Horizon scanning refers to the structured identification and analysis of weak signals, trends, drivers of change, wild cards, and discontinuities, enabling anticipation of future developments [1]. It belongs to the broader field of futures studies, which is concerned with exploring, modeling, and preparing for alternative future scenarios. Although horizon scanning has been widely adopted across diverse sectors, its application in the medical sciences is relatively recent [2]. The National Institute for Health and Care Research (NIHR) Innovation Observatory uses horizon scanning to systematically detect weak signals and trends of innovative health care technologies and support future decision-making processes about them [3].

Unlike evidence synthesis, understood as the process of systematically identifying, appraising, and integrating findings from multiple studies on a specific topic to generate comprehensive, reliable, and policy- or practice-relevant conclusions [4], horizon scanning focuses on the systematic process of detecting and collecting early signs and weak signals of potentially important developments that, in this context, may be interpreted as innovative health care technologies [5]. However, horizon scanning currently lacks standardized reporting guidance, particularly for key aspects of the horizon scanning process such as the identification, selection, and prioritization of emerging health technologies. Furthermore, a recent review of horizon scanning practices in medical technologies, diagnostics, and digital health recommended the use of dedicated reporting standards in light of the inconsistent use of terminology in the field [6]. This lack of clarity impedes the dissemination and utility of horizon scanning outputs—such as published reports and research articles—and contributes to research inefficiencies, including duplication and underuse of findings [7].

Horizon scanning is more likely to be used to widely explore the “unknowns,” being those more or less certain and definitively less defined, on emerging areas of innovation across diverse domains. Using the Rumsfeld matrix as a conceptual framework and using it to compare horizon scanning with other well-established methodologies such as evidence synthesis, we could argue that, while evidence synthesis is akin to examining the visible tip of an iceberg (“known knowns”), horizon scanning focuses on what lies beneath the surface (“unknown knowns” and “known unknowns”) [8].

While horizon scanning is recognized as a methodological approach in its own right, it requires clear principles and structured processes to ensure rigor and consistency. Despite its growing use in health and policy contexts, the field remains underserved by methodological frameworks, reporting standards, or dedicated guidance. This absence of consensus risks limiting the transparency, comparability, and overall impact of horizon scanning outputs. Reporting guidelines specify a minimum set of elements that should be included in research publications and have been shown to enhance methodological transparency and promote the use of research findings [9]. To our knowledge, no standard reporting guidelines currently exist to support the transparent and consistent documentation of horizon scanning activities in the health care domain. Given the increasing role of horizon scanning in health care decision-making—both in the United Kingdom and internationally—this study aimed to address this gap by developing the first reporting checklist for horizon scanning methods in medical innovation.

This study aimed to initiate the standardization of reporting practices for horizon scanning methods and tools, thereby enhancing the transparency and reproducibility of such approaches.

Our objectives included the development of a conceptual framework for horizon scanning research question formulation and query translation and the development of a preliminary checklist specifying essential and optional elements that should be transparently reported in horizon scanning outputs and a glossary to support consistent interpretation and reduce ambiguity in terminology. Further work will support finalization of the checklist, incorporating the experience of those who used this preliminary version.

This checklist is intended for application to horizon scanning outputs, including both articles published in academic journals and reports published on institutional websites. The checklist is developed to provide detailed and transparent information about the application of horizon scanning methods to medical health technologies. Intended users of this checklist include authors of such reports, peer reviewers of manuscripts submitted to journals for publication, and journal editors when assessing such manuscripts and methods.

A working group consisting of 4 horizon scanning specialists, 2 evidence synthesis specialists, and 2 information specialists was convened at the NIHR Innovation Observatory in May 2024. Participants were selected based on demonstrable expertise in horizon scanning, evidence synthesis methodology, and information science. Their disciplinary backgrounds spanned medical sciences, biosciences, and information science, and their professional experience included conducting systematic reviews, advanced information retrieval, and horizon scanning across medicines, medical devices, diagnostics, and digital health technologies. The group reflected methodological and professional diversity, encompassing varied levels of seniority and experience working on projects for multiple stakeholder groups. All members had established publication records in relevant methodological or applied domains, providing evidence of recognized subject matter expertise.

Four structured workshops, each lasting approximately 2 hours, were conducted between May 2024 and October 2024 to define objectives, iteratively refine methodological components, and develop the checklist. Prior to these sessions, an initial planning meeting was held in which the group established the study aims, scope, procedural approach, and decision-making processes that would guide the workshop series. During the workshops, proposed items and revisions were discussed collectively, and decisions were reached through structured deliberation, with agreement determined either through consensus where possible or, when consensus was not achievable, through majority agreement informed by methodological rationale and supporting evidence from the literature.

Given the similarity of broad scoping reviews with horizon scanning methods, we decided to use the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) as a framework to develop a checklist for reporting items relevant to horizon scanning reports [9]. During the first and second workshops, the group assessed the relevance of each PRISMA-ScR checklist item against the methodological and topic characteristics of horizon scanning reports and produced a modified checklist prototype for horizon scanning studies.

For the internal validation of the prototype, we applied the checklist to outputs produced by the Innovation Observatory between 2017 and 2024. Each team member in the working group was assigned a set of randomly selected reports to screen for suitability and, if applicable, score those reports that used horizon scanning methods for the identification of innovative health care technologies against our checklist prototype. Following the screening process, 17 reports were deemed suitable for scoring. The rest were excluded as they were not horizon scanning reports. Each checklist item was marked as “yes” (included), “no” (not included), or not applicable (“N/A”) if the item was not relevant to that specific paper. Following completion of the scoring exercise, one team member (MF) combined the scores for each item and calculated a final percentage score by dividing the score by the maximum possible score (“N/A” items were not included in the maximum score).

In the third and fourth workshops, the working group reviewed the scores, proposed additional customization of items to address issues relevant to horizon scanning based on the scoring exercise, and achieved consensus on whether the items should be made mandatory or optional. The resulting checklist prototype was uploaded to the Open Science Framework for dissemination.

This study did not involve human participants, patient data, or identifiable personal information. The work consisted solely of methodological development activities conducted by professionals in their occupational roles and analysis of publicly available institutional reports. According to institutional and national research governance guidance, this type of study does not constitute human subjects research and therefore did not require review or approval by an institutional review board or research ethics committee [10].

All procedures were conducted in accordance with applicable institutional, national, and international standards for research integrity and publication ethics [11].

A total of 46 outputs published between 2017 and 2024 were downloaded from the NIHR Innovation Observatory website by a team member (Oleta Williams). In total, 37.0% (n=17) of the horizon scanning reports met the criteria for inclusion in this assessment and were assessed against the checklist. The remaining reports were not horizon scanning reports and were not suitable for this assessment. The reasons for exclusion were being only an abstract, a methods paper, or a presentation (not a report). Figure 1 presents the PRISMA flowchart for the identification of studies.

A total of 42.9% (15/35) of the items achieved a final score between 50% and 100%, whereas 57.1% (20/35) of the items scored under 50%. Table 1 presents a breakdown of these items by their total final score.

Next, based on the working group members’ experience, and in line with the objectives of this study, the items were rated through agreement as optional or mandatory. An optional item meant that the information required was not always possible to disclose due to a number of reasons that include technology stage of development, stakeholder agreements, availability of the information, or relevancy of the item in the context of the horizon scanning scope. These items start with an “If appropriate” statement to indicate their optionality. A mandatory item was deemed of the utmost importance for the conduct of horizon scanning methods and interpretation of results. These needed to be present at all times to achieve transparency in the retrieval and filtration of the signals and replicability of methods, avoid bias in the results, and achieve accountability and impact and overall increased rigor in the final horizon scanning output.

The resulting checklist contains 35 items (n=31, 88.6% single items and n=4, 11.4% that include multiple subitems), of which 28 (80%) were deemed mandatory and 7 (20%) were deemed optional (items 15, 16, 17b, 19, 20, 21, and 23). Some subsections, such as “Synthesis methods” (items 14a and 14b) in the “Methods” section and “Weak signal selection” (items 17a and 17b) in the “Results” section, present more than 1 item per section, with only item 17b considered optional. The sections “Discussion” (items 24a to 24d) and “Registration and protocol” (items 25a to 25c) also include multiple subitems and are all considered mandatory.

This checklist includes 4 new essential components not found in the PRISMA-ScR checklist. These are “Interest holder description” item 4 in the “Introduction” section; “Scope” item 6 in the “Methods” section; “Technology characteristics” item 19 in the “Results” section; and the introduction of the political, economic, social, technological, legal, environmental, and demographic factors (PESTLED) framework in item 24a in the “Discussion” section.

In the context of health technology horizon scanning, an interest holder (often called a stakeholder) refers to any individual, group, or organization that has an interest in or may be affected by the development, adoption, use, or regulation of a health technology.

Key types of interest holders in this context may be the following:

Interest holders contribute by identifying unmet needs and emerging technologies, understanding key eligibility criteria based on needs or gaps, informing prioritization criteria, providing early feedback on clinical relevance and implementation barriers, and supporting evidence appraisal and decision-making. Their involvement ensures that the scanning process is contextually relevant, anticipatory, and aligned with real-world health system priorities.

To support interpretability and decision relevance, horizon scanning reports should explicitly describe the contextual parameters that shape the scan, including its purpose, decision setting, intended users, policy or clinical domain, and analytic perspective. This is the purpose of applying the horizon, innovation, population, data source, and interest holder (HIP-D/I) scoping framework, which provides a structured approach to define the scope of horizon scanning projects targeting innovative health care technologies through the following 5 key dimensions. Clear specification of these elements enables readers to understand how signals were identified, interpreted, and prioritized and supports appropriate comparison across horizon scanning outputs:

Together, these 5 dimensions support a systematic scoping process that enables transparent and reproducible methods for the identification and prioritization of transformative health technologies.

In horizon scanning studies of health care innovation, providing a detailed description of the identified, filtered, and prioritized technologies is essential to ensure that outputs are meaningful and actionable for decision-makers. Unlike systematic reviews—where the unit of analysis is typically the study and its outcomes—horizon scanning primarily focuses on the identification of innovative technologies and often uses the technology and its characteristics (eg, trial phase or technology readiness levels) as the primary unit of interest. Detailed technology descriptions capture critical attributes such as intended use, mechanism of action, stage of development, anticipated benefits, implementation challenges, and potential impact on health systems.

This level of detail serves several purposes: it supports informed prioritization, facilitates future assessments (eg, HTA or regulatory review), enhances transparency and reproducibility, and enables strategic planning for health system readiness.

To align with these goals, the reporting checklist was adapted to shift the focus from evidence appraisal, as seen in the PRISMA-ScR checklist, to the detection of weak signals, in keeping with the purpose and definition of horizon scanning [12]. Table 2 presents the prototype checklist, including item descriptions and corresponding document sections.

Incorporating the PESTLED framework into the discussion section of a horizon scan on emerging health care technologies enriches the report by situating innovations within a structured macroenvironmental context, thereby highlighting how regulatory dynamics, economic constraints, social and demographic values, and environmental considerations intersect with technological development and diffusion. For instance, a strategic environmental scan of Iranian public hospitals demonstrated that PESTLED-guided analysis enabled the identification of external pressures, including economic sanctions, shifts in disease patterns, and governance issues, which informed adaptive strategies for equitable resource allocation and service delivery [13]. Similarly, scoping reviews applying PESTLED-type analysis to electronic health record implementation revealed how political, economic, sociocultural, and legal dimensions shape adoption trajectories and reveal implementation challenges in low- and middle-income settings [14]. By framing horizon scan findings within the 7 domains of this framework, authors can present a reproducible and comparative analytic lens that directly links emerging technologies to broader system drivers; aids in anticipating barriers to and enablers of adoption; and enhances the strategic relevance of the report for policymakers, funders, and health system planners.

The full proposed checklist is shown in Table 2 and Checklist 1.

The checklist is available for download [15]. A full item-by-item description with text excerpts as examples is provided in Checklist 2. Checklist 1 provides the checklist form for completion at the reporting writing stage. A glossary of terms for ease of interpretation of the checklist items is provided in Checklist 3.

This study introduced what is, to the best of our knowledge, the first horizon scanning checklist designed to enhance transparency, reproducibility, and methodological rigor in the reporting of health technology horizon scanning studies. It presents the results of preliminary work involving analysis of our own reports and in-depth discussions among expert practitioners within the UK horizon scanning center. The checklist outlines identified key features that should be systematically reported to enable comprehensive interrogation and interpretation of intelligence derived from horizon scanning. When our reports were assessed against the checklist, just over one-third of the items (15/35, 42.9%) achieved a final score above 50%, whereas the remaining 57.1% (20/35) of the items were insufficiently reported. This variation in reporting highlights a lack of standardization in current horizon scanning outputs and demonstrates the need for a structured reporting framework. Six checklist items (13, 16, 20, 22, 23, and 25) received a score of 0, meaning that they were not reported in any of the included reports assessed. Some of these items might not be relevant to all technology readiness levels and should not always be reported. For example, a horizon scan in the early horizon that uses patents and preclinical studies to identify trends and signals of innovative technologies will not present sufficient data on outcomes or the strength of the evidence to warrant risk-of-bias or certainty assessments. Furthermore, although it is strongly recommended that a horizon scan follow a robust, pre-agreed protocol, the highly strategic nature of some horizon scans makes a publicly available protocol unfeasible due to confidentiality agreements with stakeholders. Notably, many of these features are already represented in reports from the UK national horizon scanning center, highlighting both their relevance and feasibility. This finding demonstrates the need for more consistent and comprehensive reporting across all horizon scanning studies to support full transparency, comparability, and utility of the findings.

Key strengths observed across well-reported items included the consistent articulation of rationale, eligibility criteria, and technology characteristics, crucial elements for supporting decision-making. However, core methodological domains such as search strategy, selection process, synthesis methods, and discussion of limitations were frequently underreported or absent. These gaps limit the transparency and replicability of horizon scanning studies, potentially reducing their utility for decision-makers involved in regulatory, reimbursement, or research prioritization pathways.

To address these issues, the study team developed a prototype 35-item checklist (including multicomponent subitems), of which 28 (80%) were designated as mandatory and 7 (20%) were designated as optional. These designations were based on the expert consensus of internal team members and reflected both practical constraints and methodological requirements. It is worth stressing that the checklist introduces 4 essential components not found in existing reporting frameworks such as the PRISMA-ScR: interest holder description, scope (HIP-D/I framework), technology characteristics, and PESTLED framework. These additions are fundamental to horizon scanning, which (unlike systematic reviews) uses the technology as the unit of analysis rather than the study or its outcomes. A detailed description of the identified, filtered, and prioritized technologies is critical to enable strategic planning, future assessments, and timely decision-making.

Furthermore, this checklist reflects the exploratory and anticipatory nature of horizon scanning. The emphasis is on the detection of weak signals, in alignment with the goals of identifying transformative technologies ahead of market entry. This reframing supports the unique objectives of horizon scanning, particularly in cases in which conventional data may be unavailable and insights must be drawn from diverse and sometimes non–peer-reviewed sources such as clinical trial registries, patent databases, preprints, and expert consultation.

Horizon scanning is increasingly used by a range of stakeholders (regulators, HTA bodies, policymakers, clinicians, and technology developers) as a forward-looking, market intelligence, and decision support tool [16-19]. Given the variability in how horizon scanning is defined and implemented across organizations, the proposed checklist may provide a common foundation for improving the transparency, comparability, and rigor of horizon scanning practices in health care innovation.

Our study has several limitations. First, the development of the checklist prototype relied exclusively on internal experts from the NIHR Innovation Observatory. While the team possesses extensive experience in conducting horizon scans across a variety of health technologies, stakeholders, and time horizons, we recognize that this internal scope may limit the generalizability of the findings. To address this, we plan to undertake a formal external validation using a scoping review and a multistage adapted Delphi process to achieve broader consensus on item relevance, structure, and applicability across diverse horizon scanning contexts. Second, the checklist scoring was based on a relatively small sample of 17 reports published since 2017. Given the niche nature of horizon scanning in health care, this limited sample size may have influenced the ranking of optional vs mandatory items. Future application of the checklist to a larger set of outputs will help mitigate this constraint and may refine item prioritization. Finally, wild cards did not appear in the analyzed reports because the sample consisted of applied horizon scanning outputs focused on near- to midterm health technologies, where evidence sources and stakeholder priorities typically emphasize plausible and actionable innovations rather than low-probability, high-impact events. Therefore, their absence reflects the empirical characteristics and scope of the sampled material, not a conceptual exclusion from the checklist framework, which is designed to accommodate any signal type if reported but more specifically weak signals and trends.

This study presents the development of a prototype checklist designed to improve the transparency, consistency, and methodological clarity of horizon scanning reports for health care innovation. The checklist was created in response to a recognized gap in reporting standards [6], drawing on elements from the PRISMA-ScR framework [9] to accommodate the broad and exploratory nature of horizon scanning studies, similar to those of broad scoping reviews [20].

The checklist provides a structured foundation for reporting horizon scanning outputs, facilitating more robust and reproducible methods, and supporting stakeholder engagement in early decision-making processes. Its adoption has the potential to contribute to the standardization of horizon scanning practices across organizations, enhance the strategic value of these outputs in innovation management, and provide horizon scanning methods of greater scientific rigor.

Next steps include conducting an external validation using a multistage Delphi process following a rapid scoping review involving a diverse group of horizon scanning experts and end users. This will help refine and potentially increase the checklist items, confirm their relevance across different settings, and promote broader adoption. If widely implemented, this checklist can serve as a key tool for strengthening the scientific basis of horizon scanning and advancing its role in health policy and innovation planning.