Mueller 2018.

Study characteristics
Methods	Study design: RCT Study grouping: parallel group Unit of randomisation: individuals Power (power & sample size calculation, level of power achieved): power not specified; study limitation: sample size was restricted to a group of 36 physical therapy students in 1 programme Imputation of missing data: information received from authors: per‐protocol analysis with Time 2 and Time 3 following the completion of the intervention by both groups
Participants	Country: USA Setting: online, self‐guided intervention Age: mean = 26.83 (SD = 3.31) years Sample size (randomised): 37 Sex: 25% women, 75% men Comorbidity (mean (SD) of respective measures in indicated, if available) at baseline: not specified Population description: entry‐level doctor of physical therapy (DPT) students Inclusion criteria: not specified Exclusion criteria: not specified Attrition (withdrawals and exclusions): 1 withdrawal in IG (immediate group) Reasons for missing data: for 1 withdrawal in IG: pregnancy‐related delay in internships
Interventions	Intervention: “Called to Care” curriculum (immediate group) (n = 19) delivery: online interactive; each module includes: video lecture, readings, asynchronous discussion board containing 4 ‐ 5 questions pertaining to application of module content; curriculum employs film clips, guided questions, research articles, other readings to promote the clinical application of educational concepts providers: self‐guided intervention; 1 of the authors (KM) monitors discussion board posts duration of treatment period and timing: 10 weeks (intervention completed during first 10‐week internship); access provided to online platform on first day of 1. internship; 11 x 1‐hour modules; participants are able to proceed through modules at their own pace description: 11 evidence‐based, positive psychology‐informed modules; purpose of “Called to Care”: to improve patient outcomes through the development of optimal physical therapist behaviours 11 modules include active constructive responding (Gable 2006), peaked theory (Do 2008) and placebo/nocebo (Colloca 2008; Enck 2008; Kahneman 1993) participants required to post and respond at least once for each of the modules on the discussion board (discussion boards are part of the course, but not systematically analysed) INFORMATION RECEIVED FROM AUTHORS: course developed to improve physical therapist communication, patient outcomes, and work enjoyment; course included sessions on empathy, compassion, making high‐quality interpersonal connections, appreciative inquiry and the use of film as a metaphor for the humanistic side of healthcare compliance: 1/19 withdrew due to pregnancy‐related delay in internships integrity of delivery: not specified economic information: Upon request by author, the developers agreed to provide access to the curriculum at no charge for use with student clinicians for this study theoretical basis: grounded in the science of positive psychology, the study of factors and interventions that support human happiness and well‐being (Adams 2012) developed by Dr Larry Benz (physical therapist with master’s degree in positive psychology) Evidence in Motion. Called to Care course teaches healthcare providers about compassion and empathy. EIM News 14 November 2013. Available at: http://www.evidenceinmotion.com/ about/news/called‐to‐care‐course‐teaches‐healthcare‐providersabout‐compassion‐and‐empathy/ Control: wait‐list control (n = 18) description: delayed intervention group; received the intervention during their second internship compliance: no withdrawals during waiting period in 1. internship
Outcomes	Outcomes collected and reported: empathy ‐ JSEHPS work engagement ‐ UWES‐17 resilience ‐ Grit scale (see Footnotes) Time points measured and reported: 1) pre‐intervention; 2) post‐intervention (after completion of intervention and 1. internship); 3) 10‐week follow‐up in IG (i.e. 10 weeks post‐intervention and after 2. internship) and post‐intervention in CG; for review only 1) and 2) relevant as the wait‐list control had also received the intervention at 3) Adverse events: not specified
Notes	Contact with authors: We contacted the authors for information about the number of participants analysed for the outcomes reported in Table 2 and 3 (i.e. per‐protocol analysis with 36 participants at T2 and T3 and without 1 withdrawal). We also asked for more details about the intervention content (Mueller 2019 [pers comm]). Study start/end date: not specified; Called to Care curriculum provided to all participants at the end of spring 2015 semester Funding source: The authors report no funding or conflicts of interest related to this study Declaration of interest: no funding or conflicts of interest related to this study reported Ethical approval needed/obtained for study: approved by the Northern Arizona University IRB (case 729441‐1) Comments by study authors: not relevant Miscellaneous outcomes by the review authors: additional information about intervention content and number of participants analysed received from authors Correspondence: Dr Karen Mueller; Department of Physical Therapy and Athletic Training, Northern Arizona University, 208 E Pine Knoll Dr, PO Box 15105, Flagstaff, AZ 86011, USA; Karen.mueller@nau.edu
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "participants were randomly assigned (via a blinded shuffle of cards) to an immediate intervention group or a delayed intervention group. The deck included only the numbered cards (to ensure an even 50/50 split) and group assignment based on evens or odds." Quote: "There were no significant differences in age or gender distribution, and no significant differences between the baseline outcome measures of the immediate and delayed intervention groups, suggesting that the randomization worked appropriately." Judgement comment: investigators describe a random component in the sequence‐generation process (shuffling cards); verified baseline comparability of groups for sociodemographic characteristics (all Ps > 0.055) and outcomes of interest on the basis of analysis (see Table 1; Ps > 0.213)
Allocation concealment (selection bias)	Unclear risk	Quote: "randomly assigned (via a blinded shuffle of cards) to an immediate intervention group or a delayed intervention group." Judgement comment: insufficient information about allocation concealment to permit judgement of ‘Low risk’ or ‘High risk’ ("blinded shuffle of cards"; method of allocation concealment is not described in sufficient detail)
Blinding of participants and personnel (performance bias) Subjective outcomes	High risk	Quote: "The participants were informed of their designation into the immediate or delayed intervention group." Judgement comment: online, self‐guided intervention; no blinding of participants and probably no blinding of personnel (monitored discussion board postings); 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 to permit judgment of ‘Low risk’ or ‘High risk’ (in part electronic assessments); but due to 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: "37 students volunteered to participate in the Called to Care study. Of the 37 students, 1 withdrew from the project due to a pregnancy‐ related delay in her internships. Thirty‐six students completed the project." Quote: "FIGURE 1. Study design flowchart." Judgement comment: reasons for missing data unlikely to be related to true outcome (only 1 withdrawal in IG due to pregnancy); information received from authors: "We did perform a per‐protocol analysis with T2 and T3 following the completion of the intervention by both groups."
Selective reporting (reporting bias)	Low risk	Judgement comment: no study protocol or trial registration available but it is clear that the published reports include all expected outcomes, including those that were prespecified