{"paper_id":"d6413eb4-278b-4672-8568-a7d372b07bfd","body_text":"Title \nThe waiting room: unmet sexual health service needs among men and gender-diverse individuals having \nsex with men in England, findings from an online, cross-sectional community survey in 2024 \nAuthors:  \nDana Ogaz1,2  \nDolores Mullen1* \nGeorge Baldry1* \nDanielle Jayes1 \nDawn Phillips1 \nCatherine M Lowndes1 \nDavid Reid2,3  \nJordan Charlesworth1 \nErna Buitendam1  \nDavid Phillips4  \nGwenda Hughes5  \nCatherine H Mercer2,3   \nJohn Saunders1,2,3  \nKate Folkard1 \nKaty Sinka1  \nHamish Mohammed1,2,3 \n*joint second authors \nAffiliations: \n1 Blood Safety, Hepatitis, STI & HIV Division, UK Health Security Agency, London, UK 2 The National \nInstitute for Health and Care Research Health Protection Research Unit in Blood Borne and Sexually \nTransmitted Infections at University College London in partnership with the UK Health Security Agency, \nLondon, UK  \n3 Institute for Global Health, University College London, London, UK 4 Croydon Health \nServices NHS Trust, London, UK 5 UK Public Health Rapid Support Team, London School of Hygiene \nand Tropical Medicine, London, UK \n \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \nNOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice.\n\nAbstract \nBackground:  \nSexual health service (SHS) delivery in England has shifted substantially following a rapid expansion of \nonline services during the COVID-19 pandemic. While digital provision may improve reach, there are \nlimited data on the extent of unmet need for in-person SHS in England. We sought to address this among \nmen and gender-diverse individuals who have sex with men in England, a group disproportionately \naffected by sexual health inequalities. \nMethods:  \nWe analysed data from “Reducing inequalities in Sexual Health” (RiiSH) 2024 (Nov/Dec 2024), an \nonline cross-sectional survey of men and gender-diverse individuals who have sex with men residing in \nEngland. We assessed in-person SHS access and among those who tried to access a SHS in the last year - \nunmet need (i.e. participants who tried but were unable to access a SHS in-person) alongside reasons for \ninaccessibility. Using multivariable logistic regression, we examined sociodemographic and behavioural \nassociations with unmet SHS need. \nResults:  \nAmong 2,404 participants living in England (median age 45 years [interquartile range: 36-55], 88% \nWhite, 95% cisgender), 86% reported accessing in-person SHS ever, and 59% in the past year. Of those \nwho tried to access in-person care in the past year, 12% (95% CI: 11%-14%) experienced unmet need, \nespecially Outside London (15% vs. 8% in London). Common barriers included unavailable (50%) or \ninconvenient (41%) appointment times. In adjusted multivariable analysis, unmet need continued to be \nlower among participants living in London (aOR: 0.64 [95% CI: 0.44-0.92]), those financially \ncomfortable (aOR: 0.69 [0.49-0.97]), and those reporting \n≥ 1 marker(s) of sexual risk (e.g. HIV-PrEP use \nin the last year and/or in the last 3-4 months, the report of a bacterial STI diagnosis, engaging in chemsex, \nhaving had \n≥ 10 male physical sex partners; aOR: 0.14 [0.10-0.20]). Unmet need was higher among \nparticipants with limiting long-term physical health conditions (aOR: 1.61 [1.12-2.30]) and those who \nreported ever using online postal self-sampling services for STI testing (OPSS) (aOR: 1.50 [1.07-2.09]). \nConclusions:  \nDespite high SHS engagement, one in ten participants in this national community-based sample reported \nrecent unmet need for in-person SHS. Equity-focused strategies are needed to meet evolving SHS \ndemand. Local service delivery guided by joint strategic needs assessments could help address unmet \nneed for SHS.      \nKeywords:  \nHIV , STI, MSM, gender-diverse, UK, sexual health services \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\nEthical considerations: \nEthical approval of this study was provided by the UKHSA Research and Ethics Governance Group \n(REGG; ref: R&D 524).  \nConsent to participate: \nOnline informed consent was received from all participants and all methods were performed in \naccordance with guidelines and regulations set by the UKHSA REGG. \nDeclaration of conflicting interest: \nAuthors have no conflicting interests to declare. \nFunding statement: \nThe RiiSH 2024 study and authors HM, JS, DR, CHM received partial funding support as part of The \nNational Institute for Health Research Health Protection Research Unit in Blood Borne and Sexually \nTransmitted Infections at University College London in partnership with the UK Health Security Agency \n(https://bbsti.hpru.nihr.ac.uk). The funders had no role in study design, data collection and analysis, \ndecision to publish, or preparation of the manuscript. All other authors received no specific funding for \nthis work. \nData availability: \nThe data that support the findings of this study are not publicly available to protect participant privacy. \nHowever, some aggregate data are available upon reasonable request from the UK Health Security \nAgency (UKHSA). Requests can be directed to DataAccess@ukhsa.gov.uk\n.  \nAcknowledgements:  \nThe authors wish to thank all participants to RiiSH 2024 and Takudzwa Mukiwa (Terrence Higgins Trust) \nfor contributions to survey implementation. Authors acknowledge the members of the National Institute \nfor Health and Care Research Health Protection Research Unit (NIHR HPRU) in Blood Borne and \nSexually Transmitted Infections (BBSTI) Steering Committee: Professor Caroline Sabin (HPRU \nDirector), Dr John Saunders (UKHSA Lead), Professor Catherine H Mercer, Professor Gwenda Hughes, \nDr Hamish Mohammed, Professor Greta Rait, Dr Ruth Simmons, Professor William Rosenberg, Dr \nTamyo Mbisa, Professor Rosalind Raine, Dr Sema Mandal, Dr Rosamund Y u, Dr Samreen Ijaz, Dr \nFabiana Lorencatto, Dr Rachel Hunter, Dr Kirsty Foster and Dr Mamooma Tahir. \n \n \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\nBackground \nIn England, sexual health service delivery is primarily provided through publicly funded services which \nare free, open access (i.e. without referral from primary care), and confidential. Services include testing \nand treatment for sexually transmitted infections (STIs) and provision of STI and HIV prevention \ninterventions (e.g. HIV-PrEP/PEP, doxyPEP, vaccination, condoms). Access is largely available through a \nnetwork of specialist sexual health services (SHS) and increasingly via online platforms offering online \npostal self-sampling kits (OPSS) (i.e. self-collection of samples sent for laboratory testing with results \nsent to users). While some clinics offer walk-in services, many in-person appointments are dependent on \nonline or telephone triage(1), with waiting times varying by local supply and demand.  \nOver the past decade, the sexual health landscape in England has undergone profound transformation(2). \nService provision has been significantly impacted by the COVID-19 pandemic, accelerating already-\nevolving models of service delivery, amidst increasingly constrained public health budgets and clinical \nresources(3, 4). The proportion of OPSS testing provided through SHS has rapidly increased, representing \n13% of all STI testing in 2019 (pre-COVID-19) to 42% in 2024(5). While OPSS has increased the reach \nof SHS for many(6-8), significant barriers remain. These include digital exclusion, low health literacy, \nand difficulties with self-sampling (particularly for blood samples), as well as concerns about \nconfidentiality(9, 10). Service limitations exist on the provision of self-sampling services, such as locally \nimposed restrictions on eligibility and number of test kits available(11, 12). Inherent limitations of online \ninteractions(13, 14) that include reduced ability to identify those with increased risk or complex needs, \ninability to deliver injections (e.g. vaccinations), and obscuring the need for clinicians to provide care for \nacute and complex conditions(13) pose significant challenges to comprehensive sexual health service \nprovision. \nPrevious assessments of unmet need for STI and HIV testing in England have considered the general \npopulation(4), or gay, bisexual, and other men who have sex with men (GBMSM)(15), and have largely \nbeen based on researcher perceived need and defined on behavioural proxies (e.g. based on clinical \nhistory). While important, these assessments do not characterise unmet needs among those attempting to \naccess care or who may already be experiencing SHS access inequalities. Given the changing sexual \nhealth landscape, especially following periods of major disruption and service reconfigurations, there is a \nneed to examine in-person SHS accessibility. We use data collected from a large, online community \nsurvey to characterise SHS access and unmet need among men and gender-diverse individuals having sex \nwith men, which are key groups more likely to experience sexual health inequalities in England(5, 16, \n17). \nMethods   \nData collection and recruitment \nThe ‘Reducing inequalities in Sexual Health’ (RiiSH) 2024 survey is part of a series of yearly, online \ncross-sectional surveys, assessing the sexual health and well-being of a community sample of men and \ngender-diverse individuals who have sex with men in the UK. Recruitment in 2024 took place from 18th \nNovember-11th December. Survey recruitment was conducted through advertisements on social \nnetworking sites (Facebook, Instagram) and geospatial dating platforms (Grindr, Scruff, Jack'd and \nRecon). Survey methods have been previously reported(18, 19). In brief, participants eligible to take part \nincluded self-identifying men (cisgender or transgender), transgender women or gender-diverse  \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\nindividuals who were assigned male at birth, aged ≥ 16 years, resident in the UK and reporting sex with a \nman (cisgender and/or transgender) in the last year. Given differences in the commissioning of sexual \nhealthcare across the four nations of the UK, analyses were restricted to those living in England. \nSHS access \nWe conducted descriptive analyses to examine in-person (i.e. face-to-face) SHS access (‘never’, ‘in the \nlast year’). Among those with an in-person visit in the last year, we examined reasons for last visit (e.g. \nfor STI testing) and why services were chosen (e.g. ‘I felt comfortable here’) (see Appendix I for question \nexcerpts). Results were stratified by region of residence (London, Outside London), where we \nhypothesised greater accessibility in London over other areas. While we posited greater variation in urban \nvs rural areas, these examinations were not possible given lack of granularity in region of residence \nmeasures. We also report the proportion who reported that they had ever used OPSS for STI testing, \ndefined as testing via private or public self-sampling services. \nSHS unmet need \nUnmet need was defined as those unable to access an in-person SHS among those who tried. We report \nthe proportion of participants with unmet need (%, 95% CI) and reasons for SHS inaccessibility by region \nof residence (London, Outside London). \nFactors associated with SHS unmet need  \nWe examined factors associated with unmet need using binary logistic regression among those who tried \nto access a SHS in the last year. We present bivariate and multivariable associations and consider \nevidence of association where p<0.05. All specified covariates were included in multivariable modelling \nbased on a priori consideration (age-group, sexual orientation) and/or associations in previous literature \n(e.g. disability, sexual risk)(20-22). These also included: financial stability (prioritised as a measure of \ndeprivation given strong association with poor sexual health(5) relative to other available measures, \nincluding education); markers of sexual risk (see definition below) as a composite measure given the \nstrong correlation between measures of sexual risk behaviours; as well as region of residence \n(dichotomised as London, Outside London given measure limitations, see above). We considered \ninclusion of self-report of physical conditions or illnesses lasting or expected to last for 12 months or \nmore but prioritised the report of physical limitations due to these conditions (see definition below) as \nthese could influence in-person accessibility. As an indirect measure of digital literacy, and/or of structural \nbarriers to in-person SHS access, we also included the report of ever having used OPSS for STI testing. \nHaving markers of sexual risk was defined as those reporting HIV-PrEP use in the last year and/or in the \nlast 3-4 months: the report of a bacterial STI diagnosis, engaging in chemsex (those that had used crystal \nmeth, mephedrone or GHB/GBL), having had \n≥ 10 male physical sex partners, and meeting partners \nthrough sex-on-premises venues, public sex environments (i.e. cruising environments), or at private sex \nparties (herein collectively called ‘venue risk’).  \nFor those reporting a limitation associated with a long-term physical health condition, we created a binary \nmeasure (i.e. response of ‘Yes – a little’, ‘Yes, a lot’ vs ‘Not at all’ to the question: “Does your condition \nor illness reduce your ability to carry out day-to-day activities). Those not reporting a long-term health \ncondition were classified as having no limitations.   \nSurvey data was collected via the Snap Surveys platform (www.snapsurveys.com). Data management and \nanalyses were conducted using Stata v17.0 or higher (StataCorp, College Station, TX, USA). \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\nEthics statement  \nEthical approval for RiiSH 2023 was granted by the UKHSA Research and Ethics Governance Group \n(REGG; ref: R&D 524). Online consent was collected from participants and there was no incentive \noffered to participate. \nResults  \nOf 2,758 participants recruited to RiiSH 2024, 2,404 were resident in England (87%) and included in \nanalyses (excluded participants included those living in Scotland [n=194], Wales [n=100], and Northern \nIreland [n=60]) (Appendix II).  The median age of included participants was 45 years (interquartile range: \n36-55); most were of White ethnicity (88%), cisgender male (95%), degree-educated (60%) and \nemployed (78%). Nearly one-third resided in London (31%) (Table 1).   \nSHS access \nOf all participants, 86% (2,074/2,404) reported they had ever had an in-person SHS visit (59% \n[1,427/2,404] in the last year) and 40% (944/2,404) reported ever using a self-sampling service for STI \ntesting. Among those who reported never visiting a SHS, most (71% 235/330) also reported they had \nnever used OPSS for STI testing. Of those who had ever visited an in-person SHS, 59% (1,225/2,074) \nreported that they had never used an OPSS (Table 1).  \nReasons for last in-person SHS visit \nAmong those who ever visited a SHS and had done so in the past year (69% 1,427/2,074), wanting an STI \ntest or a general sexual health check-up (62% 889/1,427) and HIV-PrEP access (48% 684/1,427) were the \nmost common reasons for visits (Appendix III).  Only 11% of all participants reported having had \nsymptoms as a reason for their last visit. \nReasons for choosing an in-person SHS \nConsidering reasons for choice of SHS, close proximity to or ease to travel from home (66% 938/1,427) \nwas most commonly reported. Those living in London were less likely to report that their clinic choice \nwas because it was close to home compared to those living Outside London (58% vs 70%) but were more \nlikely to cite proximity to work (24% vs 17%) or because of the service’s reputation (37% vs 16%) as \nreasons. Excellent staff (50% 719/1,427), and services that suited needs (50% 719/1,427) were also \ncommonly reported by all as reasons for choosing the last SHS attended (Appendix IV).  \nSHS unmet need \nAmong those who tried to access a SHS in the last year, 12% (95% CI: 11%-14%, 202/1,629) could not, \nwith this proportion varying by whether the participant lived in London (8% [6%-11%] vs. Outside \nLondon, 15% [12%-17%]; Table 1). \nReasons for in-person SHS inaccessibility among those with unmet need \nAppointment unavailability (50% 102/202) and inconvenient appointment times (41% 82/202) were the \nmost common reasons for inaccessibility (Appendix V). A higher proportion of those reporting unmet \nneed in London reported inconvenient appointment times (46% vs 39%), no appointment availability \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\n(56% vs 49%) and waiting too long for an appointment (33% vs 16%) compared to those living Outside \nLondon.  \nFactors associated with SHS unmet need  \nAll participants who tried to access a SHS in the past year were included in regression models; 4 \nparticipants who did not specify region of residence were excluded from analyses (Table 1). In bivariate \nanalysis, we found a lower likelihood of unmet need amongst older age groups (uOR: 0.55 [0.35-0.86] \naged \n≥ 45 vs 16-29); those living in London (uOR: 0.54 [0.38-0.76]; those reporting financial comfort \n(uOR: 0.59 [0.43-0.80]); and those with at least one marker of sexual risk (uOR: 0.14 [0.10-0.19]). There \nwas a higher likelihood of unmet need amongst those who were bisexual, straight, or described \nthemselves in another way (uOR: 1.82 [1.28-2.59] vs gay/homosexual), had a long-term physical health \ncondition that caused limitations in their everyday life (uOR: 2.01 [1.45-2.77]), and those who had ever \nused a OPSS for STI testing (uOR: 2.01 [1.45-2.77]) (Table 2). \nIn a multivariable logistic regression adjusted for age and sexual orientation (a priori), as well as region \nof residence, self-reported financial comfort, markers of sexual risk, limiting long-term physical health \nconditions and use of OPSS for STI testing, we found no evidence of association by age-group (uOR: \n0.89 [0.53-1.51] aged \n≥ 45 vs 16-29) or sexual orientation (aOR: 1.48 [1.00-2.20]). With adjustment, a \nlower likelihood of unmet need remained amongst London residents (aOR: 0.64 [0.44-0.92]), those \nfinancially comfortable (aOR: 0.69 [0.49-0.97]) and those with markers of sexual risk (aOR: 0.14 [0.10-\n0.20]). Those with a limiting long-term physical health condition (aOR: 1.61 [1.12-2.30]), and those that \nhad ever used an OPSS (aOR: 1.50 [1.07-2.09]) had a higher likelihood of unmet need.  \nDiscussion \nAnalysis of this large, online community survey provides important insights into patterns of SHS use and \nunmet need of men and gender-diverse individuals who have sex with men in England. While most \nparticipants had ever accessed in-person SHS, unmet need was evident among those who had recently \nattempted to access a SHS in-person. Findings emphasise the importance of assessing whether current \nservice models, many of which originate from adaptations made to SHS delivery during the COVID-19 \npandemic, adequately meet contemporary needs. Equitable access to SHS will be critical for successful \nimplementation of preventative interventions such as doxyPEP and 4CMenB vaccination as well as \nongoing HIV combination prevention strategies in England. Ensuring accessibility will be essential to \nrealising the full potential of emerging and existing preventative tools. Continued evaluation of mixed \ndelivery models (in-person, online) will be needed to maximise SHS effectiveness and reach, especially \nwhen addressing symptomatic versus preventative needs. \nIn-person SHS use was high among participants (86% ever), with a visit in the last year reported among \n59% of participants, highlighting the continued demand for in-person care even amid the growing \navailability of remote SHS delivery such as self-sampling. Having symptoms did not appear to be a major \ndriver of attending SHS in this sample; however, HIV-PrEP access (48%) and STI testing (62%) were \nboth common reasons for seeking an in-person visit. Both reasons may reflect the high uptake of HIV-\nPrEP among GBMSM in England, and adherence to national recommendations for quarterly STI and HIV \ntesting for individuals having condomless sex with new partners(23-25), reinforcing the integral role of \nSHS for delivering STI preventative care. Only 40% had ever used an OPSS for STI testing, and many \nwho had attended in-person SHS had never used an OPSS, suggesting that online options may not yet be \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\nfully accessible or substitutive for all. Understanding the reasons for preferring in-person versus OPSS, \nincluding trust, convenience, or additional support, requires further exploration.  \nThough most RiiSH participants accessed an in-person SHS, 12% of those who tried to access in-person \ncare in the past year reported unmet need, with this proportion significantly higher for those groups \nknown to be more likely to experience health inequalities. For example, we found higher unmet need \nreported by a higher proportion of participants identifying as bisexual or heterosexual, indicating ongoing \nbarriers in service design or engagement strategies, particularly in services targeted to self-identifying gay \nand bisexual men. These findings highlight the need for more inclusive programmes of targeted \ninterventions and a stronger equity lens in SHS provision and commissioning (26, 27). Financial comfort, \nliving in London, and having at least one marker of sexual risk were independently associated with lower \nlikelihood of unmet SHS need, while unmet need was higher among those with a long-term limiting \nhealth condition and those who had previously used OPSS. These findings underscore the complexity of \naccess, which is not just about service availability but, at an individual level, must also consider capacity \nand preference to use those services. Our findings echo those from quasi-representative surveys of the \ngeneral population, which reported a higher likelihood of unmet need among individuals with a limiting \nlong-term condition, a stark reflection of persistent barriers to SHS faced by people living with \ndisabilities(21, 28).  \nUnmet need also varied substantially by whether participants lived in or Outside London, suggesting that \nin-person SHS may not equally serve or be equally available to people living in different parts of \nEngland. This may also reflect greater SHS availability in London  relative to other  locations in England, \nwhere, by region, London has one of the highest number of SHSs in England (42/247)(29). Appointment \nunavailability and inconvenient appointment times were commonly-reported barriers to in-person SHS \naccess, but were reported more frequently by London residents, potentially reflecting system pressure in \nhigh-demand services(2, 30). A mixed methods assessment of the use of OPSS services in the UK found \nthat in-person SHS case-mix complexity increased following the introduction of OPSS(31). While the use \nof online services and lower levels of unmet need among those with markers of sexual risk suggests \nredirections of clinical complexity that prioritise those with the greatest clinical need, the impacts of this \ndisplacement among other potential service users are largely unexplored. Even less is known about the \nrole of SHS as a gateway to broader healthcare in England, including mental health services, vaccination, \nand substance misuse support(32, 33). The importance of these touchpoints should be a key consideration \nin digital health planning, especially as digital services could expand(34).  \nOverall, our findings suggest the need for the evaluation of SHS service models, which will require a \ncalibrated balance between in-person and online services in order to meet the needs of men and gender-\ndiverse individuals who have sex with men more broadly. While digital services may increase reach and \nservice capacity(35, 36), they should not replace in-person care where it is essential (e.g. vaccination) or \ncould be the gateway to wider healthcare provision for vulnerable or marginalised groups who could \nbenefit from further or integrated services(37). Barriers to in-person access, where appropriate, must be \nminimised. Locally informed, equity-focused strategies are essential for addressing these gaps. We posit \nthat joint strategic needs assessments(38) conducted at local level and used to inform SHS commissioning \ncould act as key levers for targeted interventions that could minimise unmet need. These assessments \nmust consider local demand, structural inequalities, and service capacity (39) to reduce unmet need \namong those most at risk of being underserved, including sexual minorities, people with disabilities, and \nthose living in areas with fewer SHS, as identified in this analysis.  \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\nStrengths and limitations   \nA strength of this study is that it reports data from a large, community-based sample of people living \nacross England. However, participants likely overrepresent individuals already engaged in SHS, and may \nnot reflect experiences of under-engaged groups. Self-reported data may also be subject to recall or social \ndesirability bias. While we did capture area of participant residence, this may not be geographically \nrepresentative. This study did not have the statistical power to consider regional differences, or rural and \nurban settings, where STI and HIV epidemiology and SHS accessibility varies(5). Alongside, we have no \ninformation on distance to in-person SHS, or on the role of SHS loyalty to specific services where \nreputation may affect service availability which was more common as a reason for choosing a service \namong London-based participants. It is unclear whether OPSS were used following in-person \ninaccessibility. We found a higher likelihood of unmet need among those who had ever used an OPSS. \nHowever, due to the cross-sectional nature of this study, it is unclear whether this reflects barriers to in-\nperson services or is an indication of routine STI testing practices among participants, such as regular STI \ntesting (including through OPSS) as part of HIV-PrEP care pathways(23). \nWe defined unmet need largely as an expressed need(40) among those who self-reported that they had \ntried and been unable to access a SHS in the last year. However, expressed need may not equate to actual \nor objective need.  Our measure could have variable effects. Unmet need could be underestimated as it \ndoes not capture individuals affected by broader individual-level (e.g., lack of knowledge, low health \nliteracy) and structural barriers (e.g. regional SHS and OPSS availability, stigma) that may prevent SHS \nengagement altogether. At the same time, the use of expressed need could have overestimated unmet \nneed, as participants facing SHS inaccessibility would be more likely to recall and report difficulties.  \nService access questions (e.g. reasons for visit, why services were chosen) were based on formative work \nand cognitive testing(18) that preceded the COVID-19 pandemic, where online services were less \ncommon; however major service provision changes were in place at that time (e.g. HIV-PrEP \naccessibility, quarterly STI and HIV testing recommendations). Notably, even though this sample likely \nrepresents a population highly engaged with SHS, unmet need was still present. This may imply that even \ngreater access challenges could exist for groups with a lower perceived risk of STI/HIV acquisition (e.g. \nheterosexual women, older age groups) or those who may have other unique barriers to using online \nservices. \nConclusion \nWhile engagement with SHS was high, unmet need was evident among this highly health literate sample. \nThese findings highlight the challenges of maintaining quality in-person SHS while scaling accessible \ndigital options. Addressing these needs will require equity-focused, locally curated strategies and services. \n \n \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\nReferences \n1. British Association for Sexual Health  and HIV (BASHH). Standards for the Management \nof STIs 2019 [cited 2025 01 August]. Available from: \nhttps://www.bashh.org/resources/81/standards_for_the_management_of_stis/. \n2. Local Government Association. Breaking point: Securing the future of sexual health \nservices. 2022 [Available from: https://www.local.gov.uk/publications/breaking-point-securing-\nfuture-sexual-health-services. \n3. Dema E, Sonnenberg P, Gibbs J, Conolly A, Willis M, Riddell J, et al. How did the \nCOVID-19 pandemic affect access to condoms, chlamydia and HIV testing, and cervical cancer \nscreening at a population level in Britain? (Natsal-COVID). Sex Transm Infect. 2023;99(4):261-\n7. \n4. Dema E, Gibbs J, Clifton S, Copas AJ, Tanton C, Riddell J, et al. Initial impacts of the \nCOVID-19 pandemic on sexual and reproductive health service use and unmet need in Britain: \nfindings from a quasi-representative survey (Natsal-COVID). 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(which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\nTable 1: Sociodemographic, clinical and behavioural characteristics of 1) all participants and 2) \nthose who tried to access a sexual health service in the last year \n  All participants Those who tried to access a SHS in the last \nyear¶¶ \nTotal  2,404 (100.0%) 1,629 (100.0%) \nSociodemographic characteristics   \nAge at survey completion (years) 45 (36-55) 45 (36-54) \nMean age at survey completion (years) 45.4 (13.2) 45.2 (12.7) \nAge-group (3 categories)   \n  16-29 290 (12.1%) 168 (10.3%) \n  30-44 875 (36.4%) 640 (39.3%) \n  45 and over 1,239 (51.5%) 821 (50.4%) \nEthnic group (all categories)   \n  White 2,104 (87.5%) 1,398 (85.8%) \n  Black 55 (2.3%) 44 (2.7%) \n  Asian 134 (5.6%) 99 (6.1%) \n  Mixed or other 111 (4.6%) 87 (5.4%) \nEthnic group (2 categories)   \n  All other ethnic groups 300 (12.5%) 231 (14.2%) \n  White 2,104 (87.5%) 1,398 (85.8%) \nGender identity and sex at birth   \n  All other gender identity groups 110 (4.6%) 76 (4.7%) \n  Cisgender male 2,294 (95.4%) 1,553 (95.3%) \nSexual orientation   \n  Gay/homosexual 1,940 (80.7%) 1,366 (83.9%) \n  Bisexual, straight/heterosexual, or another \nway‡ \n464 (19.3%) 263 (16.1%) \nRegion of residence (England)   \n  London 748 (31.1%) 570 (35.0%) \n  South East 323 (13.4%) 205 (12.6%) \n  South West 194 (8.1%) 111 (6.8%) \n  West Midlands 162 (6.7%) 100 (6.1%) \n  North West 316 (13.1%) 218 (13.4%) \n  North East 89 (3.7%) 61 (3.7%) \n  Yorkshire and Humber 189 (7.9%) 122 (7.5%) \n  East Midlands 168 (7.0%) 97 (6.0%) \n  East of England 206 (8.6%) 141 (8.7%) \n  England - unknown 9 (0.4%) 4 (0.2%) \nUK born   \n  No 548 (22.8%) 403 (24.7%) \n  Yes 1,856 (77.2%) 1,226 (75.3%) \nEducational qualifications   \n  Below degree-level 968 (40.3%) 611 (37.5%) \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\n  Degree-level or higher 1,436 (59.7%) 1,018 (62.5%) \nEmployment   \n  Not employed 539 (22.4%) 349 (21.4%) \n  Current employment (full/part-time, self-\nemployed) \n1,865 (77.6%) 1,280 (78.6%) \nComfortable financial situation   \n No 1,306 (54.3%) 883 (54.2%) \n  Yes (top two quartiles)§ 1,098 (45.7%) 746 (45.8%) \nClinical and behavioural characteristics   \nHIV status   \n  Negative/unknown 2,140 (89.0%) 1,408 (86.4%) \n  PLWHIV (tested positive) 264 (11.0%) 221 (13.6%) \nHIV-PrEP use since Dec 2023 (in last year)   \n  No (includes PLWHIV and those never \nreported use) \n1286 (53.5%) 596 (36.6%) \n  Yes 1,118 (46.5%) 1,033 (63.4%) \nEver used STI antibiotic post-exposure \nprophylaxis for the prevention of STIs \n  \n  No 2,073 (86.2%) 1,343 (82.4%) \n  Yes 331 (13.8%) 286 (17.6%) \nEver reported recreational drug use associated \nwith chemsex  \n  \n  No 2,044 (85.0%) 1,335 (82.0%) \n  Yes 360 (15.0%) 294 (18.0%) \nNo. of male physical sex partners since Aug \n2024 (in last 3-4 months) \n  \n  No sex/only virtual sex 215 (8.9%) 104 (6.4%) \n  1 274 (11.4%) 121 (7.4%) \n  2-4 715 (29.7%) 431 (26.5%) \n  5-9 519 (21.6%) 394 (24.2%) \n  10 or more 681 (28.3%) 579 (35.5%) \nWhether any male physical sex partners were \nnew since Aug 2024 (in last 3-4 months) \n  \n  No new partners 539 (22.4%) 258 (15.8%) \n  1 or more new partners 1,865 (77.6%) 1,371 (84.2%) \nWhether had vaginal/anal sex with a woman \nsince Aug 2024 (in last 3-4 months) \n  \n  No 2,266 (94.3%) 1,561 (95.8%) \n  Yes 138 (5.7%) 68 (4.2%) \nVenue risk¶   \n  No 1,595 (66.3%) 968 (59.4%) \n  Yes 809 (33.7%) 661 (40.6%) \nBacterial STI diagnosis since Aug 2024 (in \nlast 3-4 months) \n  \n  No 2,160 (89.9%) 1,393 (85.5%) \n  Yes 244 (10.1%) 236 (14.5%) \nLimiting long-term physical health condition   \n  No 1,904 (79.2%) 1,290 (79.2%) \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\n  Yes 500 (20.8%) 339 (20.8%) \nLimiting long-term mental health condition   \n  No 1,816 (75.5%) 1,214 (74.5%) \n  Yes 588 (24.5%) 415 (25.5%) \nMarkers of sexual risk (composite) ‡‡   \n  No 836 (34.8%) 319 (19.6%) \n  Yes 1,568 (65.2%) 1,310 (80.4%) \nEver used a private or public OPSS§§   \n  No 1,460 (60.7%) 956 (58.7%) \n  Yes 944 (39.3%) 673 (41.3%) \nEver visited an in-person SHS   \n  No 330 (13.7%) 46 (2.8%) \n  Yes 2,074 (86.3%) 1,583 (97.2%) \nTried to access in-person SHS in last year   \n  No 775 (32.2%)  … \n  Yes, tried but unsuccessful 202 (8.4%)  202 (12.4%) \n  Yes, visited in-person SHS 1,427 (59.4%) 1,427 (87.6%) \n‡Includes those identifying as bisexual, straight, or another way. §Top two quartiles (\"I am comfortable\"/\"I am very comfortabl e\" from the \nquestion, \"How would you best describe your current financial situation\". ¶ Met male partners through sex-on-premises venues, public sex \nenvironments (i.e. cruising environments), or at private sex parties. ‡‡ Includes reporting of: HIV-PrEP use in the last year ( i.e. since Dec 2023), \nand/or in the last 3-4 months (i.e. since Aug 2024), the report of a bacterial STI diagnosis, engaging in chemsex, having had ≥ 10 male physical \nsex partners, and meeting partners through sex-on-premises venues, public sex environments (i.e. cruising environments), or at private sex \nparties. §§ Online and postal self-sampling services for STI testing. ¶¶ Includes 4 participants with missing data on region of  England residence \nand were not included in modelling (see Table 2). PLWHIV=people living with HIV . HIV-PrEP=HIV pre-exposure prophylaxis. STI=sexually \ntransmitted infection. SHS=sexual health service. OPSS=Online and postal self-sampling for STI testing. RiiSH='Reducing inequal ities in Sexual \nHealth'. \n  \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint \n\nTable 2. Sociodemographic, clinical and behavioural characteristics associated with unmet need \namong those trying to access a sexual health service in the last year \n uOR (95% CI) aOR (95% CI) ‡‡ p-value \nSociodemographic characteristics    \nAge-group (3 categories)      \n16-29 1.00 (base) 1.00 (base) 0.493 \n30-44 0.69 (0.44-1.10) 1.11 (0.66-1.85)  \n45 and over 0.55 (0.35-0.86) 0.89 (0.53-1.51)  \nSexual orientation      \nGay/homosexual 1.00 (base) 1.00 (base) 0.057 \nBisexual, straight/heterosexual, or another way‡ 1.82 (1.28-2.59) 1.48 (1.00-2.20)  \nLondon resident      \nNo 1.00 (base) 1.00 (base) 0.014 \nYes 0.54 (0.38-0.76|) 0.64 (0.44-0.92)  \nComfortable financial situation      \n No 1.00 (base) 1.00 (base) 0.031 \n  Yes (top two quartiles)§ 0.59 (0.43-0.80) 0.69 (0.49-0.97)  \nClinical and behavioural characteristics      \nMarkers of sexual risk (composite) ¶      \nNo 1.00 (base) 1.00 (base) <0.001 \nYes 0.14 (0.10-0.19) 0.14 (0.10-0.20)  \nLimiting long-term physical health condition      \nNo 1.00 (base) 1.00 (base) 0.011 \nYes 2.01 (1.45-2.77) 1.61 (1.12-2.30)  \nEver used a private or public OPSS§     \nNo 1.00 (base) 1.00 (base) 0.019 \nYes 1.06 (0.79-1.43) 1.50 (1.07-2.09)  \n‡Includes those identifying as bisexual, straight, or another way. §Top two quartiles (\"I am comfortable\"/\"I am very comfortabl e\" from the \nquestion, \"How would you best describe your current financial situation\". ¶ Includes reporting of: HIV-PrEP use in the last yea r (i.e. since Dec \n2023), and/or in the last 3-4 months (i.e. since Aug 2024), the report of a bacterial STI diagnosis, engaging in chemsex, having had ≥ 10 male \nphysical sex partners, and meeting partners through sex-on-premises venues, public sex environments (i.e. cruising environments ), or at private \nsex parties. § Online and postal self-sampling services for STI testing. ‡‡Includes 1625 observations; excludes 4 participants that did not specify \nEngland region of residence. HIV-PrEP=HIV pre-exposure prophylaxis. STI=sexually transmitted infection. SHS=sexual health servi ce. \nOPSS=online and postal self-sampling for STI testing. RiiSH='Reducing inequalities in Sexual Health'. uOR=unadjusted odds ratio . \naOR=adjusted odds ratio. \n . CC-BY 4.0 International licenseIt is made available under a \n is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review)\nThe copyright holder for this preprint this version posted October 8, 2025. ; https://doi.org/10.1101/2025.10.01.25337058doi: medRxiv preprint","source_license":"CC-BY-4.0","license_restricted":false}