Research Evaluating Staff Training Online for Resilience (RESTORE): Protocol for a single-arm feasibility study of an online Acceptance and Commitment Therapy intervention to improve staff wellbeing in palliative care settings

Background Palliative care staff commonly experience workplace stress and distress. General stressors include unmanageable workloads and staff shortages. Stressors specific to palliative care include regular exposure to death, loss and grief. The COVID-19 pandemic exacerbated exhaustion and burnout across the healthcare system, including for those providing palliative care. Evidence based psychological support interventions, tailored to the needs and context of palliative care staff, are needed. Acceptance and Commitment Therapy (ACT) is an established form of cognitive behavioural therapy which uses behavioural psychology, values, acceptance, and mindfulness techniques to improve mental health and wellbeing. ACT is effective in improving workplace wellbeing in many occupational settings. Our study examines the acceptability and feasibility of an online ACT-based intervention to improve mental health and wellbeing in staff caring for people with an advanced progressive illness. Methods We plan a single-arm feasibility trial. We will seek to recruit 30 participants to take part in an 8- week online ACT-based intervention, consisting of three synchronous facilitated group sessions and five asynchronous self-directed learning modules. We will use convergent mixed methods to evaluate the feasibility of the intervention. Quantitative feasibility outcomes will include participant recruitment and retention rates, alongside completion rates of measures assessing stress, quality of life, wellbeing, and psychological flexibility. Focus groups and interviews will explore participant perspectives on the intervention. We will run a stakeholder workshop to further refine the intervention and identify outcomes for use in a future evaluation. Results We will describe participant perspectives on intervention acceptability, format, content, and perceived impact, alongside rates of intervention recruitment, retention, and outcome measure completion. Conclusion We will show whether a brief, online ACT intervention is acceptable to, and feasible for palliative care staff. Findings will be used to further refine the intervention and provide essential information on outcome assessment prior to a full-scale evaluation.


Methods
We plan a single-arm feasibility trial.We will seek to recruit 30 participants to take part in an 8-week online ACT-based intervention, consisting of three synchronous facilitated group sessions and five asynchronous self-directed learning modules.We will use convergent mixed methods to evaluate the feasibility of the intervention.Quantitative feasibility outcomes will include participant recruitment and retention rates, alongside completion rates of measures assessing stress, quality of life, wellbeing, and psychological flexibility.Focus groups and interviews will explore participant perspectives on the intervention.We will run a stakeholder workshop to further refine the intervention and identify outcomes for use in a future evaluation.

Results
We will describe participant perspectives on intervention acceptability, format, content, and perceived impact, alongside rates of intervention recruitment, retention, and outcome measure completion.

Conclusion
We will show whether a brief, online ACT intervention is acceptable to, and feasible for palliative care staff.Findings will be used to further refine the intervention and provide essential information on outcome assessment prior to a full-scale evaluation.

Introduction
Healthcare professionals working in palliative care settings commonly experience stress and distress [1][2][3] .General stresses include unmanageable workload and staff shortages.Specific stressors occur as a result of caring for patients with complex physical conditions, and regular exposure to death, loss, and grief.In 2020-21, the COVID-19 pandemic led to increased stress and distress within the health and social care workforce [4][5][6][7][8] , including palliative care 9,10 .As a result of the pandemic, healthcare staff encountered rapidly changing clinical roles, new modes of service delivery and increased patient volumes, coupled with risk of infection.A considerable proportion experienced mood and sleep disturbances, raising concerns about risks to mental health 8 .
Despite the occurrence of workplace stress and distress, evidence based psychological support for palliative care staff is lacking.A 2019 Nursing Standard-Marie Curie survey involving 5,346 UK nurses and healthcare assistants involved in end-of-life care, found that one-third reported insufficient support at work to manage grief and emotional stress from caring for dying patients 11 .In 2020, the same survey with 894 respondents, revealed this proportion had increased to 45%, with visiting restrictions due to the pandemic placing additional emotional burden on staff who needed to balance the safety of patients with their needs to be together with their families 12 .A systematic review prior to the pandemic identified only nine papers evaluating psychosocial interventions for palliative care staff and concluded that there was an urgent need to address the lack of intervention development work and high-quality research in this area 13 .Flexible, accessible, scalable and cost-effective psychological support interventions are now more important than ever.
We propose an Acceptance and Commitment Therapy (ACT) based psychological intervention to improve wellbeing, stress, and distress in palliative care staff.ACT is an established form of cognitive behavioural therapy which uses behavioural psychology, values, acceptance and mindfulness techniques to improve mental health and wellbeing 14 .
ACT principles target the kinds of responses that clinicians identify as helpful: being present, finding purpose, acceptance, perspective taking and engaging in life 15 .Recent systematic reviews and meta-analyses show that ACT is efficacious in treating stress, anxiety and depression in a range of settings [16][17][18] , including when delivered online 19,20 .Drawing on evidence of effectiveness in other occupational and healthcare settings 16,17,[21][22][23] , we propose that an ACT-based psychological intervention has strong potential to improve mental health and wellbeing in palliative care staff.
We aim to develop, and test the feasibility of an online ACT-based intervention to enhance workplace wellbeing of staff working with terminally ill and dying patients, and their families.
Our research will answer the following questions: • Is an online ACT intervention feasible and acceptable to palliative care staff?
• What is the experience of palliative care staff undertaking ACT training?
• What are the barriers and facilitators to implementing an online ACT intervention for palliative care staff?
• Is there preliminary evidence that ACT training leads to improvements in workplace wellbeing and stress in palliative care staff?
• What are the implications for future evaluation research, including sample size and outcome measures?

Design
A single-arm feasibility trial of a brief ACT-based intervention for staff providing palliative care for terminally ill adults.We will use convergent mixed methods 24 to evaluate the feasibility of the proposed intervention.

Setting
The study will be hosted by Marie Curie Scotland.Marie Curie is the largest independent provider of end-of-life care and the largest charitable provider of hospice-based care in Scotland.Two Marie Curie hospices, located in Edinburgh and Glasgow, provide short-term inpatient hospice care, outpatient services (including day services), home visits and family support, to terminally ill people and families in their surrounding areas.Across Scotland, the Marie Curie Nursing Service (MCNS) provides care in the last days of life to people in their own homes.

Participants and sample size
Participants will be recruited from two Marie Curie hospices and from the Marie Curie Nursing Service (Scotland).We will seek a sample size of approximately 30 participants.As this is a feasibility study, sample size has not been formally calculated.
Our target sample size is based on prior experience, resources available and the format of the intervention.
Inclusion criteria.The intervention will be offered to health and social care professionals providing direct support to patients and families, including nursing and medical staff, allied health professionals, social workers, and healthcare assistants.

Amendments from Version 1
We have amended this version in accordance with reviewer suggestions.Specifically, we have added a number of references to the research literature on self-compassion in palliative care, to make it clear that this literature has informed the selfcompassion module within the intervention.We have made the nomenclature more consistent, and now use palliative care 'staff' throughout, as opposed to shifting between 'staff' and 'workers'.
We have corrected a typo relating to the description of ProQOL subscales, and have clarified these.We have also added the RESTORE intervention workbook to our ISRCTN record (https:// www.isrctn.com/ISRCTN14313559),where further detailed on course content by week, and related exercised can be accessed.
Any further responses from the reviewers can be found at the end of the article Exclusion criteria.Staff who have previously undertaken Acceptance and Commitment Therapy training will be excluded.

Participant recruitment
Members of the research team will discuss the proposed study with service managers and clinical leads across Marie Curie Scotland.The study will be promoted via hospice newsletters, posters, internal email lists and via relevant Marie Curie internal online forums.The research team will run an online information session for potentially interested participants via MS Teams.
Interested staff members will be directed to seek approval from their line manager in the first instance, if they are interested in taking part.Potentially interested participants will be emailed the participant information sheet, and a link to an online consent form.Following consent, they will be invited to complete an online participant characteristics form (gender; age band; ethnicity; role and number of years' experience in palliative care) which will be used to describe the sample, and stored separately from any outcome data.

Intervention design and content
Location.The online Acceptance and Commitment Therapy (ACT) intervention will be hosted using MS Teams.Participants will be able to join from their usual workplace or home setting.Support will be provided from the research team and the admin team at each hospice for participants who need to access a hospice PC in a quiet location for the purpose of this study.
Facilitation.The intervention will be delivered by a Peer Reviewed ACT Trainer and Fellow of the Association for Contextual Behavioural Science (DG) and facilitated by a research psychologist (AF).DG will lead the virtual classroom sessions.AF will co-ordinate module delivery, manage the online platform and liaise and respond to technical support queries.
Online platform.MS Teams will be used as the training platform, as this supports a range of media, enables chat, and is used widely within health and social care organisations.An MS Team will be set up for intervention delivery, and participants will be invited to join once they consent to the taking part.All participants will be invited to access the online platform in advance of the first session, and individual support, as well as printed resources, will be provided to support access.All intervention materials made available via MS Teams.
Content.The intervention will cover key ACT processes including being present, finding purpose, perspective taking and engaging in life values (Table 1).The content has been informed by previous interventions delivered by the team for health professionals in other settings, as well as research on occupational stress, wellbeing, self-compassion and resilience in palliative care 3,15,[25][26][27][28] .The content is described in a draft manual, which will be revised and shared on the ISRCTN registry on completion of the study.
Format.There will be 8 modules delivered via MS Teams over an 8-week period (Table 1).Delivery will be via three synchronous virtual classroom sessions and five asynchronous, self-directed, e-learning modules.The three virtual classroom modules will be interactive expert-led sessions.The five self-directed e-learning modules will consist of online reading materials, pre-recorded videos, and reflective exercises.
Participants will be encouraged to share experiences with each other and ask questions or seek clarification via the online chat function within MS Teams.Participants will be provided with a workbook (hard-copy) outlining the content for each week alongside related exercises.The workbook can be accessed here: https://doi.org/10.1186/ISRCTN14313559.
Homework.Participants will be asked to complete 'homework' each week to reflect on the material and how it relates to themselves and their work.Homework will be brief and non-obligatory but encouraged.Examples of homework would include practicing brief mindfulness exercises or exercises to enhance compassionate responses.Homework will be described in the workbook.
Adherence.To facilitate adherence, participants will also be sent a weekly reminder to alert them when new content is made available.To facilitate engagement, participants will be encouraged to share their experiences of the intervention, and any questions they might have via the online chat function (within MS Teams).

Benefits of participation.
Participants will receive introductory training in ACT targeted at using this for their own stress management benefit and will be given the opportunity to engage with a range of strategies to improve their workplace and personal well-being over time.

Distress protocol.
It is unlikely that a participant will experience negative consequences as a result of participating in the proposed intervention.However, if a participant does report feeling heightened stress or distress, the course leader, a Clinical Psychologist, will discuss immediate concerns with them, and will signpost them to additional resources and support as appropriate.This may include: i) the Marie Curie Employee Assistance Programme (EAP) which includes practical information and emotional support guidance as well as access to trained counsellors, ii) to their line manager or HR manager if appropriate, iii) to a Marie Curie hospice-based Clinical Psychologist.Any unintended harms will be recorded by the Co-Principal Investigators and described as part of the research findings.
Ancillary and post-trial care.Should any participant express a need for additional or continued psychological support on completion of the intervention, they will be directed to additional support, in line with the distress protocol.

Data collection, analysis and management
Quantitative data collection.Five key outcomes will be assessed prospectively, via JISC online survey (www.onlinesurveys.ac.uk) at four time-points -before commencement of the intervention, mid-way through the intervention, on completion of the intervention and one-month post-completion.(Table 2).This will allow examination of preliminary evidence for changes in outcomes collected by questionnaire over the course of the intervention, as well as questionnaire completion rates to inform the design of a future evaluation.As we are most interested in changes in outcomes that are sustained beyond intervention delivery, our main exploratory analysis will focus on the change in outcomes pre-intervention versus 4 weeks post intervention.This data will help us identify key outcomes and sample size needed for a future evaluation Self-reported, perceived stress will be assessed by the Perceived Stress Scale (PSS) 29,30 .This scale assesses participants' appraisals of stressful situations, including perceptions of how unpredictable, uncontrollable, and overloaded their lives have been over a defined period.We will use the 10-item scale consisting of a Perceived Helplessness subscale (6-items) and a Perceived self-efficacy subscale (4-items) 30 .
Workplace quality of life will be assessed by the Professional Quality of Life scale (ProQol) 31 .The ProQOL consists of 30 items in three subscales (10 items per subscale) designed to measure compassion satisfaction (pleasured derived from doing your work well), burnout and secondary trauma.Each item rates the frequency of an experience on a scale from 0 (never) to 5 (very often).
Wellbeing will be assessed using the Edinburgh Warwick Mental Wellbeing Scale 32,33 .This is a 14-item scale, covering both hedonic and eudemonic aspects of mental health including positive affect, satisfying interpersonal relationships and positive functioning.Higher scores reflect increased wellbeing.
Healthcare professional experience will be assessed by the Mindful Healthcare Scale which assesses engagement, awareness and defusion -13 items.This measure is being developed at the University of Edinburgh 3,34 .
Psychological flexibility will be assessed by the CompACT. 35t consists of 23 items over 3 sub-scalesopenness to experience, behavioural awareness, and valued action.Participants are asked to rate the degree to which a statement is true for them using a 7-point scale.The higher the score, the higher participant's level of psychological flexibility.
Feasibility outcomes will be assessed retrospectively via routine data collection on completion of the intervention and qualitative data collection.Data will include: • the number of participants recruited (target is 24 -30 participants), • the number of participants who complete the intervention, i.e. participant attended the final session or reported they had completed at least 6 of 8 modules (target is two-thirds of those who completed the intervention) • the number of participants who complete the outcome measures (target is at least two-thirds of those who commence the intervention).
• The number of participants who take part in post-intervention focus groups or interviews (target is 50-75% of those recruited, given that focus groups will be run during work time and some participants will be unable to take part due to work schedules and annual leave).
We will also explore stress levels at baseline to determine whether those with moderate to high levels of stress were recruited and examine any potential links between baseline stress and participant retention.
Qualitative data collection.We will conduct virtual focus groups with participants one month following completion of the intervention to explore their experience of ACT training; views on what elements were most and least useful; perception of any changes in how they manage challenging situations; and whether/in what way skills learnt during the training might improve the care they provide to patients and families.All participants will be invited to take part.Focus groups will be run via MS Teams, recorded, and transcribed for analysis.Qualitative data will be collected by an experienced qualitative researcher (BS), based at a different institution to participants, and not personally known to participants prior to data collection.Participants who drop-out will be invited to share their reasons via brief interview.With permission, the interview will take place via MS Teams, and will be recorded and transcribed.Where participants drop-out and choose not to take part in an interview, we will ask permission to note their main reason(s) for drop-out.

Quantitative and qualitative data analysis.
The main quantitative outcomes of interest are feasibility outcomes which will include rates of participant recruitment and retention over the course of the study.As this is a feasibility trial, it is likely to be underpowered to detect statistically significant improvements in the non-feasibility outcomes (e.g.stress, quality of life, wellbeing) and so these will be reported descriptively (mean, standard deviation, range etc.).Instead, the outcome data collected will help ascertain whether there is any preliminary evidence for intervention effectiveness.It will be also used to estimate effect sizes and determine sample sizes for a future full-scale evaluation.Any missing data will be handled using pairwise deletion methods.We are most interested in any evidence for improvements in outcomes between pre-intervention baseline (T0) and post-intervention follow-up (T3).Data will be analysed in IBM SPSS Statistics, V24.Qualitative data analysis will be guided by the framework approach using NVivo 12 36 and will provide vital insights on intervention acceptability, perceived effectiveness and recommendations for further refinement.

Stakeholder workshop to cross-validate emergent findings, refine the intervention and identify considerations for future full scale evaluation and implementation.
A stakeholder workshop will be organised, bringing together participants, members of the research team, staff managers and those who would be involved in intervention delivery if it were implemented, to discuss findings.At this workshop participants will have the opportunity to highlight themes that resonate with them, as well as those that do not, and identify anything that may have been missed.We will review feasibility data and seek feedback on how the intervention could be further refined to meet the needs of palliative care staff in the organisational context in which the intervention would be implemented.We will explore costs and resource use from multiple perspectives and consider short and long terms outcomes for consideration in a future full-scale evaluation.

Data management
Personal data.Personal data (participant name, email address, age band, gender, role, years working in palliative care) will be stored in a secure file in the University of Edinburgh DataStore.This is password protected and encrypted storage.
Participants will be allocated a Participant ID for the study.
The Participant ID will be used when completing the online questionnaire.Outcome data will be kept separate from personal data throughout the study.The code break file will be held in a separate password protected folder within the DataStore only accessible by the Co-Principal Investigators (AF and DG).

Transfer of data.
Focus group and interview data collected at the host organisation (Marie Curie) will be stored in a secure location on MS Teams, accessible only to participants and the research team (and deleted once transcription has taken place).Data will be anonymised and transcribed by a member of the research team, and then transferred via secure email to the University of Edinburgh DataStore.

Data storage.
All date files will be stored in a secure location -the University of Edinburgh DataStore.Personal data will be held for no longer than 2 years after completion of the study.The Co-Principal Investigators will be responsible for deletion of data.Anonymised data will be retained indefinitely to inform future research.
Confidentiality.Participants will be allocated a Participant ID following recruitment.The Participant ID will be used when completing online questionnaires throughout the study.The Participant ID will be linked in one stand-alone file held in the DataStore, and only accessed if the participant has forgotten their ID and needs to be reminded.We do not plan any analysis that would potentially identify a participant, however, if there is any chance of this occurring, we will collapse the small group data in the final anonymised file, so there is no chance of identification (e.g.If only one male participated, outcome data by gender would be amalgamated.)Participants will be known to each other but will be reminded throughout the study that all discussions should remain confidential.

Monitoring
Role of sponsor and funder.The Co-Principal Investigators (AF and DG) are employees of the sponsor organisation (University of Edinburgh) and have honorary contracts at the host site (Marie Curie).They will have a direct role in study design; collection, management, analysis, interpretation of data; writing of the report; and the decision to submit the report for publication.The study is funded by Marie Curie: www.mariecurie.org.uk.

Data controller, breaches and monitoring. The University of
Edinburgh is the data controller for this study.Any data breaches will be reported to the University of Edinburgh Data Protection Officers who will onward report to Marie Curie, according to the appropriate timelines, if required.As this is a low-risk single-arm feasibility study, a data monitoring committee is not required.

Ethics and dissemination
Research ethics and governance approvals.We obtained ethical approval from the University of Edinburgh Clinical Psychology Research Ethics Committee on 20/5/2021 (Ref: CLPS021s).This research was also approved by the Marie Curie Research Governance Committee in Scotland.
Protocol registration and amendments.Any protocol amendments will be communicated to i) the sponsor, ii) the University of Edinburgh Clinical Psychology Research Ethics Committee, and iii) the Scottish Marie Curie Research Governance Committee, in a timely manner.The study protocol was registered on the ISRCTN registry, and any protocol amendments will be available there (https://doi.org/10.1186/ISRCTN14313559).

Dissemination policy
Research findings will be disseminated via publication in an open access academic journal, a report for the funder, social media and conference presentation.To accelerate dissemination, we will share study findings on a pre-print server (e.g.Medrxiv) at the same time as we submit to a journal.We will share preliminary findings (e.g.poster presentations) and related study material (e.g.study protocol) on AMRC Open (https://www.amrc.org.uk/), an open access platform for the dissemination of research funded by medical research charities.
Authorship of research papers will be agreed in line with ICMJE recommendations.http://www.icmje.org/icmjerecommendations.pdf.

Conclusions
The RESTORE study represents the first step in a programme of research to examine the effectiveness of ACT-based approaches to improve mental health and wellbeing in health and social care professionals caring for people with an advanced illness.It will yield findings on the acceptability and feasibility of an online ACT intervention for palliative care staff, including the aspects of the intervention most valued, and the outcomes most useful to measure in future studies.Our findings will inform the development of a future large scale evaluation examining intervention effectiveness on staff mental health and wellbeing, cost effectiveness and broader impacts within the wider health and social care system.

Study status
Data collection is currently underway, and will be completed in December 2021.Data analysis will take place in January 2022, and the stakeholder workshop will take place soon after.
The study is scheduled to conclude in March 2022.
efficacy.Design: The rationale for the non-randomised, single-arm design, and the decision to not include a 'wait-list' or similar control (to facilitate randomisation, control for within participant differences, and establish between group effects) was not clear and would be useful to include.
○ Fidelity: Some detail regarding how fidelity to the ACT model (within the online sessions) is to be assessed would be useful (e.g., independent review of online seminars using the ACT-FM).This is particularly salient given that session seven within the protocol suggests a focus on 'Compassion' (which may adhere more closely to Compassion-Focused Therapy rather than traditional ACT).

○
Measures: To lessen participant burden, the authors may wish to consider the short versions of the WEMWBS and CompACT.
○ Adherence: Will homework compliance etc., be formally monitored (to determine adherence to, and 'dose' of, the intervention)?
○ Data collection: The authors may not be aware that the JISC platform (at the time of writing) does not appear to allow analysis of partial or incomplete responses ( https://www.onlinesurveys.ac.uk/help-support/can-i-see-partial-or-incomplete-responses/).This appears to be a severe limitation of the platform, particularly when undertaking feasibility research.The authors state here their aim to determine the number of participants who complete the measures; however, partial, incomplete, and unfinished survey responses cannot be accessed -only the page where a participant ceased participation can be determined.

Anne Finucane
Thank you very much for the helpful comments and suggestions.These will be very informative as we plan follow-up work.We have provide some additional justifications and clarifications in response to your comments below.We did not specify a primary outcome or pre-screen participants as this was a smallscale feasibility study.We were keen to explore a range of outcomes to see which might be most suitable for inclusion in future large-scale evaluations.We were also unsure about the extent to which would be able to recruit participants in light of COVID, so were hesitant to pre-screen participants, but we will explore the question of whether or not to pre-screen in future studies as we analyse the data collected and share the findings with stakeholders. 1.
As this was a small-scale study, undertaken during the COVID pandemic, we were keen to keep it simple.We did not have the capacity to link in with clinical trials unit, and to randomise participants.However, we agree with Reviewer 2 that this will be essential in future studies.

2.
Thank for this useful suggestion which we will need to consider for future studies.For the present study, the intervention was delivered by a Peer Reviewed ACT Trainer and Fellow of the Association for Contextual Behavioural Science, but for future studies we will need to consider fidelity assessments.

3.
We aimed to collect data via focus groups as this method allows the generation of a range of responses regarding the intervention in an efficient and pragmatic manner.Furthermore, participants were used to exchanging views in a facilitated group format, and while we appreciate that in some instances this can hinder the freedom with people exchange views, given the nature of the topics covered in the focus groups, it was felt that the benefits of the group interaction and sharing of ideas outweighed this.We also offered interviews to participants who did not complete the intervention.Given the timing of intervention delivery (during the height of the COVID pandemic) offering a variety of participation approaches, while minimising overall staff time commitment, was important.

4.
Thank you for the helpful suggestion in relation to using shorter assessment tools which we will consider in future studies.

5.
Adherence was monitored via self-report questionnaires and explored further during qualitative data collection.

6.
We set up 4 separate questionnaires to gather data at each timepoint; and merge on completion of data collection (using participant ID not linked to the participants name) -any limitations of the JISC platform have not been a problem.

7.
Thank you for the helpful suggestion in relation to the RE-Aim framework.8.
Competing Interests: AF is supported through a fellowship funded by the host organisation (Marie Curie).JS and BL are employed by the funder.DG, BS and NHW declare no financial relationships with any organisations that might have an interest in the submitted work in the previous 3 years.I commend the researchers on their efforts in this important area.
Based on my experience as an ACT practitioner, as well as my knowledge and understanding of the palliative care field, I believe this paper proposes an important study of considerable merit given the past and ongoing impacts of the COVID-19 pandemic on the study population.
Overall, the rationale and objectives of the study are mostly described in a clear way.However, from my review, there are some important considerations for minor revision and the future conduct/reporting of the study.These are outlined further below.This single-arm trial incorporating a mixed-methods convergent design is appropriate for the broad research questions being addressed in this study, with the mixing of quantitative and qualitative data representing a strength.Consideration of improving consistency in research question nomenclature is recommended (the terms 'palliative care workers' and 'palliative care staff' are used interchangeably).
Details of research methods are sufficient for a protocol at this stage, although there is scope to strengthen the reporting of the intervention content/format when finalising the 'draft manual' prior to sharing on the ISRCTN registry.
How was the content developed and how is the content/format justified?These details appear to be missing from the protocol.On p.4 the reader is informed that 'the content has been informed by previous interventions delivered by the team for health professionals in other settings, as well as research on occupational stress, wellbeing, and resilience in palliative care' -however, there are no intervention reference sources or research reports cited in this sentence to substantiate or support this claim.To this end, there is a need to draw more direct linkage between self-compassion and the ACT intervention.
While it is pleasing to see the inclusion of intervention content focused on compassion for self and others (Module 7), from my review this content has not been adequately justified and/or situated within the context of those working in palliative care.The relevance and remit of self-compassion in hospice and palliative care has been systematically reviewed by Garcia et al (2021) 1 .
Given the focus of module 7 and the homework exercises intended to 'enhance compassionate responses' in participants, it is recommended that the authors include some reference to the relevant literature to justify/better situate this important content as part of the intervention.This is pertinent since that module is self-directed rather than facilitated, and past research in this area has indicated compassion for self does not come naturally and can be challenging for some people working in palliative care.The Module 8 'Review and trouble-shooting' session might best begin with acknowledging this known challenge and inviting discussion of any challenges/barriers experienced.

Important correction required:
There is an error requiring correction on p.5 (Data collection, analysis and management)under the heading of 'Workplace quality of life' it is stated that 'The ProQOL consists of 30 items in three subscales (10 items per subscale) designed to measure compassion, satisfaction, burnout, and compassion fatigue'.However, this instrument does not measure compassion and it was not designed to do so.Apart from BO and CF, the ProQOL measures 'compassion satisfaction' (CS) which is quite distinct from compassion itself.Perhaps this was a typo -with an erroneous comma in between 'compassion' and 'satisfaction'?Please correct this sentence for veracity.1.
Consider improving consistency in the nomenclature used in the stated research questions (the terms 'palliative care workers' and 'palliative care staff' are used interchangeably).

2.
Very best wishes for progressing this work.

○
It would be useful to provide a rationale for the use of focus groups (over individual interviews) given the impact dominant voices can have on group consensus etc.○Stakeholder Workshop: We have found the RE-AIM framework useful for structuring discussions around how health interventions might be refined (https://reaim.org/learn/what-is-re-aim/)and the authors may find some utility there too.○Is the rationale for, and objectives of, the study clearly described?YesIs the study design appropriate for the research question?PartlyAre sufficient details of the methods provided to allow replication by others?YesAre the datasets clearly presented in a useable and accessible format?PartlyCompeting Interests: No competing interests were disclosed.Reviewer Expertise: Clinical Psychology; Applied Clinical Research; Behaviour Analysis; Behaviour Change I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.

Reviewer Report 15
December 2021 https://doi.org/10.21956/amrcopenres.14110.r26868© 2021 Mills J.This is an open access peer review report distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Jason Mills School of Nursing, Midwifery and Paramedicine, University of the Sunshine Coast, Caboolture, Qld, Australia This article reports the RESTORE study protocol -Research Evaluating Staff Training Online for Resilience (RESTORE) -seeking to examine the feasibility and acceptability of an Acceptance and Commitment Therapy (ACT) intervention designed to improve mental health and wellbeing for those working within palliative care contexts.

○
Recommended minor revisions:As above, please consider drawing reference to the relevant literature on self-compassion in palliative care to justify and better situate its explicit inclusion as key content (Module 7) within the ACT intervention.See for example: Garcia et al. (2021).https://journals.lww.com/jhpn/Abstract/2021/04000/Self_compassion_In_Hospice_and_Palliative_Care__A. 1 .

Table 1 . Overview of intervention content.
Synchronous online virtual classroomLed by an ACT trainer (DG)