Registered Nurses' and nursing students' perspectives on moral distress and its effects: A mixed‐methods systematic review and thematic synthesis

Abstract Aim To examine Registered Nurses (RNs') and nursing students' perspectives on factors contributing to moral distress and the effects on their health, well‐being and professional and career intentions. Design Joanna Briggs Institute mixed‐methods systematic review and thematic synthesis. Registered in Prospero (Redacted). Methods Five databases were searched on 5 May 2021 for studies published in English since January 2010. Methodological quality assessment was conducted in parallel with data extraction. Results Searches yielded 2343 hits. Seventy‐seven articles were included. Most were correlational design and used convenience sampling. Studies were mainly from North America and Asia and situated in intensive and critical care settings. There were common, consistent sources of moral distress across continents, specialities and settings. Factors related to perceived inability or failure to enact moral agency and responsibility in moral events at individual, team and structural levels generated distress. Moral distress had a negative effect on RNs health and psychological well‐being. Patient or Public Contribution No patient or public contribution to this systematic review.


| Search strategy, study selection and data extraction
The search strategy was developed and tested in collaboration with a specialist health service systematic review librarian (EG). On 5th May 2021, one reviewer (ET) systematically searched the electronic databases MEDLINE, PsycINFO (via OvidSp), CINAHL (via EBSCO host), Embase (via Elsevier) and the Web of Science for studies published in English since 2010. This review was commissioned in the early stages of the SARS-CoV-2 pandemic. Given our timescales, the decision to run the searches between 2010 and 2021 was pragmatic, and taken in consultation with information specialists to ensure relative stability in the healthcare context within which nurses were working and experiencing moral distress. A combination of Medical Subject Headings (MeSH) search terms was used including moral*, distress, suffering, injury, residue, psychological distress, nurse and nurses. To enhance the sensitivity and refine the searches, Boolean operators (OR and AND) were used. A detailed description of the search strategies used in each database is presented in the online supplementary material (File S1). All hits were entered into EndNote and duplicates removed. Remaining hits were imported to Covidence SR management software. Additional duplicates were identified and removed.
All project team members were involved in the screening and selection process. Standardised systematic review methods (Centre for Reviews & Dissemination, 2009) were used. Firstly, two reviewers independently screened returned titles and abstracts, sifting these into a 'yes', 'no' or 'maybe' category. Where a definite decision based on title and abstract alone could not be made, the full text was retrieved and assessed. Secondly, full text of all potentially relevant abstracts were retrieved and independently assessed for inclusion by reviewers against the purposively designed eligibility criteria.
Uncertainties for both first-and second-level screening were resolved by the two reviewers. In the event of disagreement, an independent reviewer would arbitrate. However, arbitration was not required. Reasons for exclusion at full text review were recorded. Data were extracted systematically using an adapted JBI mixed-methods data extraction form and Covidence software. A second reviewer independently cross-checked all data extraction forms for accuracy, integrity and completeness. To establish concordance, a third reviewer independently moderated a sample (10%) of extracted data. Extracted data included the author(s), year and country of publication, study aim and design, setting, number and characteristics of participants, approaches to sampling, data collection, analysis and quality appraisal outcome.
In preparation for analysis and to facilitate the comparison and contrast of study findings systematically and coherently, for each study, a brief, textual, narrative summary reporting key findings relevant to the review questions was written.

| Quality appraisal
Two reviewers independently assessed the quality of included studies using the Mixed Methods Appraisal Tool (MMAT) version 18 (Hong et al., 2018). The MMAT was constructed specifically for quality appraisal in mixed studies reviews (Hong et al., 2018;Pace et al., 2012). Each study was assigned a score based on the number of criteria met (25%-one criterion met; 100%-all criteria met).
Studies were excluded if they met none of the quality criteria.

| Data analysis and synthesis
Findings from qualitative, quantitative and mixed-methods studies were synthesised thematically to address the review questions. The textual narrative summaries created during data extraction were aggregated and checked (TW). Guided by Thomas and Harden's (2008) approach to thematic synthesis, two researchers (TW, BJ) read and reread the aggregated textual summaries and corresponding articles. Initial, descriptive inductive codes were generated independently. Patterns within and between the studies were identified and following consultation with other team members for rigour.

| Study populations
The majority of included studies (n = 77) were conducted in North Most studies (n = 62) focused on moral distress among nurses in hospital settings specifically: intensive care (n = 14), critical care (n = 8), emergency departments (n = 7), haematology and oncology units (n = 5) and psychiatric units (n = 6). Six studies were conducted in universities with nursing students.

| Study quality
Eight of the 29 qualitative studies (28%) and seven of the 42 quantitative studies (17%) fulfilled all four MMAT quality criteria. None of the mixed-methods studies fulfilled all MMAT quality criteria.

| 'Nobody listens': Relational dynamics and practices within intra and interprofessional teams
In morally challenging situations where patients' dignity, outcomes and optimal care were threatened and patient suffering occurred, col- We're trained to vocalize our concerns and ask the hard questions and debate, but we're reprimanded for that by our managers. (Ritchie et al., 2018, p RNs articulated that failing to speak up intensified their moral distress experience, particularly when care standards fell below their personal and professional practice standards, and they felt complicit in prolonging suffering (Deady & McCarthy, 2010). To mitigate moral distress in such circumstances, the importance of postincident team reflection was recognised (Deady & McCarthy, 2010).
Yet, within and between teams, inadequate or insufficient communication, consultation and collaboration were identified as common  Nursing students reported that their practice experiences, including witnessing outdated best practice (Renno et al., 2018) and being unsupported regarding their concerns did not live up to the view of nursing to which they were being socialised (Wojtowicz et al., 2014), and contributed to moral distress.
Privileging routinised, task-orientated approaches to care "The patient needed blood. There was a need to collect blood from a blood bank of another institution but there was no transport. Patient's condition deteriorated. I felt very bad." (Maluwa et al., 2012, p. 200: Malawi, various settings)

| 'I'm totally overwhelmed': The effects of moral distress on nurses
The moral distress derived from RNs' perceived inability to act in accordance with core professional values and optimise timely, safe, effective high-quality person-centred holistic care generated adverse biopsychosocial sequalae. Furthermore, findings from numerous studies indicated how the experience of frequent and intense moral distress impacted negatively on their professional intentions. By way of contrast, there were no reports of the effects of moral distress on nursing students in the six studies retrieved.
However, not all RNs who had experienced moral distress left or considered leaving their positions (Borhani et al., 2014;Evanovich Zavotsky & Chan, 2016). Some used moral distress as a learning experience to drive them. For example, a subsection of participants in one study (Varcoe et al., 2012) reported that their moral distress motivated them and enabled them to build resolve. Nursing students experiencing moral distress reported seeing it as a form of learning, to avoid this happening to others in the future (Renno et al., 2018).

| Understanding factors contributing to moral distress among RNs and nursing students
Evidence for the contribution of individual characteristics, including, age, length of service and gender, on moral distress was inconclusive. There is a need for further research to examine whether there are common individual characteristics that exacerbate nurses' experiences of moral distress. Identifying those who are most at risk of experiencing moral distress may enable more effective targeting and tailoring of interventions, as well as crucial learning around factors that might be protective against moral distress, especially among nurses working in similar roles and clinical environments.
This evidence would be vital to inform development of interventions to prevent moral distress rather than mitigating the effects of moral distress that has already occurred and caused harm.
However, studies examining factors contributing to moral distress experiences were mostly correlational and used convenience sampling, which in itself runs the risk of selection bias.
Furthermore, different measures were used to assess moral distress Three studies (Alberto Fruet et al., 2019;Hou et al., 2021;Pergert et al., 2019) used translated versions of the original English language MDS (Corley et al., 2001) and MDS-R (Hamric et al., 2012), two used a version of the MDS adapted for psychiatry (Delfrate et al., 2018;Hamaideh, 2014) and one used Epstein et al.'s (2019) Measure of Moral Distress for Healthcare Professionals which is based on the MDS. However, measures used in the remaining five studies (Haghighinezhad et al., 2019;Krautscheid et al., 2020;Rathert et al., 2016;Robaee et al., 2018;Wands, 2018)  RNs' and nursing students' perceived autonomy, ability to advocate and opportunity to raise concerns around care, were consistently reported to contribute to nurses' experiences of moral distress.
Insufficient institutional support to behave ethically, inadequate resources, insufficient staffing and a wider 'culture of silence' (Pavlish et al., 2016) all precipitated moral distress. Yet, insufficient resources and poor staffing levels were triggered by high levels of moral distress among team members, creating a vicious cycle (Delfrate et al., 2018;Ganz et al., 2013;Harrowing & Mill, 2010;Hsun-Kuei et al., 2018;Silverman et al., 2021). Moral distress was also associated with increased risk of workforce turnover and loss. Experiencing moral distress resulted in as many as a quarter of nurses considering leaving their current role and up to half intending to leave the nursing profession. Prior to the SARS-CoV-2 pandemic, the nursing workforce was already depleted, with a deficit of 6 million nurses globally (World Health Organization, 2020). Shortfalls are predicted to increase (Douglas et al., 2020) due to an ageing international nursing workforce (Denton et al., 2021;Kwok et al., 2016;Ryan et al., 2017). Demand for healthcare is intensifying due to changing patient demographics, widening health inequalities and increasing chronicity. There are serious implications for the quality and safety of care provision and the health and well-being of the nursing workforce. Protecting, sustaining and retaining a healthy, motivated and appropriately supported nursing workforce is central to the delivery of high quality, safe and effective care and meeting current and future population health needs (Gray et al., 2020;World Health Organization, 2021). The risk of further loss of nursing personnel and expertise in the wake of the COVID-19 due to moral distress pandemic places urgency on healthcare organisations and governments internationally to develop national strategies, organisational policies and interventions to mitigate the impact of moral distress on the nursing workforce.
The effects of moral distress on nursing students' own health, well-being and intentions to remain do not appear to have been reported in the literature. Yet interestingly, nursing students responded to their moral distress by seeing it as a form of learning.
They wanted to prevent this happening to others as they developed in their careers (Renno et al., 2018

| Strengths and limitations
Our systematic review was conducted by a multidisciplinary review team with a minimum of two reviewers engaged in the independent screening and extracting process. Some aspects of systematic review methodology were simplified to produce a review in a short enough time frame for the findings to remain relevant as healthcare services shift to the recovery phase of the pandemic. More specifically, searches were limited from 2010 to 2021 and empirical literature focused on nurses published in the English language. It is entirely possible that some potentially useful studies, notably those not published in the English language have been omitted. We also excluded pre-prints and consequently identified only one study focusing on moral distress among nurses in the context of a pandemic. It is highly likely that over time the empirical literature pertaining to moral distress in the context of SARS-CoV-2 will grow. By limiting the search dates in this way we have ensured that the evidence assessed has context and relevance to current policy and practice.

| CON CLUS IONS
This systematic review is important and timely given wider changes in the healthcare landscape and the SARS-CoV-2 pandemic which has substantially increased pressure on nurses and others providing care. This review adds specifically to understanding the effects of moral distress on RNs and nursing students. Several factors contribute to their moral distress experience that may be related to a perceived inability to enact moral agency. Experiences of moral distress are complex, relational and located at individual, team organisational and structural levels. The moral distress experience does not occur in a vacuum and there is potential for the interplay of complex relationships between individuals and organisational structures. Accordingly, moral distress is an inherently relational, complex and contextualised phenomenon. In challenging situations, there was a perception that RNs and nursing students were unable to enact an idealised version of their role.
RNs and nursing students were constrained by personal perceptions of powerlessness, insufficient specialist practice and ethical knowledge, a perceived lack of agency to do the best for patients, and their families, and, at structural levels, relational and organisational constraints. Although encouraged to develop their own resilience, RNs and nursing students may be unable to exercise professional autonomy and uphold patient interests.
Moral distress impacted RNs' health and well-being and manifest in emotional reactions including guilt, self-doubt, loss of selfconfidence, anger and frustration. Health-threatening behaviours were also identified. These emotions and behaviours may have

ACK N O WLE D G E M ENTS
Elizabeth Gillen, specialist librarian for assisting with the search strategy design and searches.

FU N D I N G I N FO R M ATI O N
This work was funded by Public Health Wales. Public Health Wales is an NHS organisation providing professionally independent public health advice and services to protect and improve the health and well-being of the population of Wales. However, the views in this article are entirely those of the authors and should not be assumed to be the same as those of Public Health Wales.

CO N FLI C T O F I NTE R E S T S TATE M E NT
Professor Richard Kyle was employed by Public Health Wales when the review was commissioned.

DATA AVA I L A B I L I T Y S TAT E M E N T
Data available in article supplementary material.

E TH I C S S TATEM ENT
Research Ethics Committee approval was not required for this mixed-methods systematic review.

PATI E NT CO N S E NT
Patient consent was not required for this mixed-methods systematic review.