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. 2026 Mar 5;27:295. doi: 10.1186/s13063-026-09556-z

Towards the development of a core outcome set for post-stroke facial palsy (COS post-stroke facial palsy): a study protocol for establishing professional consensus on what to measure

Havva Sumeyye Eroglu 1,4,✉, Audrey Bowen 2,4, Matthew Checketts 3, Claire Mitchell 1,4
PMCID: PMC13069702  PMID: 41782010

Abstract

Background

Facial palsy affects 45–60% of acute stroke patients, significantly impacting their physical function, communication, and quality of life. Varied outcome measures across studies and clinical practices make it difficult to synthesise evidence and establish treatment effectiveness. This protocol describes in detail the professional stakeholder component of a multistage Core Outcome Set (COS) development programme for post-stroke facial palsy. This component focuses on identifying critically important outcomes (the “what” to measure) between two key stakeholder groups: clinicians and researchers.

Methods

This study follows the Core Outcome Set standards for development (COS-STAD) and protocol (COS-STAP) recommendations. The development process consists of five sequential steps: (1) outcome generation through systematic reviews, consultation with our co-researchers who have lived experience, and the findings from qualitative interviews with stroke participants; (2) recruitment of up to 200 international clinicians and researchers (minimum 30 per group) through clinical networks (including professional associations), social media platforms (X, LinkedIn, Bluesky), and via published research identifying stroke and facial palsy researchers; (3) multiple rounds of Delphi surveys; (4) online consensus meeting (at least five per stakeholder group); and (5) results dissemination.

Discussion

This paper reports the detailed protocol for the professional stakeholder component, which will establish consensus among clinicians and researchers on what outcomes are critically important to measure. This protocol addresses a significant gap in stroke rehabilitation research as part of a comprehensive, multi-stage programme to develop a COS for post-stroke facial palsy. Standardising outcome measurement will facilitate more effective synthesis of research findings, reduce research waste, and accelerate intervention development. It describes how people with lived experience have been included from the start and signposts to a parallel study using the supported nominal group technique (detailed protocol reported separately). A parallel systematic review will evaluate available measurement instruments, their psychometric properties to explore “how” to measure the agreed outcome domains. The results of each stage will be disseminated through multiple channels to facilitate widespread research and clinical practice adoption.

Trial registration

Core Outcome Measures in Effectiveness Trials (COMET) registered, December 2024 (https://www.comet-initiative.org/Studies/Details/3295); systematic review registered (PROSPERO), June 2023, CRD42023410768.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-026-09556-z.

Keywords: Stroke, Facial palsy, Core outcome set, Delphi process

Background

Facial palsy is characterised by partial or complete loss of voluntary and involuntary facial muscle control caused by upper or lower motor neuron lesions [1, 2]. Facial palsy due to an upper motor neuron lesion is a common consequence of stroke [3–5], affecting 45–60% of acute stroke patients [6–8]. Facial palsy affects physical appearance, communication, speech, eating, and swallowing [9, 10], having a detrimental impact on stroke survivors’ well-being and quality of life [11].

Systematic reviews on post-stroke facial palsy revealed the use of widely varying outcome measures [5, 12]. While only the Sunnybrook facial grading system has psychometric data for post-stroke facial palsy [13], a variety of measures are used in clinical practice. A recent survey of allied health professionals revealed that informal oromotor examination (40%) and the Sunnybrook Facial Grading Scale (22%) were the most frequently used assessment tools in clinical practice, with additional varied measures including the Facial Disability Index, Facial Clinimetric Evaluation Scale, and EQ-5D-5L [3]. This heterogeneity in outcome measurement makes it difficult to synthesise evidence and establish treatment effectiveness, thereby hindering meaningful comparison of interventions and contributing to research waste [12, 14].

A Core Outcome Set (COS) is defined as a standardised set of outcomes that should be measured and reported, as a minimum, in all studies for a specific health condition [15]. The importance of developing such standardised outcome sets has been highlighted across various clinical fields [16–18]. The development of a COS for post-stroke facial palsy would enable the combination and comparison of findings across studies, reduce reporting bias, and ensure that collected data are both useful and usable. This standardisation can help clinicians and researchers to understand what outcomes are important to measure in clinical practice and research.

The development of a COS for post-stroke facial palsy is a multi-stage, overarching programme of work involving multiple stakeholder groups and methodological approaches. The aim of this paper is to report the protocol for the development of an international consensus-based COS for post-stroke facial palsy, focusing on identifying what should be measured in research from the perspective of two of the three key stakeholder groups, researchers, and healthcare professionals. These two groups have specialist knowledge of outcome use, interpretation, and feasibility in research and clinical contexts. They are well placed to identify relevant outcome domains based on their experience of selecting, using, and evaluating outcomes across existing research and clinical practice. The third stakeholder group, people with lived experience, should be included from the outset. As part of this, a parallel study with stroke survivors using the supported nominal group technique will be reported separately to ensure a detailed description of accessible, rigorous participation methods. The voice of the lived experience group plays an important role in identifying key outcomes for research, and this perspective often differs from or complements that of academic researchers and other stakeholders [19]. Evidence demonstrates that outcomes identified as important by people with lived experience are often not found in the clinical literature [20]. People with lived experience have shown preferences for self-reported outcomes that capture their lived reality, which may differ from outcomes prioritised by clinicians [19, 20]. This underscores why lived experience input must be captured as core data throughout the COS development process. The subsequent step of determining how these outcomes should be measured will be addressed through our systematic review.

Study objectives

Overall COS development programme objective

To develop an international consensus-based COS for post-stroke facial palsy research through a multi-stage programme involving professional stakeholders and people with lived experience.

Objectives for this professional stakeholder component

The primary objective of this paper is to describe methods for reaching an international consensus among clinicians and researchers on what outcome domains should be measured in post-stroke facial palsy research.

Specific objectives include the following:

  1. To identify a comprehensive long list of possible outcome domains.

  2. To achieve international consensus on what outcomes are considered critically important to measure among clinicians and researchers.

This protocol focuses on the long list generation and Delphi study with professional stakeholders. A separate protocol will address the parallel study with people with lived experience using nominal group technique, and a protocol of our systematic review of measurement instruments has been registered on PROSPERO (CRD42023410768).

Principal Research Question:

What are the most important outcomes to measure for people with post-stroke facial palsy, as determined by international consensus among clinicians and researchers?

Methods

This protocol was developed in accordance with two key methodological frameworks: the Core Outcome Set standards for development (COS-STAD) recommendations, the Core Outcome Set standardised protocol (COS-STAP) checklist and Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) reporting guidelines [21–23]. The completed COS-STAP and SPIRIT checklists are provided as supplementary documents (Additional file 1 and Additional file 2, respectively).

Scope

This initial phase of COS development addresses facial palsy occurring after stroke in adults (aged ≥ 18 years), regardless of stroke type or time since onset. The COS will be applicable across all intervention types. While primarily intended for research applications (clinical trials, observational studies, and systematic reviews), the translation of COS to clinical practice presents distinct implementation challenges, with evidence suggesting variable uptake and impact across different healthcare settings [24].

Ethics and consent

Research ethics approval was obtained from the University of Manchester (reference 2024–21316-38,685).

Informed consent will be obtained for participation using different approaches appropriate to each study component. For the e-Delphi surveys, informed consent will be obtained through an explicit consent process on the first page of the online survey: participants will be directed to read the participant information sheet via a provided link and must actively select “yes” to confirm they have read and understood the information and consent to proceed with the survey. This digital consent process ensures informed participation while being appropriate for the online survey format. Written consent will be obtained from the subset participating in the consensus meeting.

Study design

This initial phase to develop a COS for post-stroke facial palsy has been developed using a multiple-method design incorporating a modified Delphi process with online surveys and consensus meetings, as illustrated in Fig. 1. The study will be conducted online, allowing for international participation without geographical restrictions from healthcare professionals and researchers recruited through various clinical networks, research collaborations, and professional associations worldwide. The modified Delphi process methodology has been chosen to establish consensus among two key groups of stakeholders, clinicians and researchers. The development process consists of five sequential steps, which are described in detail below: outcome generation and recruitment, followed by Delphi survey rounds, consensus meeting, and dissemination of results.

Fig. 1.

Fig. 1

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Workflow for the initial phase of developing the COS study process

This approach follows the Cochrane Skin–Core Outcome Set Initiative (CS-COUSIN) roadmap, a framework for developing core sets of outcomes and measurements [25]. While this framework was originally developed for dermatology research, its methodological principles are applicable across clinical conditions, and we have adapted its systematic approach by tailoring the scope, stakeholder groups, and outcome processes to suit the specific context of post-stroke facial palsy research.

Step-1: generation of outcomes

The initial phase of developing our COS for post-stroke facial palsy involves creating a comprehensive long list of potential outcome domains through multiple sources. We will include outcomes that were used in efficacy and effectiveness trials included in existing systematic reviews of post-stroke facial palsy [5, 12], and we will update these searches to ensure that more recent trials are also captured.

To ensure the inclusion of patient-relevant outcomes, we will work closely with a stroke survivor lived experience (patient and public involvement, PPI) group. This group comprises stroke survivors with experience of post-stroke facial palsy who have been involved in our wider programme of work and have experience of developing other core outcome sets. Our approach to PPI follows established principles for meaningful patient involvement in research [26], ensuring stroke survivors contribute substantively to outcome identification and framing rather than simply reviewing researcher-generated lists. This is essential for capturing outcomes reflecting life impact [27].

At the earliest stage of this project, before the Delphi surveys are launched, the PPI group will: (a) review the preliminary list of outcomes identified from the systematic reviews, (b) consider the early findings from planned qualitative interviews to explore impact and what is important to people with facial palsy after stroke, (c) identify missing concepts and propose additional outcomes that reflect any other priorities, and (d) advise on the wording and framing of outcomes to ensure they are understandable and meaningful to stroke survivors. This pre-Delphi work ensures that patient-identified outcomes, patient language, and patient perspectives on outcome importance inform the professional Delphi process and contents [28]. Feedback from the PPI group will be discussed by the study team and incorporated into a revised long list of potential outcome domains, which will form the basis of the Delphi survey for clinicians and researchers. In parallel, stroke research colleagues will be consulted to check for any further outcomes domains that may have been overlooked. The consolidated long list will then be systematically categorised according to the International Classification of Functioning, Disability and Health (ICF) framework [29], organising outcome domains into distinct levels: body structures and functions, activity, participation, and wellbeing/quality of life.

Step-2: recruitment

This study will target two stakeholder groups with the following inclusion criteria: (1) researchers who are or who have been involved in stroke or facial palsy related research, (2) healthcare professionals with experience of working with patients who have post-stroke facial palsy. The recruitment process will extend internationally to maximise the breadth and depth of professional input. While healthcare professionals from all disciplines are eligible, we anticipate higher representation from speech and language therapists and physiotherapists, as these professionals are typically most involved in the direct management of post-stroke facial palsy [30]. The study aims to recruit a diverse group of professionals across various geographical regions and professional backgrounds, with varied expertise in facial palsy research and clinical practice, to ensure comprehensive insights into what is important to measure for people living with post-stroke facial palsy. Participants will complete the survey online, which includes both demographic questions (e.g. professional background, years of experience) and the Delphi outcome rating questions, at a time convenient for them.

There is no universally agreed optimal number of participants for a Delphi study, and sample sizes can vary widely [31]. We aim to recruit up to 200 participants across two stakeholder groups: 100 clinicians and 100 researchers. Our minimum target is 30 participants per group, which aligns with previous COS studies [32]. We expect that at least 13 participants from each group will complete the final round of the Delphi survey, consistent with other COS developments [33]. Participants will be sent the participant information, confirm they have read this, and give consent to continue to the online survey; all personal data will be stored securely and pseudonymised.

We intend to recruit healthcare professionals from various clinical networks of healthcare professionals working in facial palsy and stroke, including professional associations across rehabilitation, neurology, physiotherapy, speech and language therapy, occupational therapy, orthoptics, nursing, medicine, and psychology (e.g. Facial Therapy Specialists International, World Federation for NeuroRehabilitation, World Stroke Organization, Association of Chartered Physiotherapists Interested in Neurology, International Orthoptic Association, Psychological Society of Ireland, Swedish Association of Occupational Therapists, Federazione Logopedisti Italiani, British and Irish Association of Stroke Physicians, National Stroke Nursing Forum). We will also advertise the study via our dedicated study accounts on social media platforms (X and Bluesky) and through posts on study team members’ LinkedIn profiles. For researcher recruitment, we will contact researchers identified through systematic reviews of post-stroke facial palsy and other published studies [5, 12, 34–36]. In addition, we will use our study accounts on X and Bluesky and study team members’ LinkedIn profiles to share the recruitment invitation. While some researchers may also be healthcare professionals, in this study we are categorising “researchers” as those primarily engaged in academic or research activities, as distinct from those participating primarily in a clinical capacity. Demographic data will be collected in the survey allowing participants to indicate whether they identify as a researcher, clinician, or both.

The first round of Delphi survey participant recruitment has commenced. At the time of protocol submission, participant recruitment and data collection are actively ongoing. If recruitment targets are not met, the recruitment period may be extended. The consensus meeting will begin after the completion of the Delphi survey rounds.

Step-3: delphi survey

Using the outcomes identified during Step 1, participants will complete the first round of the online Delphi survey by rating the importance of each outcome on a 1–9 scale (1 = least important, 9 = most important).

Rankings of 7–9 indicate critical importance, 4–6 outcomes that are important but not critical, whilst ratings of 1–3 are of limited importance using the Grading of Recommendations Assessment, Development, and Evaluations (GRADE) scale [37].

To minimise the impact of missing data, questions within each domain will be presented in random order for each participant, consistent with evidence showing the influence of question order in outcome prioritisation [38].

The consensus criteria for including or excluding outcomes in the COS for post-stroke facial palsy will be predefined. An outcome will be considered to have reached “consensus in” (of the COS) when 70% or more of participants in each stakeholder group rate it as critically important (scoring 7–9) and fewer than 15% rate it as having limited importance (scoring 1–3). Conversely, an outcome will be considered to have reached “consensus out” when 50% or fewer participants in each stakeholder group rate it as critically important (scoring 7–9). All outcomes that are clearly “consensus in” or “consensus out” from the survey will be briefly ratified during the consensus meeting. The outcomes with no clear consensus either way from the survey will be discussed in more detail at the consensus meetings. This definition ensures that the COS includes outcomes that are consistently rated as highly important across all stakeholder groups while excluding those with limited perceived importance.

Participants will be invited to suggest additional outcomes that they consider important but had not been included in the round 1 Delphi survey. These newly suggested outcomes will be reviewed by the study team. The team will discuss each suggestion in detail to determine whether it is already captured by an existing outcome domain or represents a genuinely new outcome. Where suggestions are not adequately covered by existing outcomes, they will be added to round 2 of the Delphi survey for participant rating. After completing round 1, all responses will be analysed to assess differences in priority. All completed outcome ratings will be analysed anonymously according to each stakeholder group. If a participant rated some outcomes but did not complete the survey, their available ratings will be included in the analysis. However, completely blank responses will be excluded. If 90% or above of both stakeholder groups rate any outcomes as either 7–9 critically important or 1–3 limited importance, these will be removed from round 2 of the survey but will still be ratified or discussed in the consensus meeting as appropriate. Participants will be informed of any changes to the survey. In addition, we will consider comments from participants completing round 1, which may involve adding new outcomes or removing others.

The survey will include basic demographic questions (gender, ethnicity, country of residence, and duration of professional experience) along with the main survey questions. These demographic data will be collected to characterise the diversity and representativeness of our participant sample.

In round 2 of the Delphi process, participants will see the percentage distribution of scores from both stakeholder groups and their own previous ratings. In keeping with Delphi methodology principles, participants will only be presented with anonymised, aggregated responses during subsequent survey rounds [39]. Participants will be notified of any modifications made based on round 1 feedback. After reviewing this feedback, participants will be asked to re-rate relevant outcomes, considering both their initial response and the collective responses from all stakeholder groups. Participants will again have the opportunity to suggest additional outcomes, as in round 1, which, if appropriate, will be included for rating if we proceed to round 3.

If after round 2, there are clear discrepancies between the two groups where one group is strongly “consensus in” or “consensus out” and this is the direct opposite of the other group, a third round of the survey might be appropriate. This additional round will follow the same format as round 2, with participants viewing the updated group responses and their previous ratings before re-rating these remaining outcomes. Ethics approval is in place for this potential additional round if required.

All survey rounds will be conducted online via Qualtrics and will remain open for 4–6 weeks each. If participation rates are low, emails will be sent to the various networks to encourage participation. If subsequent survey response rates are low, then participants will be sent reminders at the end of week 2 to complete the survey at the email addresses they registered in round 1 [40]. The responses from healthcare professionals and researchers will be analysed separately to identify any differences in priorities.

At the end of each round, participants will be asked to provide their email addresses to allow us to invite them to the subsequent Delphi survey rounds and the consensus meeting. Contact information will be stored separately and securely from survey responses in accordance with data protection regulations and to ensure anonymised analysis.

Step-4: consensus meeting

Following the Delphi rounds, an online consensus meeting will be held to review survey results and establish agreement on the COS. To ensure effective group discussion, participation will be limited to 10 participants from each stakeholder group (with at least five participants per group), purposively selected from those who completed all Delphi rounds to maintain a balanced representation of both stakeholder groups (approximately equal numbers of researchers and clinicians) and geographical regions. All participants will be required to provide written consent and verify their professional credentials prior to participation. The consensus meeting will be conducted via Microsoft Teams, a secure video conferencing platform. Participants will be asked to briefly identify themselves at the start of the meeting but will have the option to turn off their video thereafter. The meeting will be recorded on an encrypted device for data analysis purposes, with recordings deleted following analysis. Voting will be conducted anonymously within Microsoft Teams using yes/no polls, and the results of each vote will be securely recorded for analysis.

The meeting will be led by an independent facilitator who will present the results from all Delphi rounds according to the predefined consensus criteria.

For outcomes that were voted by both groups as “consensus out” during the Delphi rounds, the facilitator will briefly ask if anyone has compelling reasons to re-visit any of these items. If not, these outcomes will be ratified, then excluded. If participants express doubts, a structured discussion will be held to allow views to be shared among the group. Following the discussion, the outcome will be taken forward to a yes/no vote. Outcomes receiving less than 70% “yes” votes will be excluded, while those reaching the 70% threshold will be included in the final COS for post-stroke facial palsy.

For outcomes that reached “consensus in” during the survey, they would then be discussed as to whether they are still considered critically important to be included in the COS post-stroke facial palsy. Voting would have to reach the 70% threshold of “yes” votes required for inclusion in the COS.

For outcomes that did not reach either “consensus in” or “consensus out”, there would need to be more detailed discussion in the meeting, and this discussion would help the participants in the consensus meeting decide which way to vote. All participants will then vote on whether each outcome should be included (“yes”) or excluded (“no”) from the COS, with a 70% threshold of “yes” votes required for inclusion in the COS.

Step-5: dissemination

We will adopt a multi-method approach to dissemination of this first stage to develop a COS-post stroke facial palsy. Reporting will follow the COS-STAR (Core Outcome Set-STandards for Reporting) guidelines [40]. The initial findings for the post-stroke facial palsy COS will be published in an open-access journal, presented at conferences, and shared through professional networks (e.g. special interest groups and clinical excellence networks) to maximise reach among researchers and clinicians. To ensure accessibility for people with lived experience, we will also disseminate results via meetings with stroke survivors, our PPI group, stroke charities, support organisations, and online platforms, using formats such as plain language summaries and infographics. After publication, our initial COS for post-stroke facial palsy will be available on the Core Outcome Measures in Effectiveness Trials (COMET) database and has already been registered with COMET (https://www.comet-initiative.org/Studies/Details/3295).

Discussion

This protocol outlines our methods for the professional stakeholder component of a multi-stage programme to develop a COS for post-stroke facial palsy. Our approach includes online Delphi surveys for initial agreement followed by a consensus meeting for final decision-making to agree what is critically important to measure in post-stroke facial palsy according to two of the three key stakeholder groups, researchers and clinicians working in this area. Throughout this process, we will strictly adhere to published standards for core outcome development in stroke and facial palsy research and follow established methodological guidance [21, 40].

This starting point of COS development addresses a critical gap in stroke and facial palsy rehabilitation research. A final standardised outcome set will facilitate several important advances in the field. First, it will enable more effective synthesis of future research findings, allowing for meaningful comparisons across studies. Second, it will optimise resource allocation in research by ensuring that essential outcomes are consistently measured; or where relevant measurement instruments do not exist, it will indicate a need for this development. These improvements will ultimately accelerate the development and evaluation of intervention approaches for facial palsy management.

Our systematic and structured approach includes multiple steps. Through this initial step of the work, we will establish preliminary core outcome domains through a comprehensive literature review and expert consultation with healthcare professionals and researchers, front-loaded by input from people with lived experience through qualitative interviews and Patient and Public Involvement [26].

People with lived experience (stroke survivors) are core stakeholders in this COS development programme. Rather than join this Delphi process, their participation in rating and reaching consensus on outcome domains requires different, more inclusive methodology to ensure accessible and supported participation. Many stroke survivors experience communication difficulties, cognitive changes, or fatigue, which necessitate careful methodological planning. A parallel study with stroke survivors using a supported nominal group technique is planned and will be reported in a separate, dedicated protocol paper. Nominal group technique is particularly appropriate for people with communication difficulties as its structured, turn-taking format supports equal participation and allows time for communication facilitation [41]. This approach ensures that lived-experience perspectives are captured using rigorous, appropriate methods with accessible materials and appropriate support for communication and participation.

In parallel, we are conducting a systematic review of outcome measures, which will provide crucial information about what measures are available that fit the agreed domains, their psychometric data, and clinical utility/practical implementation. This will help evaluate and recommend appropriate measurement instruments for each outcome and inform the future development of a core measurement set (completing the “what” to measure and the “how” to measure it).

Trial status

This protocol (version 8.0, dated February 14, 2025) describes the development of a COS that is ongoing. The first round of Delphi is January–February 2025, the second round is April 2025, the third round (if necessary) is May 2025, and consensus meetings are June 2025.

Supplementary Information

13063_2026_9556_MOESM1_ESM.docx (35.5KB, docx)

Supplementary file1. SPIRIT 2025 checklist (DOCX 35.5 KB)

13063_2026_9556_MOESM2_ESM.docx (20KB, docx)

Supplementary file2. COS-STAP statement checklist (DOCX 20.0 KB)

Acknowledgements

The authors thank the participants. HSE would like to acknowledge the Republic of Turkey Ministry of National Education for providing financial support.

Abbreviations

COS

Core Outcome Set

COMET

Core Outcome Measures in Effectiveness Trials

COS-STAP

Core Outcome Set-Standardised Protocol Items

COS-STAD

Core Outcome Set standards for development recommendations

COS-STAR

Core Outcome Set-Standards for Reporting guidelines

CS-COUSIN

Cochrane Skin – Core Outcome Set Initiative

SPIRIT

Standard Protocol Items: Recommendations for Interventional Trials

PPI

Patient and public involvement

ICF

International Classification of Functioning, Disability and Health

Authors’ contributions

HSE is the Chief Investigator; she conceived the study and led proposal and protocol development. AB, MC, and CM contributed to study design and to the development of the proposal. HSE wrote the first draft. All authors read and commented on the paper, and they read and approved the final manuscript.

Funding

This study has not received specific project funding; however, it is part of HSE’s PhD. The latter is funded by the Republic of Turkey Ministry of National Education, and some of CM’s PhD supervision time is funded by a personal postdoctoral fellowship from the Stroke Association (https://www.stroke.org.uk/) SA_PDF_21\100017.

Data availability

Anonymised data from this study will be available on reasonable request up to 5 years in accordance with our ethics approval. Requests should be directed to the corresponding author (havvasumeyye.eroglu@postgrad.manchester.ac.uk) or to Claire Mitchell (claire.mitchell@manchester.ac.uk).

Declarations

Ethics approval and consent to participate

Ethics approval was granted by the University of Manchester Ethics Committee 2024–21316-38,685. Informed consent will be obtained for participation. Participation in the e-Delphi surveys will be considered to imply consent for participation once they have read the participant information sheet, with no written consent required. Information about the Delphi survey will be given in the initial pages of the online survey. Written consent will be obtained for the consensus meeting.

Consent for publication

Not applicable

Conflict of interests

The authors declare that they have no competing interests.

Footnotes

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

13063_2026_9556_MOESM1_ESM.docx (35.5KB, docx)

Supplementary file1. SPIRIT 2025 checklist (DOCX 35.5 KB)

13063_2026_9556_MOESM2_ESM.docx (20KB, docx)

Supplementary file2. COS-STAP statement checklist (DOCX 20.0 KB)

Data Availability Statement

Anonymised data from this study will be available on reasonable request up to 5 years in accordance with our ethics approval. Requests should be directed to the corresponding author (havvasumeyye.eroglu@postgrad.manchester.ac.uk) or to Claire Mitchell (claire.mitchell@manchester.ac.uk).

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