Frontline workers, including health care professionals, emergency service personnel, police officers, firefighters, and humanitarian responders, are routinely exposed to traumatic and highly stressful events as part of their occupational roles [1]. These exposures include repeated encounters with serious injury, death, violence, and human suffering, often under conditions of sustained workload pressure, moral complexity, and limited opportunity for recovery. The psychological consequences are well established and include posttraumatic stress disorder (PTSD), depression, burnout, moral injury, and increased risk of suicidality [2,3]. However, trauma rarely remains confined to the individual worker [4]. Growing evidence indicates that occupational stress and trauma exposure among frontline workers can have significant ripple effects across family systems, affecting the psychological well-being, relationships, and daily functioning of spouses, partners, and children [5,6]. Partners may experience secondary traumatic stress, emotional exhaustion, relationship strain, and increased caregiving responsibilities, whereas children may be affected through reduced parental availability, emotional withdrawal, disrupted parenting practices, and the intergenerational transmission of stress-related coping patterns [7-9].

Qualitative research has further illuminated these relational impacts. An interpretative phenomenological analysis of partners of veterans with mental health difficulties identified sustained caregiving, emotional containment, and advocacy as central features of partners’ experiences, illustrating how trauma shaped everyday relationships and family life [10]. Although conducted in a military context, these findings offer insights relevant to civilian frontline families. Civilian evidence has since strengthened this picture: a systematic review by Tekin et al [11] found that occupational stress among health care workers was associated with adverse psychological outcomes and poorer family functioning, including impaired communication, disrupted social life, and increased household burden, while a UK mixed methods study reported clinically significant levels of secondary traumatic stress among household members of health care workers, particularly spouses and partners [12]. Qualitative work has similarly shown that duty-related trauma becomes embedded in everyday family life, shaping communication, emotional availability, and shared understandings of “normal” family functioning [13]. Collectively, these findings confirm that the family-level impact of frontline occupational trauma is an increasingly important area of research and intervention development [14,15], extending beyond military populations into civilian health care and emergency service settings.

Despite this growing recognition, the evidence remains fragmented across disciplines, including occupational health, nursing, psychiatry, psychology, and family studies, and is characterized by substantial heterogeneity in study populations, frontline occupations, conceptual frameworks, methodologies, and outcomes. This fragmentation makes it difficult to establish which family outcomes are most consistently reported and where the evidence base remains thin, limiting the development of cumulative knowledge and the translation of evidence into family-inclusive policy, practice, and service design.

Existing reviews offer valuable but partial syntheses. Casas and Benuto [16] examined traumatic stress spillover among first responder families but were limited to 16 studies published through 2020, focused primarily on spouses of police, fire, and emergency medical personnel, and relied predominantly on cross-sectional evidence. May et al [4] synthesized qualitative evidence on family members of emergency first responders with diagnosed or probable PTSD, identifying themes of role change, secondary and vicarious trauma, child impacts, and unmet support needs, but were restricted to qualitative studies and a PTSD-specific sample. Neither review captures the broader, rapidly expanding evidence base across diverse civilian frontline occupations, trauma conceptualizations beyond PTSD, multiple methodological approaches, or postpandemic research, and no existing synthesis systematically examines how family impacts have been conceptualized and measured across sociocultural contexts.

A scoping review is therefore warranted to systematically map and synthesize the existing evidence on family outcomes associated with frontline workers’ occupational trauma. By integrating qualitative, quantitative, and mixed methods research across diverse civilian frontline occupations, this review will clarify the breadth and characteristics of the evidence base, examine how family impacts have been conceptualized and measured, identify knowledge gaps across populations and contexts, and inform future research, policy, and the development of family-inclusive, trauma-informed services and interventions [17].

The primary question of the scoping review is as follows:

The secondary questions of the scoping review are as follows:

This scoping review will be conducted in accordance with the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) [18] and the Joanna Briggs Institute (JBI) methodological framework and will be informed by best-practice guidance for evidence synthesis [19]. Additionally, the conduct and reporting of the review will be guided by the evidence-based checklist for improving the quality of scoping reviews [20], which provides practical recommendations to enhance methodological transparency, consistency, and reporting standards. The PRISMA-ScR checklist is provided in Checklist 1.

This scoping review synthesizes evidence from previously published sources and does not involve primary data collection with human participants; therefore, formal ethical approval was not required.

Consistent with JBI guidance for scoping reviews, informal stakeholder consultations were undertaken between January and March 2026 to enhance the relevance, scope, and applicability of the review [21]. In total, 6 stakeholders participated in the consultation process, comprising 3 frontline workers from civilian frontline occupations and 3 family members of frontline workers with lived experience of the family impacts of occupational trauma. Participants were purposively identified through the authors’ professional networks and existing academic and clinical collaborations because of their relevant professional or lived experience.

The consultation process comprised 6 individual online discussions conducted via Microsoft Teams, each lasting approximately 30 to 60 minutes. Discussions focused on the relevance of the proposed review, the clarity and scope of the review questions, the appropriateness of the population, concept, and context (PCC) framework, terminology relating to frontline occupational trauma and family outcomes, and perceived gaps within the existing literature. Participants also highlighted family outcomes they considered particularly important, including psychological well-being, relationship functioning, family communication, caregiving burden, secondary traumatic stress, parenting, and broader family functioning. Feedback from these consultations informed the refinement of the review questions, eligibility criteria, the PCC framework, the preliminary search strategy, and the data-charting framework (Table 1). The consultations also contributed to refining the conceptualization of family outcomes and to ensuring that the protocol addressed issues considered meaningful and relevant to frontline workers and their families.

The consultations were undertaken solely to inform protocol development and did not form part of the research data included within the scoping review. No interviews or focus groups were conducted for research purposes, no audio recordings or transcripts were produced, no identifiable participant information was collected or retained, and no data were systematically analyzed or reported. Consequently, formal ethical approval was not required.

The search strategy will be developed and conducted in accordance with the JBI methodological guidance for scoping reviews and will be reported in accordance with the PRISMA-ScR and relevant elements of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Literature Search Extension (PRISMA-S) guidance to enhance transparency and reproducibility of the search process [18,22].

Protocol development commenced in December 2025 and included preliminary exploratory searches undertaken in CINAHL and PsycINFO to identify relevant keywords, index terms, and subject headings related to frontline worker populations, occupational trauma and stress exposure, and family members. The search strategy was subsequently refined through iterative discussion within the research team, consultation with an academic librarian with expertise in systematic and scoping review methodology, and stakeholder consultation undertaken between January and March 2026. These activities were undertaken to optimize the sensitivity, specificity, and comprehensiveness of the final search strategy. The final search strategy combines three core concepts:

Comprehensive electronic database searches will be undertaken following publication of this protocol in PubMed (MEDLINE), PsycINFO, CINAHL, Web of Science, and Scopus. Searches will be conducted from database inception to the final search date. No publication date restrictions will be applied. Searches will be limited to studies published in English. Both controlled vocabulary terms (eg, MeSH and database-specific subject headings) and free-text keywords will be used where appropriate. Boolean operators (AND and OR), truncation, phrase searching, field-specific searching, and database-specific syntax will be applied to maximize search sensitivity and reproducibility.

To enhance transparency and reproducibility, the complete search strategy for PubMed (MEDLINE) is provided in Multimedia Appendix 1. The PubMed (MEDLINE) search strategy serves as the reference strategy for the review and will be adapted for PsycINFO, CINAHL, Web of Science Core Collection, and Scopus using each database’s controlled vocabulary, indexing terms, and search syntax while maintaining conceptual equivalence across the 3 core search concepts.

All retrieved records will be imported into reference management software, and duplicates will be removed. Title and abstract screening will be followed by full-text screening of potentially eligible studies. Screening will be undertaken independently by at least 2 reviewers, with discrepancies resolved through discussion or consultation with a third reviewer where necessary. Reference management will be conducted using EndNote (Clarivate), and screening will be managed using Rayyan. The study selection process will be documented using a PRISMA-ScR flow diagram.

Data will be extracted using a structured charting form developed specifically for this review and informed by the PCC framework and the review questions, consistent with established scoping review methodology [21,23,24]. The charting form will capture bibliographic information (author, year of publication, and country), study aims, study design and methodology, and participant characteristics, including family member type, age, and relationship to the frontline worker.

Data extraction will also include details relating to the frontline worker population, occupational setting, the type and nature of trauma or occupational stress exposure, and the conceptualization and measurement of family outcomes, including psychological, relational, social, behavioral, and family functioning outcomes. Information relating to theoretical or conceptual frameworks, key findings, implications for policy, practice, and service development, and identified research gaps and study limitations will also be extracted.

The data charting form will be piloted using a small sample of included studies to ensure clarity, consistency, and completeness before full data extraction commences [21,24]. Modifications to the charting form will be documented where necessary to improve data capture during the review process. Data extraction will be undertaken independently by 2 reviewers for a proportion of included studies to promote consistency, with disagreements resolved through discussion and, where required, consultation with a third reviewer. Extracted data will subsequently undergo descriptive numerical analysis, narrative synthesis, and evidence mapping, as described in the Data Synthesis section.

Consistent with the JBI methodological guidance for scoping reviews and the PRISMA-ScR, no formal critical appraisal of methodological quality or risk of bias will be undertaken [18,21]. The purpose of this scoping review is to systematically map the extent, characteristics, and nature of the existing evidence on the impacts of frontline workers’ occupational trauma on family members rather than evaluate the methodological quality or effectiveness of individual studies.

Data synthesis will be undertaken in accordance with the JBI methodology for scoping reviews [21]. Findings will be synthesized using descriptive numerical analysis, narrative synthesis, and evidence mapping. Descriptive numerical analysis will summarize study characteristics, including publication year, country of origin, frontline occupation, study design, participant characteristics, family member type, trauma exposure, family outcomes, and methodological approach. Results will be presented in summary tables and descriptive figures. Narrative synthesis will integrate qualitative, quantitative, and mixed methods evidence to examine how family outcomes associated with frontline workers’ occupational trauma have been conceptualized, measured, and reported across occupational groups and sociocultural contexts. The synthesis will be structured around the review objectives, focusing on psychological, relational, social, behavioral, and family functioning outcomes. Evidence mapping will visually summarize the distribution of the literature across frontline occupations, family member groups, geographical settings, study designs, trauma-related concepts, and reported family outcomes. This will highlight areas where evidence is well established and identify important gaps. Evidence gaps relating to underrepresented populations, occupational groups, family member roles, geographical regions, methodological approaches, and outcome domains will be identified to inform future research, policy, practice, and the development of family-inclusive, trauma-informed services. Findings will be reported through narrative summaries, summary tables, and evidence maps in accordance with the JBI methodology [21] and PRISMA-ScR guidance [18].

Any deviations from this protocol will be documented, justified, and reported in the final scoping review.

Protocol development was undertaken between December 2025 and July 2026, including preliminary scoping searches, refinement of the PCC framework, development of the search strategy, stakeholder consultation, and piloting of the data-charting framework. Preliminary exploratory searches conducted in CINAHL and PsycINFO in December 2025 retrieved 557 records, of which 17 studies were identified as broadly relevant and used to refine the review’s scope, eligibility criteria, and search strategy; these preliminary findings do not constitute the results of the completed scoping review. No specific external funding was received for this review. As this is a scoping review, participant recruitment is not applicable. Comprehensive database searches, study screening, data charting, and evidence synthesis have not yet commenced and are projected to begin in August 2026, with data charting and evidence synthesis undertaken between September and October 2026. At the time of protocol submission, formal data analysis had not commenced. Completion of the review is anticipated by November 2026, with findings disseminated through peer-reviewed publication and conference presentations by the end of 2026.

Following publication of this protocol, eligible studies will then undergo title and abstract screening, full-text review, data charting, and narrative synthesis. The completed review will map the characteristics and distribution of the evidence base, identify knowledge gaps across occupations and sociocultural contexts, and inform recommendations for future research, policy, and the development of family-inclusive, trauma-informed interventions.

The dissemination strategy will be multifaceted, targeting academic, professional, policy, and public audiences with an interest in frontline well-being, occupational trauma, and family mental health, consistent with established knowledge translation frameworks [25,26]. Findings will be submitted to a peer-reviewed, open-access journal and reported in accordance with PRISMA-ScR [18], ensuring transparent reporting of the search strategy, study selection, data charting, and synthesis methods. Results will also be shared through poster and oral presentations at national and international conferences spanning psychology, occupational health, and trauma to reach researchers, clinicians, service leaders, and policymakers. Beyond academic channels, dissemination will include accessible evidence summaries and stakeholder briefings for frontline workers, family members, and frontline organizations to support practical interpretation of the findings. The review will also inform future research priorities and the development of family-inclusive, trauma-informed interventions, services, and policies [27].

This scoping review is expected to provide the first comprehensive map of evidence on family outcomes associated with occupational trauma exposure among civilian frontline workers. Based on preliminary scoping searches and the existing literature, family members are anticipated to report a broad range of adverse outcomes, including psychological effects such as secondary traumatic stress, anxiety, and depression; relational difficulties such as marital strain, disrupted communication, and family conflict; and broader social consequences, including increased household burden, role strain, and social withdrawal [28-30]. The review is also expected to show that the extent, consistency, and distribution of these outcomes vary considerably across frontline occupations, family roles, and sociocultural contexts and that this variation has not yet been systematically mapped. By identifying patterns within the existing evidence and highlighting areas in which evidence remains limited or absent, this review is expected to provide an important foundation for future research, policy development, and the advancement of family-inclusive, trauma-informed services and interventions. Two existing reviews have examined related questions but leave important gaps that this review is designed to address. Casas and Benuto [16] examined traumatic stress spillover among first responder families but were limited to 16 studies published through 2020 and focused primarily on spouses of police, fire, and emergency medical personnel using predominantly cross-sectional evidence. May et al [4] synthesized qualitative evidence on family members of emergency first responders with diagnosed or probable PTSD, identifying themes of role change, secondary and vicarious trauma, child impacts, and unmet support needs, but were restricted to qualitative studies and a PTSD-specific sample. More recent single-occupation studies, including the systematic review conducted by Tekin et al [11,12] and UK mixed methods survey of health care workers’ families, point to a rapidly expanding postpandemic evidence base that neither earlier review could capture. By integrating qualitative, quantitative, and mixed methods studies across diverse civilian frontline occupations, trauma conceptualizations beyond PTSD, and evidence published since the COVID-19 pandemic, the present review is positioned to substantially extend and update this earlier work rather than duplicate it.

This review has several strengths. It will be conducted using a rigorous and transparent methodology consistent with the JBI framework for scoping reviews and reported in accordance with the PRISMA-ScR. The inclusion of qualitative, quantitative, and mixed methods studies will enable a more comprehensive synthesis than prior single-design reviews, and the use of evidence mapping alongside narrative synthesis will allow gaps to be identified systematically rather than descriptively.

Several limitations are also anticipated. The review will be restricted to English-language publications, which may exclude relevant non-English literature, although evidence suggests this is unlikely to systematically bias the conclusions. Consistent with scoping review methodology, no formal quality appraisal will be undertaken, meaning the review will map the extent and nature of the evidence rather than its methodological strength. Restricting inclusion to studies in which family members are the primary focus may exclude relevant findings reported as secondary outcomes within worker-focused research, a limitation partially mitigated through reference list screening. Families of military personnel will be excluded to preserve conceptual coherence with civilian frontline contexts, meaning findings may not generalize to military family populations. Finally, the stakeholder consultations informing this protocol were exploratory and involved a small, purposively identified sample; they were not intended as, and should not be interpreted as, formal qualitative research.

The review will help identify priorities for future research, including the need for longitudinal studies, greater inclusion of children and other underrepresented family members, and improved consideration of sociocultural and contextual influences on family outcomes. From a policy and practice perspective, the findings will support the development of family-inclusive, trauma-informed approaches within frontline organizations by highlighting the importance of recognizing families as integral to the broader system affected by occupational trauma. Ultimately, this review is expected to strengthen the evidence base for understanding how frontline workers’ occupational trauma affects family members, while informing future research, guiding policy and service development, and supporting the implementation of family-inclusive, trauma-informed approaches across civilian frontline sectors.