The definition and typology were developed using a co-design approach as part of a broader project to create a digital mental health care navigation tool for health system planners (MChart) [32]. This approach used a nominal group technique guided by an expert-based cooperative analysis (EbCA) approach. EbCA is a structured participatory methodology that integrates existing evidence with stakeholder and expert knowledge to inform decision-making. Facilitated, iterative discussion conducted either face-to-face or virtually is used to support consensus on key decisions [33]. Development was guided by the TRL-IS, which has been adapted for use in health and social sciences contexts [25]. The TRL-IS incorporates multiple sources of knowledge, including scoping reviews and the combined expertise of the core project team and external subject matter experts. The process of establishing the prior knowledge base using TRL-IS levels involved identifying existing literature, developing reviews, presenting this to the expert panel, and developing the consensus definition and characteristics informed by the prior knowledge base. The process is outlined in Figure 1.

In this context, “expert knowledge” refers to a combination of professional and experiential insights, typically acquired through more than 10,000 hours of practice in a given field [34,35]. Contributions from individuals with lived experience ensures that the co-design process is meaningfully grounded in user-centered perspectives [34]. Expert knowledge was elicited through the nominal group technique, which is especially well suited to problem-solving in emerging fields in which knowledge is still developing, fragmented, or contested [36,37]. The method is widely used for the development of ontologies and typologies in such areas [38].

The core study team consisted of 7 multidisciplinary members, including clinicians (a psychiatrist, a mental health nurse, and an addiction specialist), health policymakers, and academic researchers. This team developed an a priori definition and set of characteristics for digital mental health care navigation tools drawing on recent reviews and studies [10,39]. To refine these preliminary outputs and build consensus, an expert panel was formed and engaged using a nominal group technique.

Participants were invited based on their professional affiliations and relevant expertise. All panel members had experience working within the mental health care system and knowledge of the challenges associated with digital navigation and service access. Invitations were sent via email, and those who accepted were included in the panel. In total, 31 individuals were purposively recruited, with 28 (90.3%) accepting the invitation to participate. The panel included a mental health care consumer and advocate; mental health planning and policy practitioners; and representatives from PHNs, mental health community-managed organizations, health care financing and delivery, and clinicians (including psychiatrists, psychologists, general practitioners, and a nurse health care system navigator). The full list of panel members and their demographics and expertise are provided in Multimedia Appendix 1. The expert panel was chaired by the chief investigator (a psychiatrist and researcher). The panel convenor was a researcher with mental health policy expertise.

Between November 2023 and December 2023, the expert panel convened twice for 2-hour meetings conducted in hybrid format (in person and online via Zoom [Zoom Video Communications]). Consistent with the EbCA approach, 1 week prior to the meetings, background documents and questions were circulated to members to enable preparation and support informed participation. All meetings were recorded and transcribed, with notes and key decisions circulated to panel members for validation and feedback. Each session began with an overview of the expert panel’s purpose followed by a presentation from the core study team of their a priori definition (Multimedia Appendix 2) and characteristics (Multimedia Appendix 3).

The following questions were posed to the expert panel: (1) “Do you agree with the proposed definition of a digital mental health care navigation tool?” (2) “Do you agree with the identified characteristics and domains of digital mental health care navigation tools?” (3) “Do you agree with the proposed characteristics, domains and subdomains of digital mental health care navigation tools?”

In line with the EbCA approach, the nominal groups used a structured, iterative method for consensus building. Participants were provided with a synthesis of relevant evidence and a set of guiding questions to support informed, individual reflection. During facilitated discussion, participants shared, discussed, and refined their perspectives through collective deliberation, integrating the evidence with experiential knowledge. Discussions were recorded and synthesized into meeting notes by the study team, with iterative updates to the definition, domains, and characteristics circulated to participants between meetings. Particular attention was paid to the contributions from panel members representing consumer and carer organizations, ensuring that their perspectives were meaningfully incorporated into the consensus process.

On the basis of panel input, the core study team revised the definition and characteristics, which were then circulated for further feedback to refine the consensus definition and typology. Panel members provided feedback either during meetings or individually via email if they preferred. Discussions focused on mental health care provision for individuals with mental health conditions. Topics related to general public information provision, prevention, and mental health interventions were excluded from the scope.

The study protocol was reviewed and approved by the Australian Capital Territory (ACT) Health Human Research Ethics Committee (2023.ETH.00112). Participants were provided with an information sheet and were asked to complete and sign a consent form and a conflict-of-interest declaration prior to their participation in the expert panels. Consistent with the nominal group technique, a conflict of interest did not preclude inclusion in the expert panels. Declared conflicts included employment in organizations involved in mental health service planning in the ACT (2/28, 7.1%) and employment in an organization that contributed funding for the project (1/28, 3.6%). All data reported in public outputs, including reports and publications, were deidentified. Panel members were not compensated for their time, with the exception of the lived experience consumer representative, who received an honorarium for their contribution.

The study protocol was not prospectively registered. The methodology was guided by the ACCORD (Accurate Consensus Reporting Document) reporting template for consensus-based methods, and the checklist is provided in Multimedia Appendix 4 [40].

The study team presented their draft definition of digital mental health care navigation tools to the expert panel, who were invited to respond to the guiding questions outlined earlier. This discussion generated several key considerations, including clarification of the term “individuals,” the relationship between digital navigation tools and mental health interventions, and the intended purpose of these tools. Panel members emphasized the importance of using nonmedicalized language and debated whether health promotion and prevention should be included as components of mental health care. Following these discussions, the study team revised the definition in collaboration with the panel. The co-designed definition, shown in Textbox 1, identifies the primary function of digital mental health care navigation tools as supporting various users in locating appropriate mental health care services and professionals. The key characteristic of a digital mental health care navigation system is that it provides accessible, service-specific information to facilitate digital mental health care navigation.

To our knowledge, this is the first definition and typology of digital mental health care navigation tools. Despite the growing number of digital mental health care navigation tools in Australia and internationally, there remains a limited body of peer-reviewed literature addressing their formal definition, structure, and quality. This study contributes to this rapidly emerging and important field by developing a co-designed definition and typology of characteristics for digital mental health care navigation tools.

The comprehensive and structured approach used in this study is well suited to the task of developing foundational knowledge. The use of the nominal group technique proved to be a viable and acceptable method for achieving consensus. This is consistent with its application in other health-related domains, including brain injury case management, clinical interventions, education and training, practice development, clinical measures, and health care research [41-43].

A key contribution of this study is the development of a shared language for digital mental health care navigation tools. Establishing a common vocabulary can help reduce ambiguity (where terms are interpreted in different ways) and vagueness (where definitions lack specificity) [44]. This is particularly important due to inconsistency in currently used terminology. For example, individuals interacting with mental health care services may be described as “clients,” “customers,” “consumers,” “users,” “patients,” or “carers.” Similarly, workforce personnel may be referred to as “support workers,” “recovery workers,” or “case workers”—raising questions about whether these roles provide similar types of support. Comparable issues arise in the way in which services and systems are described, reflecting broader challenges with terminology in health systems research [45,46]. Without greater conceptual clarity, it is difficult to assess and compare the quality, purpose, or functionality of digital mental health care tools.

Lack of consensus in naming has far-reaching implications across clinical, administrative, research, and policy contexts, including information provision, screening, or clinical interventions [45]. Clinicians and help seekers may use and interpret names differently. Lack of agreement can result in inconsistent service delivery as terms may be applied differently, leading to variability in access. These challenges highlight the need to develop a glossary of terms to clarify and explain the components of digital mental health care navigation tools.

The typology developed in this study lays the groundwork for the quality assessment of digital mental health care navigation tools. However, the absence of standardized definitions and quality criteria currently limits the ability to evaluate their reliability, accuracy, and ethical design. While the National Safety and Quality Digital Mental Health Standards [17] provide voluntary guidance for digital mental health services, they do not explicitly include criteria for digital navigation tools. The standards recommend that service providers implement quality improvement systems, but they do not define what constitutes quality or accuracy in the context of information provision [10]. The need for tailored quality assessment mechanisms to digital mental health care navigation tools was emphasized by the expert panel.

This study is the first to develop a co-designed definition of digital mental health care navigation tools and identify their characteristics through a structured expert consensus process. By engaging a diverse panel of stakeholders with expertise in mental health policy, service delivery, research, clinical practice, and lived experience, this study strengthens the relevance and applicability of its findings across contexts [35].

The involvement of expert knowledge in defining and characterizing complex constructs has been shown to enhance the rigor and utility of scientific knowledge development [35]. The resulting definition and typology have the potential to inform the development, evaluation, planning, funding, and quality assessment of digital mental health care navigation tools and digital navigation tools more generally. For policymakers and planners, these outputs offer the foundation for a more precise categorization of tools, clearer understanding of service gaps and overlaps, and use of more consistent terminology within the digital mental health care ecosystem.

Panel members’ individual perspectives, experiences, or professional affiliations may have influenced group deliberations. However, this was balanced with the careful and purposeful consideration of the composition of the panel to include diverse perspectives and expertise, including representation from government, clinical care, community services, and lived experience. Furthermore, consistent with nominal group protocols, the group discussion was facilitated such that all opinions were heard, and there was a process of openly reaching a consensus through rounds of discussion within the group. Conflict-of-interest declarations were also collected.

While the nominal group–informed expert panel provides valuable insights from experts, it is important to acknowledge that the perspectives gathered may not be fully representative of the broader community of mental health care policymakers and practitioners. Transparent reporting of the panel’s compositing and expertise improves reproducibility and credibility [47]. The panel included a high percentage of panelists from the ACT as this was the pilot area and local knowledge is critical for the tool’s assessment and validation. Experts from 4 states and territories participated, and as the ACT is the capital of Australia and the location of headquarters of governmental agencies, many participants had previous or current experience working in other states as well as in national organizations. The expert panel included 1 consumer representative with unique experience in digital health, having been a deputy chair of the National Safety and Quality Digital Mental Health Standards committee. In addition, 2 expert panel members represented national organizations and peak bodies of mental health care providers and consumers.

Future work is needed to evaluate the generalizability, usability, and adoption of the proposed definition and typology characteristics of digital mental health care navigation tools in diverse contexts. Our previous development of taxonomies for mental health services (Description and Evaluation of Services and Directories [48], a brain injury case management taxonomy [42], and the Global Impact Analytics Framework [27]) illustrate how taxonomies can be generalized to other fields. The Description and Evaluation of Services and Directories has been extended to drug and alcohol, aging, disability, and Indigenous health and neurology and has been used in 35 countries. The brain injury case management taxonomy has been used in disability and chronic care [42], and the Global Impact Analytics Framework has been used in impact analysis of digital mental health interventions for veterans and first responders [49] and for First Nations social and emotional well-being [50]. It would also be important to run an analysis of digital mental health care navigation tools using this definition to delineate between digital navigation tools and those that are not navigation tools, such as those limited to information provision, clinical assessment, or interventions. To improve generalizability, in the future, it would be important to develop a related glossary of terms to further support consistent use.

The consensus on digital mental health care navigation tool characteristics is critical for the development of quality indicators to allow for systematic assessment and benchmarking. While the definition and typology developed in this study have potential applicability beyond Australia and across health systems more broadly, it is important to consider the extent to which specific elements may be shaped by the Australian policy and service context. For example, features related to system navigation, service categorization, and referral pathways are influenced by the structure of Australia’s mixed public-private health care system, the role of federally funded digital mental health services, and the presence of national initiatives such as Medicare Mental Health. In health systems with different funding arrangements, levels of service integration, or digital infrastructure, these elements may require adaptation. At the same time, several core components of the typology—such as the distinction among navigation, information provision, assessment, and intervention functions; the emphasis on user-centered design; and the role of navigation tools in addressing fragmentation—are likely to be transferrable across contexts. These features reflect common challenges in mental health systems internationally, including complexity, fragmentation, and barriers to access [51,52].

Given that digital mental health tools are implemented across diverse systems with varying infrastructure and governance arrangements [53,54], future research should focus on assessing external validity and applicability across settings, including through cross-country consensus approaches [38,55]. Such work would help distinguish context-specific versus universal elements and support the development of a globally relevant framework for digital mental health care navigation tools.

Digital mental health care navigation tools play a significant role in addressing persistent challenges in Australia’s mental health system, particularly fragmentation, delayed access to care, and unmet needs. The rapid proliferation of digital mental health care navigation tools reflects a growing momentum across sectors to invest in digital infrastructure that helps people connect with services more efficiently. However, the rapid rollout of these tools in the absence of shared definitions, standards, or quality frameworks risks further entrenching the very fragmentation they are intended to resolve. Without clear boundaries regarding purpose, audience, and functionality, digital mental health care navigation tools may become inconsistent in design and messaging, potentially leading to confusion for users and reduced effectiveness overall. Over time, such inconsistency may undermine trust and diminish the perceived value of digital mental health care navigation tools as important infrastructure for mental health reform.

This study directly addresses that risk by offering a co-designed definition and typology of characteristics of digital mental health care navigation tools. These foundational elements provide a starting point for greater coherence, comparability, and accountability in the development and evaluation of such tools. They also enable a more consistent language for policy and planning, which is essential for system-level coordination.

For policymakers, health system managers, and funders, these findings underscore the need to establish quality standards and oversight mechanisms specific to digital mental health care navigation tools. These standards should include guidance on terminology, data integrity, ethical design, accessibility, and transparency of service information. Without such measures, digital tools risk becoming fragmented solutions within a fractured system. Ultimately, effective digital mental health care navigation tools must do more than provide information; they must support individuals, families, carers and kin, and communities in making sense of a complex and often overwhelming system. When designed with clarity, care, and accountability, digital mental health care navigation tools can play a transformative role in improving access, equity, and mental health care outcomes across Australia and internationally.