Care (Education) and Treatment Reviews (C(E)TRs) are intended to reduce unnecessary psychiatric hospital admission and length of stay for people with intellectual disability and autistic people. The use and impact of C(E)TRs have not been systematically evaluated since their introduction in England in 2015. The aims of this study are to describe the demographic and clinical profiles of people who receive a community C(E)TR and to investigate their effects on admission, length of hospital stay and clinical and functional change.

We will conduct a retrospective cohort study using de-identified data from electronic health records derived from two large National Health Service mental health providers in London, England, including one replication site. Data will be extracted using the Clinical Record Interactive Search (CRIS) tool for all people with recorded intellectual disability and/or autism who received mental healthcare from 2015. We will identify community C(E)TR events using keyword searches. Community C(E)TRs will be examined in two ways: (1) In a community cohort, we will capture data in the 6-month periods before and after a community C(E)TR and compare this to a matched control group and (2) In a hospital cohort, we will compare groups who did and did not receive a community C(E)TR prior to their admission. We will describe the socio-demographic and clinical profiles of each group and their health service use, and compare C(E)TR and no C(E)TR groups using t-tests (or a non-parametric equivalent). The primary outcomes are admission to a psychiatric hospital (community cohort) and length of psychiatric hospital admission and clinical change (hospital cohort). Admission to psychiatric hospital will be estimated using propensity score weighting and difference-in-differences methods. Cox’s proportional hazard model will be used for length of hospital admission and repeated-measures analysis of variance (ANOVA) will be used to assess clinical change.

Use of CRIS to examine de-identified clinical data for research purposes has overarching ethical approval. This study has been granted local approval by the South London and Maudsley CRIS Oversight Committee. Findings will be disseminated in an open-access peer-reviewed academic publication, at conference presentations, and to service users and carers in accessible formats.

This study aims to assess the feasibility of respondent-driven sampling (RDS) to recruit participants with recent abortion experiences in humanitarian contexts, and describe the composition of the study sample generated with this sampling method.

This was a three-phase mixed-methods community-engaged research study employing an exploratory and explanatory sequential approach. We conducted in-depth interviews, focus group discussions, an interviewer-administered questionnaire on abortion experiences and a health facility assessment.

Bidibidi Refugee Settlement, Uganda and Kakuma Refugee Camp, Kenya from November 2021 to December 2022.

Using RDS, we recruited 600 participants in Kakuma and 601 participants in Bidibidi with recent abortion experiences. In Kakuma, participants were primarily from Burundi, the Democratic Republic of the Congo and South Sudan; participants in Bidibidi were primarily from South Sudan. Most participants in both sites had completed at least some primary school and were not employed.

RDS recruitment dynamics: convergence and bottlenecks on key sociodemographic variables, recruitment and population homophily, reciprocity of social ties, success and experiences recruiting.

There were minor violations of RDS assumptions, particularly regarding assumptions of reciprocity of ties and seed composition independent of sample. In addition, there was a strong tendency of participants to recruit those from the same home country and living within the same camp zone. However, sample proportions for age, home country, marital status, zone of residence and student status reached equilibrium (stabilised) by around 500 participants at each site, and we were able to quickly attain the study sample size.

While the true representativeness of our sample remains unknown, RDS is a practical and effective recruitment method in humanitarian contexts for sensitive topics, particularly for research questions in which no data or sampling frames exist. However, attention to representativeness and community engagement is essential to optimising its application and ensuring success.

Influenza is a major global health concern, responsible for up to 650 000 respiratory-related deaths annually. Although influenza is often perceived as mild in healthy adults, it can cause severe outcomes in high-risk groups, such as older adults, young children, pregnant women and those with underlying medical conditions. Various clinical, sociodemographic and environmental factors influence the progression to severe outcomes, whereas resilience factors, such as vaccination, may reduce risks. Despite growing research, the evidence base regarding risk and resilience is spread across many different aspects of the literature. This umbrella review will synthesise evidence from existing systematic reviews and meta-analyses to identify key risk and resilience factors associated with the progression of influenza to severe outcomes in the general population.

This umbrella review follows the Joanna Briggs Institute (JBI) and Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines. We will include systematic reviews and meta-analyses reporting host-related risk or resilience factors for severe influenza outcomes. Four databases (EMBASE, Scopus, Medline and CINAHL) will be searched for English-language publications. Study quality will be assessed using AMSTAR 2, and the body of evidence will be evaluated using Grading of Recommendations Assessment, Development and Evaluation. Due to heterogeneity, findings will be analysed narratively. Risk and resilience factors will be grouped into demographic, clinical, behavioural, social and psychological domains.

No ethical approval is required. The completed review will be shared through peer-reviewed journals and conference presentations.

CRD420250644475.

The Quadrivalent human papillomavirus (HPV) Vaccine Evaluation Study with Addition of the Nonavalent Vaccine Study (QUEST-ADVANCE) aims to provide insight into the long-term immunogenicity and effectiveness of one, two and three HPV vaccine doses. Here, we describe the protocol for QUEST-ADVANCE.

QUEST-ADVANCE is an observational cohort study including males and females who are unvaccinated or vaccinated with the quadrivalent or nonavalent HPV vaccine in British Columbia, Canada. Female participants who are unvaccinated or vaccinated with 1–3 doses of the quadrivalent or nonavalent HPV vaccine at 9–14 years of age will be recruited approximately 5 or 12 years postvaccination eligibility. Male participants who are unvaccinated or vaccinated with 1 or 2 doses of the nonavalent HPV vaccine at 9–14 years of age will be recruited at approximately 5 years postvaccination eligibility. The study involves a maximum of four visits over a period of 4–5 years for female participants, and two visits over a 12-month period for male participants. At each visit, self-collected swabs (cervico-vaginal or penile) and questionnaire data will be collected. In each study group, a subset of participants will be invited to participate in a substudy evaluating the long-term humoral immunogenicity of the HPV vaccine. Additional blood samples will be collected from participants who are part of the immunogenicity substudy. The total required sample size is 7180 individuals. The primary objectives are (1) to examine vaccine effectiveness in males and females against prevalent genital HPV infections for one, two and three doses of the HPV vaccine compared with unvaccinated participants and (2) to evaluate if there is non-inferior immunogenicity as indicated by type-specific antibody response of one dose of the HPV vaccine in 20–27-year-old females vaccinated at 9–14 years of age compared with historical data of three doses of the HPV vaccine females vaccinated at 16–26 years of age up to 12 years postvaccination.

QUEST-ADVANCE was approved by the Research Ethics Board of the University of British Columbia/Children’s and Women’s Health Centre of British Columbia (H20-02111). Individual electronic informed consent or assent will be obtained from each participant before any study-specific procedures are undertaken. Results will be published in an international peer-reviewed journal and on the study website.

Lower gastrointestinal symptoms attributed to colorectal disease are common. Early diagnosis of serious colorectal disease such as colorectal cancer (CRC), precancerous growths (polyps) and inflammation is important to ensure the best possible outcomes for a patient. The current ‘gold standard’ diagnostic test is colonoscopy. Colonoscopy is an invasive procedure. Some people struggle to cope with it and require intravenous sedation and/or analgesia. It is also resource-intensive, needing to be performed in specialist endoscopy units by a trained team. Across the UK, the demand for colonoscopy is outstripping capacity and the diagnosis of colorectal disease is being delayed. A colon capsule endoscope (CCE) is an alternative colorectal diagnostic. It is a ‘camera in a pill’ that can be swallowed and which passes through the gastrointestinal tract, obtaining visual images on the colon. There is now established experience of CCE in the UK. CCE might provide a less invasive method to diagnose colorectal disease if found to be accurate and effective and provide a means by which to increase the National Health Service (NHS) diagnostic capacity.

The aim of this study is to determine the diagnostic accuracy of CCE when compared with colonoscopy in representative and clinically meaningful cohorts of patients. An evaluation of the experiences of CCE for the patient and clinical team and an assessment of cost effectiveness will be undertaken.

We will undertake three research workstreams (WS). In WS1, we shall perform a paired (back-to-back) study. Each participant will swallow the CCE and then later on the same day they will have a colonoscopy. The study has been designed in collaboration with our Patient Advisory Group and as closely mirrors standard care as is possible. 973 participants will be recruited from three representative clinical contexts; suspected CRC, suspected inflammatory bowel disease and postpolypectomy surveillance. Up to 30 sites across the UK will be involved to maximise inclusivity. Measures of diagnostic accuracy will be reported along with CCE completion rates, number of colonoscopy procedures potentially prevented and adverse events, such as capsule retention. A nested substudy of intraobserver and interobserver agreement will be performed. WS2 will develop models of cost-effectiveness and WS3 will evaluate the patient and clinician experience, with reference to acceptability and choice.

The study findings will provide the evidence base to inform future colorectal diagnostic services.

The study has approval from the North East—Tyne and Wear South research ethics committee (REC reference 24/NE/0178, IRAS 331349). The findings will be disseminated to the NHS, National Institute for Health and Care Excellence, other clinical stakeholders and participants, patients and the public.

ISRCTN16126290.

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) entails substantial morbidity and mortality, yet no epidemiologic evidence exists on its outcomes in Mexico. This study assessed national hospitalisations (2005–2022) and mortality (2000–2022) related to AAV using data from the General Board of Health Information.

Retrospective, population-based time-trend analysis on administrative health data.

Mexico’s national hospital discharge and mortality registries, covering 1 January 2000 through 31 December 2022.

All individuals aged ≥ 15 years with a primary or secondary International Classification of Diseases, 10th revision, diagnosis of AAV recorded during hospitalisation or on death certificates nationwide.

The study’s primary outcomes were the age-standardised hospitalisation and mortality rates for AAV (expressed per 100 000 population, overall and by sex), with temporal trends in both rates quantified using Joinpoint regression to calculate annual percent change (APC) and average APC (AAPC).

We identified 2804 hospitalisations and 599 deaths. Females accounted for 49.7% of hospitalisations, while males represented 48.7% of deaths. Although the overall age-standardised hospitalisation rate (ASHR) and mortality rate (ASMR) AAPCs were not statistically significant, relevant trends emerged. From 2010 to 2022, ASHR declined significantly (APC: –5.2%; 95% CI –9.7, –0.5; p=0.03), whereas mortality rates remained stable from 2000 to 2022 (AAPC: +3%; 95% CI –4.6, 11.3; p=0.45). Nevertheless, mortality increased among males (APC: +6.4%; 95% CI 0.9, 12.2; p=0.02) and individuals over 45 years (APC: +8.6%; 95% CI 1.7, 16.0; p=0.02) from 2008 onwards.

Overall, these findings indicate no major changes in national rates but reveal a decline in hospitalisations since 2010 and a rise in mortality for specific subgroups since 2008. Targeted interventions, particularly for older adults and men, appear warranted to address this evolving disease burden. Future research should explore underlying risk factors and evaluate tailored strategies to improve clinical outcomes in AAV across Mexico.

To quantify and describe the use of real-world data (RWD) in National Institute for Health and Care Excellence (NICE) oncology technology appraisal (TA) final appraisal determination documents.

A systematic literature review was conducted on pharmaceutical NICE oncology TAs published between April 2000 and March 2024 (covering financial years 2000/2001 to 2023/2024 inclusive) extracted on 22 August 2023 (2000/2001 - 2022/2023) and 8 August 2024 (2023/2024).

NICE TA final appraisal determination documents.

All pharmaceutical oncology TAs published between April 2000 and March 2024 (financial years 2000/2001 to 2023/2024) that did not go on to be terminated.

The data required for eligibility screening was extracted from an Excel file directly from the NICE website, where data related to each TA was extracted using an automated script derived from published sources. TAs were assessed based on prespecified review criteria covering whether an RWD submission was reported by the committee, and if so, which RWD sources were used, alongside the methods reported and any feedback from the committee regarding the use of RWD. Bias was not assessed as part of the study.

Of 310 TAs identified, 135 (48.0%) used RWD. A variety of RWD types were used, mostly from UK or US data sources. 47 TAs (34.8%) leveraged RWD from multiple sources. RWD was mostly used in comparisons of survival (41.5%), to inform utility values (26.7%) and to compare baseline characteristics (19.3%), with matched adjusted indirect comparisons (MAICs) and external control arms (ECAs), seen from 2015 and 2018, respectively. The committee expressed concerns around the RWD presented by the company in 53 TAs (39.2%), the most common being a lack of generalisability to the UK population and/or National Health Service practice and comprehensiveness of the RWD.

This study quantifies the increasing use of diverse RWD sources in NICE oncology TAs, as well as the shift towards more complex methods like MAICs and ECAs. The feedback of the NICE committee highlights key areas of improvement as the generalisability and maturity of the RWD presented.

Sepsis and antibiotic resistance constitute a deadly synergy, causing the loss of millions of lives across the world, with their economic and developmental consequences posing a threat to global prosperity. Their impact is disproportionately felt in resource-limited settings and among vulnerable populations, especially children. A key challenge is prompt diagnosis and timely commencement of appropriate antibiotic therapies. These challenges are compounded in low-income and middle-income countries by a lack of comprehensive epidemiological data, with Nigeria being one such country for which it is lacking. Kaduna is the third largest state in Nigeria, with over 10 million inhabitants, of whom more than half are children under 14 years old. While bacterial sepsis and antimicrobial resistance (AMR) are recognised as a growing problem in the state, there are huge gaps in the current understanding of their aetiology. This project employs a cross-sectional design to investigate the clinical and haematological markers of paediatric sepsis, alongside determining the bacterial cause and prevalence of AMR at four high-turnover hospitals in Kaduna State, Nigeria. Further, whole-genome sequencing of isolated bacterial pathogens will be performed to determine the genetic features of resistance. This project represents the largest surveillance study of paediatric sepsis in Kaduna to date. Additionally, we aim to use the clinical, haematological, microbiological and genomic data to derive predictive models for sepsis causes, treatment strategies and patient outcomes.

This is a hospital-based, cross-sectional study that will recruit up to 461 children with bacterial sepsis who were admitted at the two teaching and two general hospitals in Kaduna State, Nigeria. Children presenting with features of fever, subnormal temperature and body weakness would be recruited into the study and have their blood samples collected. The blood samples will be used for culture, complete blood count, HIV and malaria testing. Accordingly, we will capture clinical presentation, haematological characteristics, causative pathogen from blood culture and patient outcomes. Nutritional status, known congenital immunosuppressive diseases, HIV infection and malaria infection will also be determined and documented. The bacterial isolates will be phenotypically characterised for AMR and genotypically following whole genome sequencing. Known and potential confounders to the outcomes of bacterial sepsis would be assessed in all participants, and adjustment for confounding would be performed using logistic regression and/or stratification±Mantel-Haenszel estimator where applicable.

Ethical approvals were granted by the University of Birmingham (ERN_2115-Jun2024), the Ahmadu Bello University Teaching Hospital (ABUTHZ/HREC/H45/2023), Barau Dikko Teaching Hospital, Kaduna (NHREC/30/11/21A) and the Kaduna State Ministry of Health (MOH/AD M/744/VOL.1/1110018). The study will be conducted using the international guidelines for good clinical practice and based on the principles of the Declaration of Helsinki. The results will be disseminated via oral and poster presentations in scientific conferences and published in peer-reviewed journal articles.

The COVID-19 pandemic led to major disruptions in society across many spheres, including healthcare, the economy and social behaviours. While early predictions warned of an increased risk of suicide during and after the COVID-19 pandemic, rates of suicide deaths remained stable or decreased over that period for most countries. In contrast, the prevalence of suicidal ideation doubled and suicide attempts slightly increased during the COVID-19 pandemic in the adult general population worldwide, accompanied by a higher prevalence of major depressive disorder and anxiety disorders. While these data can tell us what happened, they cannot tell us why. Qualitative suicide research seeks to understand experiences of individuals with suicide-related thoughts and behaviours, provides an in-depth exploration of their lives and interactions with others and centres their views and unique context. There is little qualitative research focusing on suicidality during the pandemic. This study will use a qualitative approach to explore the extent and impact of the COVID-19 pandemic on Canadians who experienced suicidality and review their experiences of accessing mental healthcare to identify key components in supporting safety and recovery.

This study will involve approximately 100 semistructured interviews with participants across four Canadian provinces and will explore experiences with suicide-related thoughts and behaviours during the COVID-19 pandemic. Transcripts will be analysed through qualitative analysis informed by constructivist grounded theory.

The study was approved by the Research Ethics Board of the Centre for Addiction and Mental Health, Toronto Academic Health Sciences Network (for JZ: CAMH REB No 104-2022). In addition to traditional peer-reviewed presentations and publications, a report will make study findings accessible to policy makers, media and the public.

Ultrasonography is a non-invasive and safe method for assessing muscle morphology. Among its parameters, echo intensity (EI), derived from grayscale image analysis, has emerged as a promising indicator of muscle quality and intramuscular fat infiltration. This study aims to validate EI as a marker for evaluating muscle quality in a population of Czech children, through integration with gold-standard assessments of muscle strength and body composition. The primary aim of this study is to assess the reliability and construct validity of quadriceps muscle EI using ultrasound as a proxy measure of morphological muscle quality in children aged 10–14 years.

Children aged 10–14 years will undergo ultrasound assessment of the quadriceps femoris (QF). EI will be derived from longitudinal scans of each QF head and the cross-sectional area (CSA_QF) from panoramic mid-thigh images. Muscle function will be assessed as maximal voluntary contraction (MVC) of isometric knee extension with muscle quality expressed as MVC/CSA_QF. A 30 s sit-to-stand test (30STS) will be used as an additional functional measure. EI reliability (intra-rater, inter-rater and test–retest) will be evaluated with intraclass correlation coefficients (ICC), Bland–Altman plots and complementary indices. Exploratory known-groups validity will be tested by comparing EI between weight-status groups. Control variables include dual-energy X-ray absorptiometry (DXA)-derived body composition, skeletal age (as determined by DXA hand scans) and physical activity (assessed using 7-day accelerometry).

This study will include 200 children (100 girls and 100 boys) aged 10–14 years using an a priori power analysis based on the primary objective of assessing construct validity through multiple linear regression, assuming an alpha level of 0.05 and 80% power. Participants will be recruited from paediatric outpatients of the Paediatric Obesity Clinic and individuals reached through a recruitment campaign. Inclusion criteria require general good health, while exclusion criteria include a history or symptoms of cardiovascular, pulmonary, metabolic or neurological disease, as well as the use of over-the-counter or prescribed medications. Informed consent and assent will be obtained from all participants.

Reliability of ultrasound-derived EI will be assessed for intra-rater, inter-rater and test–retest agreement using ICC coefficients, Bland–Altman plots and complementary indices such as SE of measurement, coefficient of variation and minimal detectable change at 95% CI, following Consensus-based Standards for the selection of health Measurement Instruments guidelines. Construct validity will be examined by modelling associations between EI and functional muscle quality (MVC/CSA_QF), with 30STS as an additional functional measure. Known-groups validity will be tested by comparing EI across weight groups, using generalised linear regression models adjusted for skeletal age, body composition and physical activity. All validity analyses will be conducted separately for girls and boys. Ultrasound-derived EI of the QF is expected to show high reliability (ICC≥0.80) and acceptable test–retest reproducibility. Construct validity should be supported by moderate associations with functional muscle quality (MVC/CSA_QF), while known-groups validity is expected to reveal higher EI values in children with obesity and/or insufficient physical activity.

The study will be conducted in accordance with the Declaration of Helsinki and was approved by the Ethics Committee of the Faculty of Physical Education and Sport, Charles University (EK 101/2024). Written parental consent and verbal assent from children will be obtained, with all data handled confidentially and anonymised. Results will be disseminated transparently to participants and their families in line with ethical principles of respect, beneficence and justice.

NCT06792279.

A retrospective cohort study.

A large multispecialty, tertiary referral and teaching hospital in England, UK.

The study included 3175 consecutive adult ICU UPAs from hospital wards over a 6-year period (2014–2019).

Ward-based management of deterioration prior to ICU admission was assessed by the RRT, using a scored checklist—the UPA score. Admissions were compared in two groups according to their exposure to an RRT review in the 72 hours before ICU admission. Associations with in-hospital cardiac arrest within 24 hours before ICU admission and all-cause in-hospital mortality were estimated, using unadjusted and adjusted odds ratios (aORs) with 95%CI.

RRT review occurred in 1413 (44.5%) admissions and was associated with reduced odds of in-hospital cardiac arrest (aOR 0.51; 95% CI 0.36 to 0.78; p

An RRT review in the 72 hours prior to ICU admission was associated with reduced odds of in-hospital cardiac arrest but did not impact in-hospital mortality. Higher UPA scores were associated with increased incidence of both in-hospital cardiac arrest and in-hospital mortality. In addition, this study describes a novel and adaptable RRT scoring tool (the UPA score) for safety monitoring and quality improvement.

Multiple sclerosis (MS) is a chronic neurological condition that affects approximately 150 000 people in the UK and presents a significant healthcare burden, including the high costs of disease-modifying treatments (DMTs). DMTs have substantially reduced the risk of relapse and moderately reduced disability progression. Patients exhibit a wide range of responses to available DMTs. The Predicting Optimal INdividualised Treatment response in MS (POINT-MS) cohort was established to predict the individual treatment response by integrating comprehensive clinical phenotyping with imaging, serum and genetic biomarkers of disease activity and progression. Here, we present the baseline characteristics of the cohort and provide an overview of the study design, laying the groundwork for future analyses.

POINT-MS is a prospective, observational research cohort and biobank of 781 adult participants with a diagnosis of MS who consented to study enrolment on initiation of a DMT at the Queen Square MS Centre (National Hospital of Neurology and Neurosurgery, University College London Hospital NHS Trust, London) between 01/07/2019 and 31/07/2024. All patients were invited for clinical assessments, including the expanded disability status scale (EDSS) score, brief international cognitive assessment for MS and various patient-reported outcome measures (PROMs). They additionally underwent MRI at 3T, optical coherence tomography and blood tests (for genotyping and serum biomarkers quantification), at baseline (i.e., within 3 months from commencing a DMT), and between 6–12 (re-baseline), 18–24, 30–36, 42–48 and 54–60 months after DMT initiation.

748 participants provided baseline data. They were mostly female (68%) and White (75%) participants, with relapsing–remitting MS (94.3%), and with an average age of 40.8 (±10.9) years and a mean disease duration of 7.9 (±7.4) years since symptom onset. Despite low disability (median EDSS 2.0), cognitive impairment was observed in 40% of participants. Most patients (98.4%) had at least one comorbidity. At study entry, 59.2% were treatment naïve, and 83.2% initiated a high-efficacy DMT. Most patients (76.4%) were in either full- or part-time employment. PROMs indicated heterogeneous impairments in physical and mental health, with a greater psychological than physical impact and with low levels of fatigue. When baseline MRI scans were compared with previous scans (available in 668 (89%) patients; mean time since last scan 9±8 months), 26% and 8.5% of patients had at least one new brain or spinal cord lesion at study entry, respectively. Patients showed a median volume of brain lesions of 6.14 cm³, with significant variability among patients (CI 1.1 to 34.1). When brain tissue volumes z-scores were obtained using healthy subjects (N=113, (mean age 42.3 (± 11.8) years, 61.9% female)) from a local MRI database, patients showed a slight reduction in the volumes of the whole grey matter (–0.16 (–0.22 to –0.09)), driven by the deep grey matter (–0.47 (–0.55 to –0.40)), and of the whole white matter (–0.18 (–0.28 to –0.09)), but normal cortical grey matter volumes (0.10 (0.05 to 0.15)). The mean upper cervical spinal cord cross-sectional area (CSA), as measured from volumetric brain scans, was 62.3 (SD 7.5) mm². When CSA z-scores were obtained from the same healthy subjects used for brain measures, patients showed a slight reduction in CSA (–0.15 (–0.24 to –0.10)).

Modelling with both standard statistics and machine learning approaches is currently planned to predict individualised treatment response by integrating all the demographic, socioeconomic, clinical data with imaging, genetic and serum biomarkers. The long-term output of this research is a stratification tool that will guide the selection of DMTs in clinical practice on the basis of the individual prognostic profile. We will complete long-term follow-up data in 4 years (January 2029). The biobank and MRI repository will be used for collaborative research on the mechanisms of disability in MS.

Public involvement in mental health research enhances research quality. The use of citizen science methods in mental health research has been described as a conclusion of a movement towards increased public involvement; however, this field is in its early stages of development. Our objective was to create a theory of change (ToC) for how citizen science can be used to enhance mental health research quality.

Iterative consultation with the stakeholders of an existing citizen mental health science study, that is, change for citizen science to achieve co-production at scale (C-STACS: https://www.researchintorecovery.com/research/c-stacs/)

We co-developed a ToC through an iterative consultation with C-STACS stakeholders who were (a) representatives of mental health community organisations (n=10), individuals with public involvement experience (n=2) and researchers (n=5). In keeping with established ToC practice, entities were identified, including long-term impacts, outcomes needed to create an impact, stakeholder assumptions and indicators for tracking progress.

A desired primary long-term impact of greater co-production of research was identified between researchers and members of the public, which would create a secondary impact of enhancing public capacity to engage in citizen mental health science. We proposed long-term outcomes needed to enable this impact: (1) greater co-production of research objectives and pathways between researcher and the public, (2) greater embedment of citizen mental health science into funder processes (eg, the creation of specific funding calls for citizen mental health science proposals, (3) greater clarity on the boundaries between citizen science and other participatory approaches (eg, so that there is not loss of impact due to conceptual confusion between these, (4) increased knowledge around effective frameworks to enable mass public participation and (5) greater availability of technology platforms, enabling safe and accessible engagement with citizen mental health science projects.

The proposed ToC is grounded in the C-STACS project, but intended to be broadly applicable. It allows the continued formation of a community of practice around citizen mental health science and should be reviewed, as greater knowledge is developed on how citizen mental health science creates change.