Smeets 2014.

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 Imputation of missing data: unclear if available‐case analysis (with n = 49 as indicated in text) or if missing data were imputed to perform intention‐to‐treat analysis
Participants	Country: Netherlands Setting: mid‐sized European University Age: mean = 19.96 (SD = 1.33) years Sample size (randomised): 52 Sex: 52 women Comorbidity (mean (SD) of respective measures in indicated, if available) at baseline: not specified Population description: female psychology students entering first or second year of college Inclusion criteria: not specified Exclusion criteria: not specified Attrition (withdrawals and exclusions): only CG: 3/25 (12%) did not complete post‐test assessment and were excluded from analysis (according to text; but see also Table 2 in the report) Reasons for missing data: not specified
Interventions	Intervention: self‐compassion (SC) intervention (n = 27) delivery: face‐to‐face; group sessions; each intervention session: short presentation followed by experiential exercises and discussion periods; intervention booklet providers: all sessions co‐led by 2 trainers (including first author) duration of treatment period and timing: 3 weeks; 2 x active 1½‐hour intervention sessions; 1 x 45‐minute closing/evaluation session description: goal: to equip participants with the ability to treat themselves compassionately in times of personal suffering WEEK 1/SESSION 1: focused on teaching participants to notice own suffering and introduction of informal self‐compassion techniques; background information on self‐compassion and its differences from concepts (e.g. self‐indulgence, self‐pity, self‐esteem); participants share experiences on how they usually treat themselves when having a difficult time and explore their self‐critical voice by writing down their most common self‐critical thoughts on cards; participants are asked to think about what they would need to feel comforted and understood in times of distress HOMEWORK ASSIGNMENTS: a) “intervention bracelet”: switch from one arm to the other every time they addressed themselves in a harsh way or felt upset about something; b) keep week‐long “self‐compassion journal” that contains instructions on how to reprocess difficult experiences with a sense of kindness, common humanity, and mindfulness; and c) loving‐kindness meditation: silently repeat 3 loving‐kindness phrases directed to others, themselves, every night before going to bed (e.g. “may you be at peace,” “may you be kind to yourself,” “may you be free from suffering”) WEEK 2/SESSION 2: focused on teaching participants to be more self‐compassionate when confronting difficulties in daily life; presentation on the role of self‐criticism in fear of failure and procrastination; think about what motivates themselves in a self‐compassionate rather than a self‐critical way; exercise: design of 3 personalised self‐compassion phrases to use when encountering difficulties in daily life that correspond to key elements of self‐compassion definition (e.g. “This is a moment of suffering” (mindfulness), “suffering is something we all share” (common humanity), and “may I be kind to myself” (self‐kindness ); write down 5 things they appreciate about themselves and discussion of experience of relating to oneself in a positive way HOMEWORK ASSIGNMENT: a) use self‐compassion phrases as often as possible when encountering difficulties in daily life; b) write a self‐compassionate letter about an issue they tend to feel bad about (written from perspective of imaginary friend who is unconditionally kind, accepting and compassionate) that is read twice in upcoming week; c) continue with loving‐kindness practice every night WEEK 3/SESSION 3: sharing of experiences and evaluation of intervention compliance: not specified integrity of delivery: not specified economic information: not specified theoretical basis: self‐compassion literature (e.g. Neff 2003b) Control: attention control (time management control intervention) (n = 25) delivery: face‐to‐face; group sessions; each intervention session: short presentation followed by experiential exercises and discussion periods; intervention booklet providers: all sessions co‐led by 2 trainers (including first author) duration of treatment period and timing: 3 weeks; 2 x active 1½‐hour intervention sessions; 1 x 45‐minute closing/evaluation session description: goal: to teach participants general time management skills WEEK 1/SESSION 1: focus on teaching participants to become aware of the way they manage their time; background information on time management; participants share experiences on how efficiently they use their time; exercise: write down detailed overview of daily activities of the past work week, along with estimation of time they had spent on each activity; give time efficiency percentages, reflecting how efficiently they had used their time for each activity; brainstorming about explanations for lowest and highest efficiency percentages; participants introduced to use of visualisation for optimising their time management skills and asked to visualise their activities of the last 24 hours by means of short visualisation audio fragment HOMEWORK ASSIGNMENTS: a) write down all daily activities along with time estimation and time efficiency percentage, every evening of upcoming week; b) evaluate time management satisfaction and reflect on potential reasons for effectiveness and ineffectiveness; and c) compare time efficiency percentages across days WEEK 2/SESSION 2: focused on helping participants to plan their time more efficiently; participants receive “time management” reminder bracelet to remind them of their practice; presentation on importance of making a week planning; group discussion in which participants talked about how they usually plan their days; participants make detailed planning of their activities for each day of the upcoming work week and are told to specify ways that could help them carry out their activities more efficiently; participants estimate how much time they would spend on each of their activities HOMEWORK ASSIGNMENTS: see work 1 WEEK 3/SESSION 3: sharing of experiences and evaluation of intervention compliance: not specified integrity of delivery: not specified economic information: not specified theoretical basis: not specified
Outcomes	Outcomes collected and reported: self‐compassion ‐ SCS mindfulness, accept without judgement ‐ subscale Kentucky Inventory of Mindfulness Skills (KIMS‐E) mindfulness, nonreactivity to inner experience ‐ subscale KIMS‐E life satisfaction ‐ SWLS connectedness ‐ Social Connectedness Scale‐Revised optimism ‐ Life Orientation Test‐Revised self‐efficacy ‐ General Self‐Efficacy scale positive affect ‐ PANAS negative affect ‐ PANAS rumination ‐ Ruminative Response Scale‐NL‐Extended worry ‐ Penn State Worry Questionnaire Time points measured and reported: 1) pre‐intervention (1 week before intervention); and 2) post‐intervention (1 week after intervention) Adverse events: not specified
Notes	Contact with authors: We contacted authors to ask if missing data had been imputed to perform intention‐to‐treat analysis (according to text: n = 49 analysed due to exclusions; Table 2: n = 52 analysed), but they had not responded at the time of writing this review Study start/end date: not specified Funding source: not specified Declaration of interest: not specified Ethical approval needed/obtained for study: approved by the local committee for research ethics Comments by authors: not relevant Miscellaneous outcomes by the review authors: not relevant Correspondence: Elke Smeets; Department of Clinical Psychological Science, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands; elke.smeets@maastrichtuniversity.nl
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "All participants were randomly assigned to either the self‐compassion intervention group (N = 27) or the time management control group (N = 25) by means of an Internet‐based randomization program (www.randomizer.org)." Quote: "Analyses of variance procedures (ANOVAs) were employed to examine whether there were significant differences between the self‐compassion intervention group and the time management control group on study measures at pretest. ANOVA’s revealed no significant differences between groups on any of the pretest or demographic measures (all Fs < 2.54, all ps < .05)." Judgement comment: The investigators describe a random component in the sequence‐generation process (internet‐based randomisation); verified baseline comparability of groups for sociodemographic characteristics and outcomes on the basis of analysis
Allocation concealment (selection bias)	Unclear risk	Judgement comment: 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: blinding of participants and personnel 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: 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 intervention they received)
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "The initial sample comprised 52 female psychology students" Quote: "Three control participants did not complete posttest measurements and were excluded from analyses, leaving a final sample size of 49 participants (N = 27 in the intervention group, and N = 22 in the control group)." Judgement comment: reasons for missing outcome data likely to be related to true outcome, with (slight) imbalance in numbers of missing data between groups (IG: n = 0; CG: n = 3); reasons for missing data not reported; unclear if available case analysis (with n = 49 as indicated in text) or if missing data were imputed to perform intent‐to‐treat analysis (see Table 2)
Selective reporting (reporting bias)	Low risk	Judgement comment: no study protocol available but it is clear that the published reports include all expected outcomes, including those that were prespecified