Practices and Barriers in Developing and Disseminating Plain-Language Resources Reporting Medical Research Information: A Scoping Review

Abstract

Background

The intent of plain-language resources (PLRs) reporting medical research information is to advance health literacy among the general public and enable them to participate in shared decision-making (SDM). Regulatory mandates coupled with academic and industry initiatives have given rise to an increasing volume of PLRs summarizing medical research information. However, there is significant variability in the quality, format, readability, and dissemination channels for PLRs. In this scoping review, we identify current practices, guidance, and barriers in developing and disseminating PLRs reporting medical research information to the general public including patients and caregivers. We also report on the PLR preferences of these intended audiences.

Methods

A literature search of three bibliographic databases (PubMed, EMBASE, Web of Science) and three clinical trial registries (NIH, EMA, ISRCTN registry) was performed. Snowball searches within reference lists of primary articles were added. Articles with PLRs or reporting topics related to PLRs use and development available between January 2017 and June 2023 were identified. Evidence mapping and synthesis were used to make qualitative observations. Identified PLRs were quantitatively assessed, including temporal annual trends, availability by field of medicine, language, and publisher types.

Results

A total of 9116 PLRs were identified, 9041 from the databases and 75 from clinical trial registries. The final analysis included 6590 PLRs from databases and 72 from registries. Reported barriers to PLR development included ambiguity in guidance, lack of incentives, and concerns of researchers writing for the general public. Available guidance recommendations called for greater dissemination, increased readability, and varied content formats. Patients preferred visual PLRs formats (e.g., videos, comics), which were easy to access on the internet and used short jargon-free text. In some instances, older audiences and more educated readers preferred text-only PLRs. Preferences among the general public were mostly similar to those of patients. Psychology, followed by oncology, showed the highest number of PLRs, predominantly from academia-sponsored research. Text-only PLRs were most commonly available, while graphical, digital, or online formats were less available. Preferred dissemination channels included paywall-free journal websites, indexing on PubMed, third-party websites, via email to research participants, and social media.

Conclusions

This scoping review maps current practices, recommendations, and patients’ and the general public’s preferences for PLR development and dissemination. The results suggest that making PLRs available to a wider audience by improving nomenclature, accessibility, and providing translations may contribute to empowerment and SDM. Minimizing variability among available guidance for PLR development may play an important role in amplifying the value and impact of these resources.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40271-024-00700-y.

Plain Language Summary

Plain-language resources (PLRs) can help people understand medical research information. This will allow them to make informed decisions about their health. However, PLRs vary in quality, format, and ways in which they are shared. In this study, researchers looked at how PLRs are made and publicly shared. They also studied what makes PLRs useful for the public and patients. Creating PLRs is not easy because of unclear guidelines on writing for the public. Using different formats and languages can make PLRs readable. Patients preferred PLRs as videos and comics. Older and educated readers liked text-only PLRs. The fields of psychology and oncology had the highest number of PLRs. Text-only PLRs were more common than digital or online formats. PLRs should be easily and freely accessible. Open-access journal websites, PubMed, third-party websites, email, and social media can be used to share PLRs. This study showed that PLRs can be helpful, but there are challenges in creating and sharing them. Good PLRs can inform patients and help them make better health-related decisions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40271-024-00700-y.

Key Points for Decision-Makers

Plain-language resources (PLRs) are texts, videos, graphics and other content that summarize medical research information for patients, carers, and the general public.

The quality, format, and disseminations channels of PLRs vary significantly, impacting their effectiveness in empowering individuals and facilitating shared decision-making.

Patient preferences for PLRs vary, with some favoring visual formats such as videos and comics, while others prefer text-only versions. Accommodating different audience preferences is crucial for effective PLR development and dissemination.

Introduction

Shared decision-making (SDM) between patients and healthcare professionals is becoming an increasingly important concept in modern medicine [1]. The move toward a more inclusive, patient-centric approach can enable patients to be active participants and decision-makers in their own healthcare [2, 3]. Research has shown that engaged patients lead to improved health outcomes, higher satisfaction with the care experience, and reduced healthcare costs [3–6]. Health literacy levels influence the ability of people to seek, understand, and utilize healthcare information; thus, health literacy plays a defining role in how patients, caregivers, and the general public derive benefit from their interactions with healthcare professionals, manage self-care, and navigate the healthcare system [7]. For patients, caregivers, and the general public to actively participate in SDM, medical research information needs to be readily accessible in a jargon-free, easy-to-understand form [8, 9].

The findings of medical research are predominantly disseminated to healthcare professionals and members of the research community through articles in peer-reviewed journals and presentations at conferences; these are typically data dense and text heavy [10, 11]. These formats of disseminating information are hardly suited to the needs of a nonscientific audience [9, 10, 12, 13]. Taking this into consideration, the US and EU regulatory bodies first expressed interest in making available clinical trial lay summaries on web-based registries in 2007, while stronger recommendations or mandates came in the following years [14–16]. Complementing these efforts, many journal publishers have advocated for the development of plain language summaries of scientific articles or conference presentations [17–19]. Beyond these, there are initiatives by various stakeholders such as public health bodies, research hospitals, and patient organizations to make available plain language materials in various formats including text, graphic, and video summaries and through different channels [20–22]. For the purpose of this paper, the term “plain-language resources” (PLRs) encompasses all of the above types of materials.

PLRs summarize medical research information in a form that is easily understood by a nonscientific audience such as the general public, including patients and caregivers. PLRs can fill the significant unmet need for timely, reliable, and accessible medical research information; they have the potential to facilitate SDM in disease management and enable self-management by patients [8]. In addition to improving patient engagement, PLRs may also help patients and the general public to critically evaluate and identify biased information or disinformation.

Since 2017, there has been a steady increase in the development and dissemination of PLRs by clinical trial sponsors [9, 23, 24]. However, as available guidance varies significantly or is ambiguous and open to interpretation, there is significant variability in the standards of content development [23, 25, 26]. Dissemination channels or hosting locations are also varied, with some nonprofit clinical trial sponsors releasing results in nontechnical language through institutional websites and press releases [27]. Published in-depth analysis of the PLR landscape is limited to qualitative assessment of text-only PLRs of journal articles [9]. However, for PLRs to fulfil their potential, a deeper understanding is needed on what adds the most value to the general public including patients [28–30].

The objectives of this scoping review were: (1) to quantitatively examine the origin, types, and characteristics of PLRs on medical research information currently available; (2) to identify current practices, and barriers to developing and disseminating PLRs on medical research information to the general public including patients and caregivers; (3) to study the preferences of these intended audiences and map available guidance on PLRs to health literacy themes.

Methods

We searched three bibliographic databases, PubMed, EMBASE, and Web of Science. This was complemented by searches on three clinical trial registries—the National Institutes of Health (NIH) Clinical Trials Registry, the European Medicines Agency (EMA) Clinical Trials Register, and the BioMed Central’s ISRCTN registry (the primary registry of the World Health Organization Registry Network). English-language articles from January 2017 to June 2023 were considered. Reference lists of primary studies published in English during this period were also included. We used the framework of Arksey and O’Malley to identify and select eligible articles and collated and summarized the results [31]. This analysis and manuscript were prepared in accordance with the PRISMA Extension for Scoping Reviews (PRISMA-ScR), where applicable [32].

Literature Searches

The search terms used for PubMed are presented in Supplementary Information Table S1 and were modified for use with other bibliographic databases in combination with database-specific filters. An example of the search terms used for the NIH clinical trial registry is presented in Supplementary Information Table S2.

We included (a) articles with associated PLRs (within the main text of the article or accompanying the text); (b) standalone published PLRs; (c) clinical trial result summaries accompanied by a PLR from the three clinical trial registries; (d) standalone PLRs of journal articles published in a different journal; (e) peer-reviewed articles reporting on the types, formats, and dissemination strategies for PLRs; and (f) qualitative, quantitative, and mixed-method articles proposing recommendations or sharing experience on plain language content development or dissemination. With the aim to screen out articles that may not purely be focusing on medical research, we excluded reports of preclinical or basic research, manufacturing, generic treatments (not original research), research in health system models, and those discussing general topics around health literacy, health education, public–patient projects, public health or health policy, research protocols, allied fields such as bioinformatics, genetics, health economics, pharmacology, pharmacogenetics, physiology, surgery, and nutrition (Supplementary Information Table S3). Additional details are provided in the protocol posted on an open-source platform (details at the end of this manuscript).

The titles and abstracts of articles found were screened independently by one researcher (AP, supported by AY and AK who are mentioned under the acknowledgements) to confirm that they met the inclusion criteria and to eliminate duplicates. Full texts were then independently assessed for eligibility by the same researcher (AP), while extraction and cross-checking were done independently by two researchers (AP, TW). Disagreement was resolved through discussion.

Evidence Mapping and Synthesis

Identified articles were classified according to their topic (i.e., quality standards, barriers to development and dissemination, impact of PLRs) or their type (i.e., associated with a journal article, associated with a clinical trial, or standalone PLRs in a different journal than where the original article was published). We defined full set as all relevant records from bibliographic databases that met the inclusion criteria above and clinical trial set as PLRs reporting clinical trial results.

Data Extraction

Two data extraction forms were designed by AP and reviewed by IA and TW. Both data extraction forms compiled published attributes of PLRs such as bibliographic information, digital object identifier (DOI) number, web location, abstract/summary, and article type. The first data extraction form additionally compiled medical specialty, sponsors (based on author affiliation), publisher, and category (journal article with PLR, journal article about PLRs, standalone PLRs of journal articles published in a different journal). PLRs reporting clinical trials were identified based on tagging as a clinical trial on the bibliographic databases and the use of terms “study” or “trial” in the article titles.

The second data extraction form was used to additionally compile study type (qualitative, quantitative), publisher, nomenclature of PLR used, formats of PLRs evaluated, recommendations, or guidance or current practice sharing on the quality attributes of PLRs (language, structure, readability, format), preferences of intended audiences (patients or general public), and impact on knowledge and understanding, dissemination channels, barriers to the development and dissemination of PLRs, and potential impact and limitations of research reported in the articles. Articles that reported qualitative or quantitative assessments or experience (either methodological or involving public or patient respondents) on development and dissemination of PLRs were classified as current practices. Articles that provided consensus or collective or multistakeholder recommendations from academic or industry affiliated organizations on development and dissemination of PLRs, or indicated guidance or recommendation in their titles were classified as guidance. The above extracted information was categorized using the interpretation of health literacy from a patient perspective of Jordan et al. [7], supported by the definitions of health literacy of Abel et al. [33] and Sykes et al. [34] and the association between health literacy and empowerment as interpreted by Crondahl et al. [35]. The categories were mapped to the following broad health literacy themes and specific subthemes:

• Accessibility: Ease of searchability, discoverability; user-friendly, pro-disability content; language characteristics not limited to readability

• Understanding: Ease of understanding based on how the content is structured

• Knowledge: Enablement of knowledge gain based on format of information presentation

• Utilization/empowerment: Self-identification of opportunities for utilization of knowledge

Statistical Analysis

Microsoft Excel-based formulae were used to store and analyze the retrieved articles. Charts of selected data were generated using Microsoft Excel. We performed (1) a trend analysis of PLRs as part of the descriptive quantitative analysis and (2) a qualitative overview of available PLR reporting quality standards/attributes and analyzed them in the context of health literacy principles [33–35]. Post hoc analyses based on summative content analysis methodology as described by Hsieh and Shannon 2005 [36] were performed on PLRs reporting clinical trial results to evaluate the various terminology used in the published literature describing PLRs, and the frequency of PLRs describing positive study results. There is inconsistent naming of PLRs, which is a known challenge with the potential to reduce accessibility [37] and bias toward submission and publication of studies with positive results over negative results [38, 39]. For this purpose, a predefined list of 35 terms (Supplementary Information Table S4) identified by Abola and Prasad 2016 [40] and Vinkers et al. 2015 [41] were searched and quantified across the scientific abstracts.

Results

Origin and Types of PLRs

A total of 9116 PLRs were identified, 9041 from the bibliographic databases and 75 from clinical trial registries. Of these, 6662 were included in the final analysis (6590 from databases and 72 from registries; Fig. 1). There were a total of 55 standalone PLRs and 6532 PLRs accompanying journal articles or clinical trial results. There were 55 articles that discussed the development and dissemination of PLRs. In total, 15.7% of the PLRs reported clinical trial results.

Fig. 1.

Flowchart of the search strategy and screening of articles according to PRISMA [32]. CT clinical trial, PLR plain language resource. Note: Identified articles were classified according to their topic (i.e., quality standards, barriers to development and dissemination, impact of PLRs) or their type (i.e., associated with a journal article, associated with a clinical trial, or a standalone PLR article in a different journal than where the original article was published)

Of the 55 journal articles about PLRs discussing current practices and barriers [8, 9, 12, 21, 23, 24, 37, 42–89], ten articles sharing guidance on PLRs development or related topics were identified [23, 24, 47, 66, 67, 75, 76, 79, 84, 86]. Ten articles were narratives (e.g., commentaries, letters, or short communications) [43, 47, 58–60, 66, 74, 76, 79, 81], and six were literature reviews, including systematic reviews [9, 24, 37, 57, 61, 71]. Seven articles described case studies and case series [21, 48, 50, 55, 84, 86, 88], six described randomized studies [12, 51–53, 63, 82], and 19 reported comparative or correlational research [44–46, 49, 54, 62, 63, 65, 68–70, 72, 77, 78, 80, 83, 85, 87, 89]. For more information on the 55 articles, please refer to Table 1.

Table 1.

Overview of the articles discussing topics related to plain-language resources (N = 55)

References	Guidance or in-practice experience	Study type	Data collection or analysis method	Objectives
Anderson et al. (2022) [44]	In-practice experience	Quantitative study	Surveys	1. Compare the readability of PLRs published in Cystic Fibrosis Research News (CFRN) with paired scientific abstracts published in Journal of Cystic Fibrosis (JCF) 2. Provide recommendations for authors preparing to write PLRs for CFRN
Carvalho et al. (2019) [54]	In-practice experience	Review of literature	Content analysis	1. Investigate the extent to which published reports of research into the effects of physiotherapy interventions provide PLRs 2. Determine if the proportion of these reports that include PLRs is increasing over time 3. Determine if the PLRs that are published are at a suitable reading level for a layperson 4. Determine if the inclusion of PLRs for a randomized trial is associated with trial quality
Kearns et al. (2022) [12]	In-practice experience	Quantitative study	Surveys	Assess participant preferences for the medium they received study results by comparing a novel comic summary, the traditional approach of a lay summary, and a published scientific abstract
Stoll et al. (2022) [9]	In-practice experience	Review of literature	Content analysis	1. Develop a conceptual framework (aims, characteristics, defining criteria, outcomes of PLRs) unifying the topic of PLRs in the scientific literature 2. Synthesize empirical evidence on PLRs by integrating it into the conceptual framework
Zimmerman et al. (2022) [89]	In-practice experience	Qualitative study	Interviews	1. Assess the acceptability of PLRs and thank you notes for purposes of refining and expanding PTN (Pediatric Trials Network) guidance on trial communications with participants in pragmatic pediatric clinical research studies
Dormer et al. (2022) [23]	Guidance/recommendations	Qualitative study	Interviews	1. Describe the development of a “how-to” guide for multistakeholder cocreation of PLRs for peer-reviewed publications
Sedgwick et al. (2021) [24]	Guidance/recommendations	Review of literature	Content analysis	1. Discuss strategies that scientific writers may consider to better facilitate translating scientific literature into PLRs 2. Serve as a guide for authors on crafting the medical literature in a way that is more applicable to the general public
Lobban et al. (2022) [67]	Guidance/recommendations	Qualitative study	Surveys	Provide multistakeholder perspectives on key issues relating to developing and publishing PLRs of company-sponsored medical research
Martínez Silvagnoli et al. (2022) [68]	In-practice experience	Quantitative study	Surveys	Evaluate the preferred readability and format for PLRs of medical research about chronic diseases affecting different age groups, among web-based lay audiences (i.e., patients and caregivers)
Rosenberg et al. (2021) [75]	Guidance/recommendations	Qualitative study	Interviews	Present the Open Pharma recommendations for PLRs of peer-reviewed medical journal publications
Kerwer et al. (2021) [64]	In-practice experience	Quantitative study	Surveys	Evaluating eight hypotheses on approaches for handling technical terms, communicating the quality of data and study methods, operationalization of research questions, handling statistical terms, structuring PLRs, and explaining complex meta-analytic designs
Edgell et al. (2022) [56]	In-practice experience	Qualitative study	Interviews	Perspectives of five day-to-day users of PLRs from different stakeholder groups
Maurer et al. (2021) [21]	In-practice experience	Qualitative study	Interviews and Focus groups	To describe the Patient-Centered Outcomes Research Institute’s (PCORI) approach to and lessons learned from developing PLRs of PCORI-funded research for the lay public
Dormer et al. (2020) [55]	In-practice experience	Qualitative study	Observations	Introducing a new type of PLR
Getz et al. (2019) [58]	In-practice experience	Nonempirical study	Commentary	Looks back over the past 10 years to examine the low level of compliance and slow progress that has been made in meeting the ethical obligation to return PLRs
Bruce et al. (2022) [50]	In-practice experience	Qualitative study	Content analysis	To develop infographic-based PLRs on the current management guidelines for mucopolysaccharidosis (MPS) VI and MPS IVA
Smith et al. (2021) [81]	In-practice experience	Nonempirical study	Commentary	Landscape overview
Penlington et al. (2022) [70]	In-practice experience	Quantitative study	Surveys	1. Understand the utility of the EU Clinical Trials Registry to help build trust, we conducted two surveys across three continents to explore the level of public interest in vaccine clinical research 2. Survey participants to help develop PLRs that effectively communicated the essential information required to meet their expectations
South et al. (2021) [82]	In-practice experience	Qualitative study	Interviews and Focus groups	Generate evidence to inform trial teams on how to share results with trial participants through a mixed methods cluster randomized factorial study
Anand et al. (2021) [43]	In-practice experience	Nonempirical study	Short communication	Landscape overview
Gudi et al. (2021) [59]	In-practice experience	Nonempirical study	Commentary	Landscape overview
Penlington et al. (2020) [71]	In-practice experience	Review of literature	Content analysis	Assess: (i) 20 top pharmaceutical companies’ positions on improving transparency and commitment to disclosing trial result summaries in an easy-to-understand format and (ii) the availability of such summaries in the public domain and the ease of locating them via general web search
FitzGibbon 2020) [37]	In-practice experience	Review of literature	Content analysis	Investigate how the discoverability of PLRs is being handled by biomedical journals
Buljan et al. (2020) [52]	In-practice experience	Qualitative study	Focus groups	Explore consumers’ preferences for different summary formats of Cochrane systematic reviews (with blogposts versus with text PLRs)
Buljan et al. (2020) [53]	In-practice experience	Quantitative study	Surveys	Explore how different framing of numerical information influences understanding of information in Cochrane systematic PLRs
Wada et al. (2020) [84]	Guidance/recommendations	Qualitative study	Focus groups	Develop lay summary cocreation guidelines for researchers that will ultimately be made widely available to researchers across a variety of disciplines, sectors, and institutions
Stricker et al. (2020) [83]	In-practice experience	Qualitative study	Document analysis	Compare the readability of scientific abstracts and PLRs in psychology based on reproducible readability indices
Bredbenner et al. (2019) [49]	In-practice experience	Quantitative study	Surveys	Evaluate the effectiveness of different summary types for people with different careers. Looked at comprehension, perceived understanding, enjoyment, and whether the participants wanted to see more summaries of that type to determine which summary method is most effective
Barnes et al. (2019) [47]	Guidance/recommendations	Nonempirical study	Commentary	Landscape overview
Aldinger et al. (2018) [42]	In-practice experience	Quantitative study	Surveys	Understand the preferences of and test a template for, sharing study results with participants of integrative medicine therapies at a regional cancer center and of a mind–body service within a general hospital
Whiting et al. (2018) [86]	Guidance/recommendations	Quantitative study	Surveys	Step-by-step guidance for authors of diagnostic test accuracy reviews for writing PLRs
Raynor et al. (2018) [72]	In-practice experience	Qualitative study	Interviews	Apply user testing to maximize the readability and acceptability of a Clinical Trial Results General public Summary to determine whether it meets audience needs, including those with a range of health literacy levels
Buljan et al. (2018) [51]	In-practice experience	Quantitative study	Surveys	Compare information presentation in an infographic with that in standard text PLRs and scientific abstract formats, in terms of gaining knowledge about research results presented in a Cochrane systematic review
Pushparajah et al. (2018) [8]	In-practice experience	Qualitative study	Interviews	Determine the value of developing PLRs of peer-reviewed articles among the two main target groups, patients and physicians, through a series of cross-sectional surveys and interviews
Kirkpatrick et al. (2017) [65]	In-practice experience	Quantitative study	Surveys	Assess two possible methods of improving readability and understanding of plain English summaries (PESs) published in the National Institute for Health Research (NIHR) Journals Library: (i) Providing enhanced guidance to authors and asking them to rewrite the PES and (ii) Employing an independent medical writer to edit the PES
Barnfield et al. (2017) [48]	In-practice experience	Qualitative study	Focus groups	1. Select and prioritize individual studies from the COGFAST (Cognitive Function after Stroke) project of relevance and interest to members of the public 2. Produce lay summaries relating to the selected studies 3. Make these lay summaries accessible to the public via a website
Shailes et al. (2017) [79]	Guidance/recommendations	Nonempirical study	Commentary	Landscape overview
Kuehn et al. (2017) [66]	Guidance/recommendations	Nonempirical study	Commentary	Landscape overview
Banic et al. (2022) [46]	In-practice experience	Quantitative study	Content analysis	Conduct a comprehensive analysis of conclusiveness, linguistic characteristics and readability of PLSs on all the available Cochrane PLSs of intervention studies published in English until February 2019. Analyze trends of these variables in the analyzed time frame and explore whether these variables differed across different Cochrane Networks
Gainey et al. (2022) [57]	In-practice experience	Review of literature	Content analysis	Provide a better understanding of the PLR instructions currently available to authors
Rosenberg et al. (2023) [76]	Guidance/recommendations	Nonempirical study	Commentary	Landscape overview
McGrath et al. (2023) [69]	In-practice experience	Quantitative study	Content analysis	Compare five commonly used readability calculators employing three sources of text narrative from (i) children’s fairy tales, (ii) BBC medical reports, and (iii) scientific abstracts, to suggest to the clinical trials community a robust and widely accessible calculator for standardized use when accessing the readability of clinical trials patient-facing materials
Habr et al. (2023) [60]	In-practice experience	Nonempirical study	Commentary	Landscape overview
Shiely et al. (2023) [80]	In-practice experience	Quantitative study	Content analysis	Assess the readability and plain English compatibility of a sample of PLRs from the National Institute for Health and Care Research (NIHR) reports of randomized trials
Wen et al. (2023) [85]	In-practice experience	Quantitative study	Content analysis	Examine to what extent PLRs published in Autism Research have fulfilled their intended objective of making scientific discoveries accessible to relevant stakeholders from both the academic and nonacademic communities through the lens of readability
Yi et al. (2023) [87]	In-practice experience	Quantitative study	Content analysis	Determine (i) if PLRs published in Autism are more readable than traditional abstracts, and (ii) if PLRs published in Autism are readable enough for the general public
Ruzich et al. (2023) [77]	In-practice experience	Quantitative study	Surveys	Develop a brief, informative, and understandable resource sheet summarizing patient-reported outcome data from a prostate cancer clinical trial in line with presentation preferences of patients
Helmer et al. 2023) [61]	In-practice experience	Review of literature	Content analysis	Identify (i) dissemination strategies and (ii) stakeholders of Cochrane Public Health reviews
Schmitz et al. (2023) [78]	In-practice experience	Qualitative study	Document analysis	Assess lay summary development capabilities of three artificial intelligence tools: CoPilot, Wiseone, and ChatGPT
Kerwer et al. (2021) [63]	In-practice experience	Qualitative study	Focus groups	Empirically investigate: (i) if PLRs are better suited for communicating research findings to lay audiences than ordinary scientific abstracts; (ii) whether the structure of PLRs influences their comprehensibility; (iii) examining the effect of provision of PLRs on patient trust in research findings and the emotional and behavioral consequences; iv) individual differences in response to PLRs and their predictors
Zając et al. (2019) [88]	In-practice experience	Qualitative study	Content analysis	Analysis of advantages and difficulties connected with dissemination of evidence-based knowledge using the example of PLRs shared through social media in Poland
Anzinger et al. (2021) [45]	In-practice experience	Quantitative study	Content analysis	Investigate parents’ views of PLRs, blogshots, and Wikipedia to further increase their usability and inform future knowledge translation tool creation
Raza et al. (2020) [73]	In-practice experience	Quantitative study	Content analysis	Assess whether researchers in the UK intend to inform participants of the trial results, plans for how results are provided, how patients are involved in this process, and finally, whether those trial teams that intended to provide results report this activity in their End of Study reports
Rodgers et al. (2017) [74]	In-practice experience	Nonempirical study	Commentary	Landscape overview
Hinckley et al. (2023) [62]	In-practice experience	Quantitative study	Content analysis	Discuss the motivations behind disseminating research in understandable ways and provide information about procedures and resources for publishing plain language summaries, video summaries, or graphical abstracts

Frequency of Availability and Published Attributes of PLRs

The annual number of PLRs grew progressively from 369 in 2017 to 2159 articles in 2022, reaching a peak of 2156 articles in 2021 (Fig. 2A). The number of PLRs peaked between 2020 and 2022, which appeared to coincide with the COVID-19 pandemic; however, any predominance of infectious diseases PLRs was not apparent. Considering the ten most common medical specialties (psychology, oncology, hepatology, infectious diseases, cardiology, reproductive health, neurology, gastroenterology, endocrinology, immunology), PLRs reporting results of psychology research (n = 1329) predominate over other fields (Fig. 2B). Oncology and hepatology, have the next highest availability of PLRs (n = 1012 and n = 932, respectively), with oncology having the highest number (n = 243) among PLRs reporting clinical trial results.

Fig. 2.

PLRs (all and clinical trial-related) by publication year (A), top ten fields of study (B), and publisher (C); number of positive terms mentioned in the clinical trial PLR set (D). CT clinical trial, PLR plain language resource

By sponsor types, PLRs reporting results of academia-sponsored research were more numerous (n = 5614) than those supported by pharmaceutical organizations (n = 469) or nonprofits (n = 463) in both the overall set and clinical trials. When assessed by journal publishers, Wiley had published the highest number of PLRs (n = 1374), followed by Elsevier, Future Medicine, and Springer Nature (Fig. 2C).

Post hoc analysis of the PLRs reporting clinical trial results (n = 1078) showed that 79% of the PLRs did not use the predefined positive terms to describe their conclusions. The frequency of use of the positive terms in the clinical trials set is summarized in Fig. 2D. “Novel” (n = 66) was the most commonly used term, followed by “promising” (n = 35) and “unique” (n = 32).

Lay summary and plain language summary (PLS) were the most frequently used terms to describe PLRs, with others including (in decreasing frequency) lay abstract and plain English summary (Fig. 3). Overall, this analysis found 26 different terms for PLRs, 20 of which were only found in single instances.

Fig. 3.

Nomenclature used for plain language resources (full set). CT clinical trial

Current Practices to Improve Accessibility, Understanding, Knowledge, and Utilization of PLRs

Current practices in PLR development were reported in a subset of articles describing methodological approaches to PLR development [37, 46, 57, 69, 80, 83, 87]. Accessibility to PLRs was increased by making them freely available even when they are included within articles (even if the main article is paywalled), or through sharing on social media or hosting them alongside the abstract in PubMed [37, 83]. PLRs were also made more accessible by adapting the content to the expected education level of the audience by using appropriate language level and by minimizing jargon and use of passive voice [37, 57, 69, 80, 87].

Understanding of content among the target audience was improved by using PLR text of appropriate length and structure. While journal recommendations for length for text PLR vary widely (e.g., from 80 words to up to 850), there is flexibility to use longer text in PLR describing more complex or conflicting findings and using more structured formats with predefined subheadings or Q&A [57, 80]. These articles reported improvement in PLRs through use of readability tools and calculators but concluded that these should not be seen as a replacement for patient’s or general public’s feedback [23, 24, 67, 75, 84, 86]. Knowledge transfer from PLR content was also increased compared to scientific literature through text-only formats, audio formats, and graphics/infographics, and graphic formats were reported to be particularly useful for informing an autistic audience [83, 87]. Practices promoting empowerment included the inclusion of laypeople or patients in PLR development and writing in a focused and clear style that answers the audience’s medical questions [37, 46, 80, 87].

The most commonly discussed format in articles about PLRs included text-only PLRs (of various levels of detail up to and including scientific abstracts) [8, 9, 12, 21, 42, 44–46, 48, 49, 51, 52, 54, 57, 58, 61–65, 68, 70–72, 74, 75, 80, 83–89]. Some articles discussed visual forms of PLRs, including text and graphic PLRs (including infographics) [9, 49–51, 53, 55, 62, 68, 70, 75, 77, 89], comics [12, 83], or videos [49, 62]. Online forms of PLRs considered included webpages, blogposts, and social media posts [45, 52, 82, 88]. Some articles included scientific abstracts as a comparator to more simplified formats [44, 51, 63, 83, 85, 87]. Seven discussed all formats of PLRs that may accompany research findings [37, 47, 56, 60, 76, 79, 81]. Nineteen studies reported audience preferences for different PLR formats [12, 21, 44–46, 48, 49, 51, 52, 63–65, 68, 70, 77, 83, 85, 87, 89]. Audience preferences on structure, language, content presentation, and hosting location are presented later under Sect. 3.5.

Available Guidance on PLR Development and Dissemination

In the ten articles offering guidance for PLR development, available guidance focused on the following needs and components: consistent criteria for selecting studies/datasets for PLR development [23, 67], consistent policy guiding PLR development [23, 67], training and creating awareness among stakeholders about PLRs [47, 67], understanding the target audience’s needs [23, 67], establishing a reliable review process (both for developers and journal publishers) [23, 67, 75, 86], always providing context of the findings and linking back to the source article [75], carefully timing the release of PLRs [47], and monitoring impact [23]. These guidance articles also included detailed advice regarding the accessibility and dissemination of PLRs [23, 76], and recommendations on readability, language, formats, and structure [23, 24, 47, 67, 75, 76, 84, 86]. Common themes for language and structure of content included recommendations to avoid jargon and abbreviations [24], use of concise titles and shorter sentences [24, 84, 86], and to take into account the needs and reading level of the intended audience [23, 24, 67, 76, 84]. Specific recommendations on improving discoverability included pointers to make these materials available via paywall-free, publicly available channels such as websites, social media, and emails [23, 24, 47, 67, 76]. These recommendations are summarized in Supplementary Information Table S5 and are presented in more detail below.

Various options were discussed for dissemination channels [23, 24, 47, 66, 67, 75, 76, 79, 84, 86]. Proposed dissemination channels included paywall-free journal websites, publicly accessible websites, indexing on PubMed, third-party websites (for example, Kudos and Figshare), clinical trial center/institutional websites, or by email to research participants and social media. The guidance articles’ advice on accessibility, discoverability, language, structure, and format were generally consistent with the preferences expressed by the general public and patient audiences (Supplementary Information Table S5), although several options for access in these guidance articles, namely investigator websites and direct emails, were not suggested by patient and general public audiences.

Among the guidance documents identified, some contradictions were evident; for example, several of these recommended a maximum length of 250 words for a text summary [75, 76, 84], but another recommendation for text length ranged from one to three pages [67]. Another source of inconsistency is that although the guidance documents suggest many options to improve the accessibility and readability of PLRs, they are largely nonprescriptive and leave many decisions on format and accessibility open to PLR developers.

General Public and Patient Preferences to Improve Understanding, Knowledge and Accessibility of PLRs

Nineteen of 55 studies compared audience (patients and general public) preferences for PLR formats [8, 12, 21, 45, 48–53, 56, 63, 64, 68, 70, 72, 77, 82, 89], five evaluated different text-only formats, eight compared text PLRs with scientific abstracts [8, 21, 48, 53, 64], two compared text PLRs with blogshots [45, 52], and one compared various summary formats with Wikipedia posts [9]. Other comparisons included text PLRs with news reports [66]; five compared text PLRs versus visual formats such as infographics, visual abstracts, infographics, or comics [12, 49, 68, 70, 89]; and one study compared PLRs in different webpage formats [82]. Two of the studies were randomized controlled trials [12, 64].

Patient preferences for PLRs were reported in nine of 55 articles (Table 2) [8, 12, 50, 51, 53, 68, 77, 82, 89] and the general public’s preferences were reported in ten articles (Table 3) [21, 45, 48, 49, 52, 56, 63, 64, 70, 72]. Accessibility preferences of patients included a preference for visual forms of PLRs such as comics and infographics, easy online accessibility, and, in some cases, a preference for text-based summaries of key observations over detailed, quantified data points (Table 2). Regarding understanding, for text-only PLRs, patients preferred shorter jargon-free text written for a lower reading level, with several studies reporting a Q&A style as a preferred format [21, 48, 72, 89]. Patients generally agreed that PLRs were an appropriate tool to enable knowledge sharing and promote greater engagement and discussion with healthcare professionals [12, 68, 77]; health literacy was considered a predictor of the level of understanding [51]. Patients wished for PLRs to be translated into languages other than English to enable wider accessibility [12, 53, 82]. They also expected that limitations of research and more details on specific side effects should be acknowledged in PLRs [77, 89], and that these materials be hosted on websites managed by regulators, healthcare organizations, or patient advocacy groups to improve perceptions of credibility [77]. Patients’ experience suggested that knowledge acquisition was easier or higher and more enjoyable with visual or digital formats and preferred those over text-only summaries [12, 50, 82, 89], although short text-only summaries were deemed satisfactory in most instances [8, 52, 53]. One study, however, reported a preference for text-only PLRs over infographics among older age groups or more educated readers [68]. Patients believed PLRs could empower/be utilized by a more diverse audience through the use of various formats and help patients be more confident in coping with their daily self-management and in participating in discussions with their physicians [8, 12, 50].

Table 2.

Overview of articles (N = 9) reporting results of patients’ preference assessments of plain-language resources. For a description of trial objectives, refer to Table 1

References	Health literacy preferences	Special guidance to improve PLRs	Limitations identified in the article
Kearns et al. (2022 (RCT)) [12]	Accessibility: Comic PLRs were easy to access, read and share; comic PLRs did not require scientific training; text lay summary was easy to read on mobile devices; comic PLRs could reduce literacy barriers and maintain engagement better lay summary and scientific abstract; PLRs should be available in language other than English Understanding: Comic PLRs were preferred by patients except those 18–24 years old who preferred scientific abstracts Knowledge: Comics were easier to understand and more enjoyable; lay summary was appropriate for readers who disliked the comic’s humor Empowerment: Comic PLRs may engage a more diverse audience than other formats	Comic PLRs should avoid having distracting visuals and avoid undermining serious topics with humor, or appearing childish	Limited geography and ethnicity of study participants
Zimmerman et al. (2022) [89]	Accessibility: Text PLRs should be written at an eighth-grade reading level Understanding: Purpose, methods, and efficacy and safety data should be clearly stated; subheadings and Q&A structure can help understanding; links to further information should be provided Knowledge: Strong audience preference for formatted PLR including graphics, versus unformatted, text-only PLRs	Address the audience’s interest in whether the investigative drug is effective or not	Purposefully sampled so not representative; all participants were female
Martínez Silvagnoli et al. (2022) [68]	Accessibility: Preference for infographic and medium complexity text PLRs versus text-only PLRs; lowest complexity PLR was perceived as too simple Understanding: Infographic and medium complexity text-only PLRs were preferred; infographics were preferred by 19–35-years age group; medium complexity text-only PLRs were preferred by ≥ 55-years age group and those with higher education Knowledge: PLRs were perceived as an important tool for improving health literacy	Consider audience preferences during PLR development	Participants had a higher education than the general population; most participants were female
Bruce et al. (2022) [50]	Understanding: Patients view PLRs as tools to enable knowledge sharing; use of plain language and clear images can improve understandability for non-native English speakers Knowledge: Preferred infographic PLRs over text-only PLRs; visual design theme may engage adolescent/young adult audience Empowerment: PLRs can help patients cope with disease in daily life and raise awareness of disease	Oversimplifying technical terms may lead to loss of detail; English-only PLRs are not sufficient	Infographic PLRs were developed with feedback from senior members of patient advocacy groups, feedback from an audience of patients is needed
South et al. (2021) [82]	Accessibility: Ease of access is important to patients; lack of internet access or digital literacy are barriers; lack of clear timelines for receiving information is a problem; patients may prefer to receive study results in a more personalized form; patients may be dissatisfied if PLRs are difficult to understand or lack detail Understanding: Printed PLRs were preferred to digital formats	When sharing PLRs summarizing clinical trial results, the health and computer literacy of the audience should be considered; PLRs should be in a form that allows patients to keep them	Inability to discern if there were differences between respondents and nonrespondents in other potentially relevant characteristics
Buljan et al. (2020) [53]	Accessibility: PLRs should be easily accessible (e.g., first page of web searches, or via family physician); PLRs should be translated into languages other than English Understanding: No difference in understanding if data are presented as percentages or natural frequencies, or if information is framed positively or negatively	Research organizations should cooperate with governments to create formats for PLRs that are appropriate and accessible to the lay population	Most participants did not suffer from the conditions described in the summaries
Buljan et al. (2018) [51]	Accessibility: Patients preferred infographic PLRs, then text summary over scientific abstract for knowledge, reading experience, and user friendliness; Understanding: Health literacy was a predictor of knowledge Knowledge: Text summaries and infographic PLRs were similarly effective for informing patients about a systematic review		The study population was small; PLRs used in the trial were written by a professional writer and Cochrane reviewer; participants who completed the survey presumably had a higher degree of motivation and may have been different from those who did not complete it
Pushparajah et al. (2018) [8]	Accessibility: PLRs distributed by physicians were a useful tool for patient-physician discussions Understandability: Patients found information in text-only PLRs generally understandable and relevant Empowerment: Text-only PLRs provide greater knowledge and confidence and a sense of empowerment	Developers should aim to make PLRs available via the most frequent info sources for patients: Internet searches, patient organization websites and scientific journals (electronic or print)	Small study population. Patients were relatively older (> 35 years), some were advocates and hence more experienced than the overall patient population
Ruzich et al. (2023) [77]	Accessibility: Qualitative data in PLRs increases the accessibility of quantitative data which may alienate or objectify some patients; judicious use of color and design principles in PLRs; PLR authors should observe patient preference for percentiles in communicating quantifiable results to improve accessibility Understanding: Participants found PLRs to be useful, easy to interpret, and relevant; established clinically meaningful changes may not be equally meaningful to all patients; some may prefer more detailed information about specific side effects over the domain-level PRO data presented in the PLR Knowledge: Preferences for certain figure types were not always clearly associated with understanding, but with systemic disparities in health literacy; audience preference for different chart formats must be considered Empowerment: Visual clinical trial PLRs can support patient-clinician discussions about treatment options; patients are enthusiastic about sharing clinical trial data with healthcare professionals; patients emphasize the importance of decision-relevant information	Developers should maintain objectivity and rigor of the data and consider that interpretation may be based on emotional impact and perceived relevance to their specific experiences; patients’ perceptions of PLR credibility would be enhanced if PLRs are hosted on a website managed by regulators, professional organizations, healthcare systems, or patient advocacy groups	The study population may not be representative of other populations, especially in terms of education level; visualizations in PLRs were not systematically selected

Table 3.

Overview of articles (N = 10) reporting results of lay audience preference assessments of plain-language resources. For a description of trial objectives, refer to Table 1.

References	Health literacy preferences	Special guidance	Limitations identified in the article
Kerwer et al. (2021) [64]	Accessibility: Replacing technical terms in the text, glossary, fewer details on research question, and no glossary of statistical terms improve user experience of PLRs; structured format (bullets, use of bolding) improves readers’ experience of complex content Understanding: Explaining of the methodological approach underlying meta-analyses improved understanding and knowledge of the quality of evidence Knowledge/empowerment: Explaining technical terms in the text and in a glossary improves perceived accessibility, understanding, knowledge and empowerment	PLRs should not provide extensive information on the operationalization of synthesized studies; emphasis should be on interpreting the effect size without additional details	Limited generalizability due to target population included; study design did not allow comparison of the same PLRs with different complexity
Edgell et al. (2022) [56]	Accessibility: Patients tend to find PLRs incidentally when looking for research articles; PLRs can speed up the sharing of science by helping understanding of research content more quickly; PLRs should be written so that they can be understood by non-experts; PLRs should be written with short words, short sentences, short paragraphs Understanding: PLRs must capture the key points of the research—main objectives, key takeaways Knowledge: PLRs should acknowledge limitations and be hosted on a trustworthy neutral platform Empowerment: PLRs may be a gateway into the literature for proactive patients to learn more about their conditions and participate in shared decision-making. PLRs can help communicate clinical trial results to patient groups. Helpful for informing the language used in patient materials. help caregivers find new research.	Non-experts should be involved in the development of PLRs; coproduction with patient groups can ensure that the summaries contain the information that patients need
Maurer et al. (2021) [21]	Accessibility: PLR authors should reduce jargon and define technical terms; use short sentences and unify points within a paragraph; test with intended audiences for intended comprehension; and assess reading level Understanding: PLRs should be structured into sections based on key questions (e.g., Q&A format); results and conclusions should be positioned before other information (e.g., methods); PLRs should convey impartiality and limitations	Structure and process for PLR development require balancing precision with simplicity, completeness with brevity; the developer requires deep knowledge of what the readers need to know
Penlington et al. (2022) [70]	Understanding: Q&A format is more appropriate PLR style; study background and implications should be included, as should directions to further information and contact details Knowledge: Infographics PLRs were strong communicators and more helpful when compared with text only; visual format PLRs with less detailed information tended to be easier to understand and more engaging than an elaborate diagram; preferred format varied slightly for different topics related to clinical trial results		Response rate and country specificities limit generalizability
Buljan et al. (2020) [52]	Accessibility: The Cochrane website was perceived suitable only for more sophisticated readers; the internet is often the primary source of health information; other sources included books, friends, family, and doctors; scientific websites are rarely visited; numeric data should be decreased to a minimum or eliminated; PLRs should be presented both visually and textually Understanding: Patients preferred the blogposts to Cochrane website and these had significantly higher comprehension scores; PLR should be easily available, structured, consistent in presentation, explicit, brief, using plain language, and with numbers presented in a table and/or visually Knowledge: Textual information was considered enough; if visual information is needed, it should be limited to a single table and/or image	Blogshots could be a suitable format to engage with the widest community	Generalizability may be limited by the participant population who were who were motivated and had potentially greater knowledge about health evidence than the general population
Bredbenner et al. (2019) [49]	Accessibility: Videos and text PLRs had the highest enjoyment scores for scientific and nonscientific audience Understanding: Video and text PLRs are preferred over scientific abstracts and graphical abstracts, irrespective of learning preferences; in some cases, videos were preferred over text PLRs; strong correlations exist between reported learning preferences and summary of choice Knowledge: Videos are most preferred for comprehension, understanding, enjoyment, and desired updates; text PLRs often have equal scores to videos	Revisions based on feedback from a member of the intended audience and possibly using a jargon detection program can ensure PLRs are accessible; infographics could be more successful than graphical abstracts as they combine text and images	Podcasts PLRs were not considered; video PLRs have limitations given the inherent cost and time of development
Raynor et al. (2018) [72]	Understanding: PLRs can be structure around a standardized list of questions to improve understanding; extraneous information that was not directly related to a section header should be moved elsewhere in the document; PLRs should use easy to understand subheadings while presenting results
Barnfield et al. (2017) [48]	Accessibility: PLRs can be made available as a PDF to print; website links and contact information could be added to original papers; definitions should be less clinical but “dull down” the text; no need to quantify findings (numbers may not matter and less statistics); short and simple lay summary headings are impactful; a separate glossary of terms is preferable to explanations within the PLR Understanding: A Q&A PLR format is most appealing; text should be presented in small separate sections; aims should be placed earlier in the summary; color, images and text in small sections to make the summary more engaging Knowledge: Pictures are preferred to graphs and tables but should be easy to interpret		Limited generalizability as participants were more educated, scientifically aware and had higher baseline awareness from care-giving activities
Kerwer et al. (2021) [63]	Accessibility: Participants had positive emotions (e.g., curiosity) and negative emotions (e.g., confusion, boredom and frustration) toward scientific abstracts versus text PLRs. Text PLRs with subheadings were less boring, less frustrating, and less confusing than scientific abstracts or text PLRs without subheadings Understanding: PLRs should have predefined subheadings: plain review title, the aim of the review, key messages, what was studied, what the main results are, and how up-to-date the PLR is; text PLRs with subheadings enabled higher comprehensibility, perceived credibility, perceived ability to evaluate the study, and perceived ability to make an informed decision; English proficiency had no significant effect on perceived comprehensibility; justification beliefs (i.e., beliefs on criteria for “accepting” knowledge claims) and English proficiency predicted perceived comprehensibility but not knowledge acquisition perceived credibility
Anzinger et al. (2021) [45]	Accessibility: Cochrane blogshots were preferred to other PLR formats (Wikipedia and Cochrane PLRs) and were the easiest to use; no significant difference was perceived between Cochrane PLRs and Wikipedia; PLRs should use repetition selectively and sparingly; avoid abbreviations, jargon, and polysyllable words to make writing easy to understand Understanding: Blogshots are ranked highest in most domains except understandability, where participants narrowly preferred Wikipedia; PLRs introduction should contain symptoms so a reader can determine relevance; include information on how to manage a child, when to seek care, and what to expect; only include statistics from the research if they are meaningful to a caregiver not familiar with the condition; no difference in efficiency among the three formats and no difference in terms of reading time and knowledge retention Knowledge: Parents prefer blogshots over Cochrane PLRs or Wikipedia for aesthetics, ease of use and general preference; no significant differences were reported in the credibility of the three tools; headings and bullet points should be used in PLRs; replace words with graphics wherever possible; be concise, but link to more information; details confuse readers and reduce readership Empowerment: Parents want PLRs that are simple, trustworthy, and quick to access and use, and informative on child health evidence	Wikipedia, has characteristics that make it look official, such as citations, complex terms, and familiar sources contributing to perceptions of credibility	Small study population, higher education levels, and selection bias may limit generalizability

Preferences among the general public were similar overall to those of patients (Table 3). Shorter-form and jargon-free text PLRs, videos, and blogshots were considered more accessible than scientific abstracts and PLRs from sources such as the Cochrane Collaboration [45, 64, 70]. Several studies reported Q&A-structured text-only PLRs as an appropriate format [21, 70], with a preference for shorter words and sentences and the definitions of technical terms provided [21, 56, 63, 72]. Provision of links to further information or author contact details were also reported as a preference in some studies [45, 48, 56, 70]. Across all studies, general public stressed the value of PLRs in helping nonexperts understand and share science more rapidly and as a reliable information source for those proactive about self-managements [21, 45, 48, 49, 52, 56, 63, 64, 70, 72].

The inclusion of intended audience members in the development of PLRs was suggested in feedback from both general public and patients [49, 56], as was the provision of non-English translations [12, 53, 63, 82]. The main limitation cited by reports of both patient’s and general public’s preferences was the generalizability of the study findings, as study populations were usually small and often more motivated or educated than the general population [8, 45, 48, 51, 52, 64, 68, 70, 77]. Several patient studies reported gender imbalance or limited ethnic diversity [12, 68, 89].

Barriers in Developing and Disseminating PLRs

The reported barriers to PLR development included concerns of low readability, resource constraints, insufficient dissemination, exposure to liability, and a lack of incentives for authors to produce PLRs. Readability and audience-related concerns included researchers’ ability to write at an appropriate level and length for the general public [23, 24, 44, 64, 81, 83, 88]. Similarly, the complexity of incorporating the audience’s information preferences or reading ability was also noted [23, 24, 58, 68, 73, 77]. Four articles cited a lack of guidance on the development of appropriate PLR formats for audiences [9, 67, 68, 76], and identification of target audiences was hindered by inconsistent naming of PLRs [37, 76]. Resource constraint barriers included the skills, time, and costs required for the creation of visual formats, especially if additional expertise (e.g., professional graphic designers) would be required [12, 58, 65].

Dissemination barriers discussed in the included articles were the limited platforms for dissemination [67], and the limited options for indexing, tagging and search-engine optimization of PLRs that reduces their discoverability [71, 74, 76]. Other barriers were the inconsistent naming of PLRs as a barrier to discoverability [37, 60, 76] and that digital-only distribution of PLRs may not reach audiences with poor internet access or digital literacy [73, 77]. Concerns related to liability included the disclosure of uncertain, sensitive, misleading, or promotional information [52, 58, 83, 89]. Privacy concerns surrounding patient data were reported [42], as was loss of control if authors outside of the research team were involved in PLRs development [60, 65]. A related concern was content differences between original PLRs and foreign-language translations [47]. Furthermore, a lack of incentives (positive or negative) or guidance to create PLRs was noted [58], including an absence of guidance on the purpose of PLRs, or on which types of articles should have PLRs [88]. The low uptake of PLRs, particularly among high-tier journals, was also perceived as a barrier [54, 76].

Discussion

This is, to our knowledge, the first scoping review that extensively captures the evolution in the landscape of PLRs (quantitative evaluation of all formats and dissemination channels) from its formative years until recent developments. We also report an in-depth qualitative analysis of current practices, existing guidance and barriers in disseminating PLRs reporting medical research information. Improving health literacy has been shown to positively influence a patient’s self-care in disease management, outcomes, medication adherence, and help lower healthcare costs [35, 90–93]. Further, given the complexity of the present healthcare systems, PLRs can help patients make informed choices related to their self-care, derive greater benefit from their interactions with their healthcare providers, and also help them navigate healthcare systems [8, 9, 94]. Hence, we contextualize the findings uniquely by drawing connections between the trends related to PLRs and patient health literacy. To do so, we categorized our findings as per the principles of health literacy from the perspective of patients, as outlined by Jordan et al. [7], which are distinct from the classical health literacy framework originally proposed by Nutbeam [95].

Our analysis shows a progressive increase in the availability of PLRs over the period evaluated, reaching a peak in 2021. The subsequent years showed a dip, but this may be attributed to the time lag associated with the publication of research output. We also noted that not all forms of medical research are equally represented. There were few records from clinical trial registries (Fig. 1), suggesting that many clinical trial PLRs are not available despite the recommendations from key drug regulators [14–16]. This leaves a significant gap in public information on what medical research is currently ongoing.

The substantially higher number of PLRs for a few specialties such as psychology, oncology, and hepatology when compared with other specialties, such as immunology, might indicate that less reliable, easy-to-understand medical research information is available for these specialties. This imbalance could potentially lead to a spurt in misinformation in these specialties [96]. While publishing trends from our analysis show promise in terms of increasing availability, there is a clear need for wider support, especially by highly indexed journals [76], to increase availability as well as improve the quality of PLR being developed. In the modest number of PLR articles reporting clinical trial results identified, the use of positive terms to report outcomes was not evident; however, this observation should be interpreted with caution given the small sample size.

Our research provides a detailed overview of the preferences of patients and general public audiences when accessing medical research information. As anticipated, these audiences struggle with jargon, unstructured and text-heavy content, or lack of information in a language they are comfortable with. Their searches are often hindered by paywalled content or the variability in nomenclature and dissemination channels of PLRs [37]. Audiences appear to trust independent sources such as websites of drug regulators and patient advocacy groups regarding medical information they find online [77]. For patients and the general public to derive the true value of PLRs and for these resources to be impactful, all of these barriers in accessibility and quality will have to be addressed.

Among the literature on barriers to PLR implementation, a perceived lack of guidance on PLR development is reported [9, 67, 68, 76]. We identified ten articles offering such guidance [23, 24, 47, 66, 67, 75, 76, 79, 84, 86]. This may reflect a lack of awareness of existing guidance or a need for a more structured oversight of the PLR development process. Quality assessment of available guidance was out of scope of this scoping review, hence, there needs to be further investigation on whether current guidance is comprehensive, useful, and is being implemented by PLR developers. Furthermore, the multiple sources of guidance available may add to the problem of inconsistency and lack of uniform standards for the development of PLRs. This highlights the need for harmonization of available or emerging guidance on PLR development, and a move toward more specific guidance for PLRs adapted to the needs of specific audiences. Currently no designated overseer for the quality, timing, or dissemination of PLRs exists, which leaves complete accountability to self-regulation and self-governance; this is a significant gap.

Despite the suggestions included in the guidelines, the limited dissemination options for PLRs were also noted as a barrier [67, 76]. The variable nomenclature of PLRs and the scattered approach to their dissemination have been identified as a barrier to accessibility elsewhere [37]. Overall, this suggests there may be a need for an improved understanding of where patients look for PLRs and adjust dissemination strategies accordingly. Efforts among expert groups to reduce the variability of PLRs nomenclature may help, and specific guidance for search engine optimization of PLRs may also reduce this barrier. The resources required to develop PLRs are a further barrier reported in the literature, however artificial intelligence tools for text generation and review may help reduce this problem in the future [97].

The observations from this scoping review are relevant to English language PLRs only. This reflects the dominance of English language in PLRs and the underlying medical research literature. Translation of PLRs into the audience’s preferred language has been reported elsewhere as an important step in reducing barriers to access and improving trust in healthcare information [98]. Furthermore, audiences who speak different languages may have different patterns of media usage [98]. Therefore, there is a large unmet need, not just for translating PLRs into other languages, but for identifying dissemination channels suitable for non-English-speaking audiences.

Among the literature reporting patient and general public preferences for PLRs, many included small study populations, limiting the generalizability of these observations. The generalizability was further limited as the participants were more educated and more motivated than may be expected in everyday practice [8, 12, 48, 50–52, 64, 68, 89]. Thus, there is a possibility of a fundamental mismatch in health literacy levels and associated knowledge, attitude, and preferences. This leaves an important gap in our knowledge of what truly constitutes the preference of patients and general public audiences when it comes to PLRs on medical research information. Thus, future studies should aim to address this unmet need to understand preferences for PLRs among broader and more diverse populations.

To discuss the implications of our findings on PLRs in enabling SDM, it is pertinent to position them in the context of the core objective of SDM, which is to enable a more inclusive and participatory healthcare ecosystem for patients, where healthcare professions have a critical role in supporting them [7, 94, 99]. In fact, patients are best empowered when provided with individualized information that addresses their preferences and supports their disease management journey [100]. In contrast, low health literacy or inaccessibility of information can reduce patient autonomy, reduce their interest to self-acquire information, and negatively affect their confidence to participate in active discussions with their physicians [101, 102]. In the context of SDM, PLRs, when developed using jargon-free and easy-to-understand language, can emerge as one of the critical enablers in the hands of both patients and healthcare professionals.

The progressively increasing numbers of PLRs across the various medical specialties is reassuring as they fill key knowledge gaps; specialties where information in plain language is still scarce indicate areas with high unmet need and potentially at risk of a spurt in misinformation. The comparatively low number of clinical trial PLRs points at the necessity to address information needs of potential patients who are looking for options beyond commercially available treatments. Albeit a post hoc analysis, nevertheless, the objective reporting of medical research information in the included PLRs is reassuring; this reflects on the potential of PLRs as unbiased sources of reliable information. Our research indicates that there are reliable guidance and best practice documents available for developers of PLRs; however, further harmonization will definitely aid in improving quality and accessibility [94]. While there are also published reports sharing current practices and learnings related to accessibility, readability, data presentation formats, and usability of PLRs, we should perhaps focus more on reports that specifically describe the preferences of patients or the general public and work on alleviating the associated barriers. These practical insights can complement and enhance existing guidance for PLR development and dissemination, thereby enabling health literacy and improving the ability of patients and the general public to participate in SDM.

Strengths and Limitations

We acknowledge several strengths of this analysis. Firstly, this scoping review encompasses a period of five and a half years starting from the period when PLR development started gaining more prominence [15, 16, 103, 104]. To our knowledge, this is the longest timeframe available in published literature. Secondly, it includes all formats of PLRs and supplements knowledge gaps in the current PLR landscape, which is predominantly focused on text-based PLRs. Thirdly, it uniquely captures an in-depth analysis of audience preferences on content and dissemination channels for the first time. Finally, the observations are contextualized uniquely from a health literacy perspective.

The first limitation of our analysis is that the search was limited to the databases and registries included in the scoping review and does not claim to be comprehensive. Secondly, the study population demographics (age, gender) analysis was not performed because a preliminary assessment of the tagging available via PubMed or bibliography databases showed inaccuracies and the manual approach of classification was too cumbersome due to the high volume of literature. Finally, analyses of trends among the PLRs for clinical trials were challenging to interpret, given the modest size of the subset (n = 1078).

Conclusions

This scoping review provides an extensive landscape analysis capturing PLRs. The results have identified evidence gaps that might be a basis for future research and exploration. These results highlight barriers to sharing medical research information with key stakeholders, provide insight into the current formats and channels used to disseminate PLRs, and inform on existing guidance and best practices. We aspire that the results will inform regulators, sponsors, medical societies, journal publishers, and patient organizations about the recommended content standards that apply and the channels that can be used for dissemination of PLRs reporting medical research information. There has been a visible increase in the development and dissemination of PLRs in the years included in our analysis. However, for PLRs to contribute to patient-centric healthcare systems that encourage SDM and to be perceived of value to patients, caregivers, and the general public, they might need to be more accessible and maintain the highest levels of scientific rigor and reliability.

Supplementary Information

Below is the link to the electronic supplementary material.

Declarations

Funding

Open access funding provided by University of Basel. Support for medical editorial and submission assistance was funded by the authors.

Competing Interests

AP is a full-time employee of Novartis Pharma AG. However, this work is independent of his employment and is part of his doctoral research at the Institute for Biomedical Ethics, University of Basel. IA, TW, and BE have no competing interests to disclose.

Availability of Data and Materials

Data can be provided upon reasonable request.

Ethics Approval

Not applicable.

Consent to Participate

Not applicable.

Consent for Publication

Not applicable.

Author Contributions

Avishek Pal: Conceptualization, methodology, formal analysis and investigation, writing—original draft preparation, writing—review and editing writing, resources. Isabelle Arnet: Conceptualization, methodology, writing—review and editing writing, supervision. Tenzin Wangmo: Conceptualization, methodology, formal analysis and investigation, writing—review and editing writing, supervision, resources. Bernice Elger: Conceptualization, methodology, writing—review and editing writing, supervision.