was no uncertainty about being randomized to 1 of 2 programs which met at different times." Judgement comment: based on conference abstract, insufficient information about random‐sequence generation to permit judgement of 'Low risk' or 'High risk'; no judgement on baseline comparability possible
Allocation concealment (selection bias)	Unclear risk	Judgement comment: based on conference abstract, insufficient information about allocation concealment to permit judgement of 'Low risk' or 'High risk'.
Blinding of participants and personnel (performance bias) Subjective outcomes	High risk	Judgement comment: based on conference abstract, blinding of participants probably not done (face‐to‐face intervention) and the outcome is likely to be influenced by lack of blinding
Blinding of outcome assessment (detection bias) Subjective outcomes	High risk	Judgement comment: based on conference abstract, insufficient information about blinding of outcome assessment; but due to potential performance bias (no blinding of participants), the review authors judge that the participants' responses to questionnaires may be affected by the lack of blinding (i.e. knowledge and beliefs about the intervention they received)
Incomplete outcome data (attrition bias) All outcomes	High risk	Quote (see conference abstract): "In year 2, total recruitment=22, total withdrawal=9, and 9 of the 13 participants completed all surveys, yielding an analytic sample=9. Due to small sample size, analysis for both pilot years was limited to descriptive statistics, and hypotheses could not be tested" Judgement comment: unclear if reasons for missing data likely to be related to true outcome (number of participants randomised to each group and number of dropouts in each group not stated); probably per‐protocol analysis and available‐case analysis (analyses restricted to descriptive statistics and no testing of hypotheses due to withdrawals and incomplete surveys; i.e. only 9 participants who did not withdrew and completed the surveys were considered)
Selective reporting (reporting bias)	Unclear risk	Judgement comment: no judgement possible based on conference abstract