Conducting an RCT of a sexual health intervention during the COVID-19 pandemic: Lessons learned

Preprint: Gender-Neutral Human Papillomavirus (HPV) Vaccination in Men: A Mixed-Methods Data Synthesis Leveraging Empirical Prevalence and Cost-Effectiveness Evidence
Wenzhen Wei, Gary M. Clifford, Jason J. Ong, Sten H. Vermund, Xianglin Guo, Tom Nadarzynski, anna beltrame, Anna Giuliano, Pengming Sun, Qing Cong, Shiyuan Hong, Suzanne Marie Garland and Huachun Zou 2026. Preprint: Gender-Neutral Human Papillomavirus (HPV) Vaccination in Men: A Mixed-Methods Data Synthesis Leveraging Empirical Prevalence and Cost-Effectiveness Evidence. SSRN. https://doi.org/10.2139/ssrn.7517043

The Role of Artificial Intelligence in the Prevention of Intimate Partner Violence and Sexual Violence: A Scoping Review of the Literature
Marcantonio, T.L., Vowels, L.M., LeRoux, S, Bravo, M., Thrash, A., Mueller, A., Niolet, A., Hall, M., Döring, N. and Nadarzynski, T. 2026. The Role of Artificial Intelligence in the Prevention of Intimate Partner Violence and Sexual Violence: A Scoping Review of the Literature. Journal of Sex Research. Advanced online publication. https://doi.org/10.1080/00224499.2026.2686406

Exploring acceptability of AI-enabled voice assistants and digital AI humans in healthcare: a cross-sectional survey
Miles, O., Pinckard, S., Gungor, M., Ridge, Damien T. and Nadarzynski, T. 2025. Exploring acceptability of AI-enabled voice assistants and digital AI humans in healthcare: a cross-sectional survey. AI & Society. 40, pp. 6783-6797. https://doi.org/10.1007/s00146-025-02332-8

Impact of Online Interactive Decision Tools on Women’s Decision-Making Regarding Breast Cancer Screening: Systematic Review and Meta-Analysis
Villain, P., Downham, L., Le Bonniec, A., Bauquier, C., Mandrik, O., Nadarzynski, T., Donelle, L., Murillo, R., Tolma, E., Johnson, S., Soler-Michel, P. and Smith, R. 2025. Impact of Online Interactive Decision Tools on Women’s Decision-Making Regarding Breast Cancer Screening: Systematic Review and Meta-Analysis. Journal of Medical Internet Research. 27 e65974. https://doi.org/10.2196/65974

The complex social, cultural and psychological drivers of the ‘chemsex’ experiences of men who have sex with men: a systematic review and conceptual thematic synthesis of qualitative studies
Mundy, E., Carter, A., Nadarzynski, T., Whiteley, C., de Visse, R. and Llewellyn, C. 2025. The complex social, cultural and psychological drivers of the ‘chemsex’ experiences of men who have sex with men: a systematic review and conceptual thematic synthesis of qualitative studies. Frontiers in Public Health. 13 1422775. https://doi.org/10.3389/fpubh.2025.1422775

Chatbot -assisted self-assessment (CASA): Co-designing an AI -powered behaviour change intervention for ethnic minorities
Tom Nadarzynski, Knights, N., Deborah Husbands, Cynthia Graham, Carrie D. Llewellyn, Tom Buchanan, Ian Montgomery, Alejandra Soruco Rodriguez, Chimeremumma Ogueri, Nidhi Singh, Evan Rouse, Olabisi Oyebode, Ankit Das, Grace Paydon, Gurpreet Lall, Anathoth Bulukungu, Nur Yanyali, Alexandra Stefan and Damien Ridge 2025. Chatbot -assisted self-assessment (CASA): Co-designing an AI -powered behaviour change intervention for ethnic minorities. PLoS Digital Health. 4 (2), p. e0000724. https://doi.org/10.1371/journal.pdig.0000724

Impact of Online Interactive Decision Tools on Women’s Decision-Making Regarding Breast Cancer Screening: Systematic Review and Meta-Analysis
Patricia Villain, Laura Downham, Alice Le Bonniec, Charlotte Bauquier, Olena Mandrik, Tom Nadarzynski, Lorie Donelle, Raúl Murillo, Eleni L Tolma, Sonali Johnson, Patricia Soler-Michel and Robert Smith 2025. Impact of Online Interactive Decision Tools on Women’s Decision-Making Regarding Breast Cancer Screening: Systematic Review and Meta-Analysis. Journal of Medical Internet Research. 27 e65974. https://doi.org/10.2196/65974

Chatbot-Assisted Self-Assessment (CASA): Co-designing an AI-powered behaviour change intervention for ethnic minorities (Database)
Nadarzynski, T. 2024. Chatbot-Assisted Self-Assessment (CASA): Co-designing an AI-powered behaviour change intervention for ethnic minorities (Database). University of Westminster. https://doi.org/10.34737/ww606

Preprint: Impact of Online Interactive Decision Tools on Women’s Decision-Making Regarding Breast Cancer Screening: Systematic Review and Meta-Analysis (Preprint)
Patricia Villain, Laura Downham, Alice Le Bonniec, Charlotte Bauquier, Olena Mandrik, Tom Nadarzynski, Lorie Donelle, Raúl Murillo, Eleni L Tolma, Sonali Johnson, Patricia Soler-Michel and Robert Smith 2024. Preprint: Impact of Online Interactive Decision Tools on Women’s Decision-Making Regarding Breast Cancer Screening: Systematic Review and Meta-Analysis (Preprint). JMIR Publications. https://doi.org/10.2196/preprints.65974

Evaluating the Home-based Intervention Strategy (HIS-UK) to reduce new chlamydia infection among young men aged 16-25 years by promoting correct and consistent condom use: Findings from a randomised controlled trial
Stone, N., Graham, C., Bremner, S., McGrath, N., Bedford, R., Brown, K. E., Newby, K., Clarke, A., Jackson, L., Morrison, L., Nadarzynski, T. and To, Y. 2024. Evaluating the Home-based Intervention Strategy (HIS-UK) to reduce new chlamydia infection among young men aged 16-25 years by promoting correct and consistent condom use: Findings from a randomised controlled trial. BMC Health Services Research. 24 (1) 1607.

The impact of chatbot-assisted self-assessment (CASA) on intentions for sexual health screening in people from minoritised ethnic groups at risk of sexually transmitted infections
Nadarzynski, T., Knights, N., Husbands, D., Graham, C. A., Llewellyn, C. D., Buchanan, T., Montgomery, I., Khlafa, N., Tichackova, J., Odeyemi, R., Johnson, S., Jesuthas, N., Tahia, S. and Ridge, Damien T. 2024. The impact of chatbot-assisted self-assessment (CASA) on intentions for sexual health screening in people from minoritised ethnic groups at risk of sexually transmitted infections . Sexual Health. 21 SH24058. https://doi.org/10.1071/sh24058

An Exploratory Study Investigating the Correlates of Sexual Health Anxiety and Preferences for Digital Services Amongst Internet Users
Gervan Arneaud, Tom Buchanan, Chantal Gautier and Tom Nadarzynski 2024. An Exploratory Study Investigating the Correlates of Sexual Health Anxiety and Preferences for Digital Services Amongst Internet Users. Journal of Psychosexual Health. 5 (4), pp. 228-239. https://doi.org/10.1177/26318318231221923

“But can chatbots understand sex?” Attitudes towards artificial intelligence chatbots amongst sexual and reproductive health professionals: An exploratory mixed-methods study
Tom Nadarzynski, Alexandria Lunt, Nicky Knights, Jake Bayley and Carrie Llewellyn 2023. “But can chatbots understand sex?” Attitudes towards artificial intelligence chatbots amongst sexual and reproductive health professionals: An exploratory mixed-methods study. International Journal of STD & AIDS. 34 (11), pp. 809-816. https://doi.org/10.1177/09564624231180777

Reasons for incomplete STI vaccination among men who have sex with men in an English sexual health service
Heather L Armstrong, Clare Scholfield, Ynez Symonds, Tom Nadarzynski and Cynthia A Graham 2023. Reasons for incomplete STI vaccination among men who have sex with men in an English sexual health service. International Journal of STD & AIDS. 34 (8), pp. 532-540. https://doi.org/10.1177/09564624231165078

Sexual health in the UK: the experience of racially minoritised communities and the need for stakeholder input
Dwayne-Wilson Hunt, Rageshri Dhairyawan, Annabel Sowemimo, Tom Nadarzynski, Uzochi Nwaosu, Shardia Briscoe-Palmer, Joseph Heskin, Frances Lander and Taslima Rashid 2023. Sexual health in the UK: the experience of racially minoritised communities and the need for stakeholder input. Sexually Transmitted Infections. 99, pp. 211-212. https://doi.org/10.1136/sextrans-2022-055605

The Impact of First UK-Wide Lockdown (March–June 2020) on Sexual Behaviors in Men and Gender Diverse People Who Have Sex with Men During the COVID-19 Pandemic: A Cross-Sectional Survey
Tom Nadarzynski, Will Nutland, Phil Samba, Jake Bayley and T. Charles Witzel 2023. The Impact of First UK-Wide Lockdown (March–June 2020) on Sexual Behaviors in Men and Gender Diverse People Who Have Sex with Men During the COVID-19 Pandemic: A Cross-Sectional Survey. Archives of Sexual Behavior. 52, pp. 617-627. https://doi.org/10.1007/s10508-022-02458-6

Reducing New Chlamydia Infection Among Young Men by Promoting Correct and Consistent Condom Use: Protocol for a Randomized Controlled Trial
Nicole Stone, Rowena Bedford, Katie Newby, Katherine Brown, Louise Jackson, Stephen Bremner, Leanne Morrison, Nuala McGrath, Tom Nadarzynski, Jake Bayley, Nicky Perry and Cynthia Graham 2022. Reducing New Chlamydia Infection Among Young Men by Promoting Correct and Consistent Condom Use: Protocol for a Randomized Controlled Trial. JMIR Research Protocols. 11 (8) e35729. https://doi.org/10.2196/35729

Mental Well-Being and Sexual Intimacy among Men and Gender Diverse People Who Have Sex with Men during the First UK COVID-19 Lockdown: A Mixed-Methods Study.
Edelman, N.L., Witzel, T.C., Samba, P., Nutland, W. and Nadarzynski, T. 2022. Mental Well-Being and Sexual Intimacy among Men and Gender Diverse People Who Have Sex with Men during the First UK COVID-19 Lockdown: A Mixed-Methods Study. International Journal of Environmental Research and Public Health. 19 (12) 6985. https://doi.org/10.3390/ijerph19126985

Health chatbots acceptability moderated by perceived stigma and severity: A cross-sectional survey
Miles, O., West, R. and Nadarzynski, T. 2021. Health chatbots acceptability moderated by perceived stigma and severity: A cross-sectional survey. Digital Health. 7. https://doi.org/10.1177/20552076211063012

Feasibility study of the Home-based Exercises for Responsible Sex (HERS) intervention to promote correct and consistent condom use among young women.
Knights, Nicola, Stone, Nicole, Nadarzynski, Tom, Brown, Katherine, Newby, Katie and Graham, C. 2021. Feasibility study of the Home-based Exercises for Responsible Sex (HERS) intervention to promote correct and consistent condom use among young women. Pilot and Feasibility Studies. 7 (1), p. 145. https://doi.org/10.1186/s40814-021-00885-1

Barriers and facilitators to engagement with artificial intelligence (AI)-based chatbots for sexual and reproductive health advice: a qualitative analysis.
Nadarzynski, Tom, Puentes, Vannesa, Pawlak, Izabela, Mendes, Tania, Montgomery, Ian, Bayley, Jake and Ridge, Damien 2021. Barriers and facilitators to engagement with artificial intelligence (AI)-based chatbots for sexual and reproductive health advice: a qualitative analysis. Sexual Health. 18 (5), pp. 385-393. https://doi.org/10.1071/SH21123

Using protection motivation theory to explain the intention to initiate human papillomavirus vaccination among men who have sex with men in China
Huang, Ruonan, Wang, Zhenyu, Yuan, Tanwei, Nadarzynski, Tom, Qian, Han-Zhu, Li, Peiyang, Meng, Xiaojun, Wang, Guanghui, Zhou, Yepeng, Luo, Danyang, Wang, Ying, Cai, Yong and Zou, Huachun 2021. Using protection motivation theory to explain the intention to initiate human papillomavirus vaccination among men who have sex with men in China. Tumour Virus Research. 12 200222. https://doi.org/10.1016/j.tvr.2021.200222

Sexual healthcare professionals’ views on the rapid provision of remote services at the beginning of COVID-19 pandemic: A mixed-methods study
Lunt, Alexandria, Llewellyn, C., Bayley, Jake and Nadarzynski, T. 2021. Sexual healthcare professionals’ views on the rapid provision of remote services at the beginning of COVID-19 pandemic: A mixed-methods study. International Journal of STD & AIDS. 32 (12), pp. 1138-1148. https://doi.org/10.1177/09564624211023018

Vaccine acceptability, uptake and completion amongst men who have sex with men: A systematic review, meta-analysis and theoretical framework
Nadarzynski, T., Frost, M., Miller, D., Wheldon, Christopher W., Wiernik, Brenton M., Zou, Huachun, Richardson, Daniel, Marlow, L., Smith, Helen, Jones, C. and Llewellyn, C. 2021. Vaccine acceptability, uptake and completion amongst men who have sex with men: A systematic review, meta-analysis and theoretical framework. Vaccine. 39 (27), pp. 3565-3581. https://doi.org/10.1016/j.vaccine.2021.05.013

Does online sexually transmitted infection screening compromise care? A service evaluation comparing the management of chlamydial infection diagnosed online and in clinic
Gasmelsid, N., Moran, B., Nadarzynski, T., Patel, R. and Foley, E. 2021. Does online sexually transmitted infection screening compromise care? A service evaluation comparing the management of chlamydial infection diagnosed online and in clinic. International Journal of STD & AIDS. 32 (6), pp. 528-532. https://doi.org/10.1177/0956462420980929

Understanding the diverse sexual repertoires of men who have sex with men, trans and gender-diverse groups is important for sexually transmitted infection prevention
Richardson, D., Nambiar, K. and Nadarzynski, T. 2021. Understanding the diverse sexual repertoires of men who have sex with men, trans and gender-diverse groups is important for sexually transmitted infection prevention. BMJ Sexual & Reproductive Health. 47 (3). https://doi.org/10.1136/bmjsrh-2020-200804

Acceptability of remote prescribing and postal delivery services for contraceptive pills and treatment of uncomplicated Chlamydia trachomatis
Nadarzynski, T., Symonds, Y., Carroll, R., Gibbs, J., Kidsley, S. and Graham, C. A. 2020. Acceptability of remote prescribing and postal delivery services for contraceptive pills and treatment of uncomplicated Chlamydia trachomatis. BMJ Sexual and Reproductive Health. 47, pp. 185-192. https://doi.org/10.1136/bmjsrh-2020-200687

Perceived barriers and facilitators to female condoms among UK based healthcare professionals
Burton, Jack, Bedford, Rowena, Graham, C. and Nadarzynski, T. 2020. Perceived barriers and facilitators to female condoms among UK based healthcare professionals. The European Journal of Contraception & Reproductive Health Care. 25 (4), pp. 299-304. https://doi.org/10.1080/13625187.2020.1777966

Acceptability of artificial intelligence (AI)-enabled chatbots, video consultations and live webchats as online platforms for sexual health advice
Nadarzynski, T., Bayley, J., Llewellyn, C., Kidsley, S. and Graham, C.A. 2020. Acceptability of artificial intelligence (AI)-enabled chatbots, video consultations and live webchats as online platforms for sexual health advice. BMJ Sexual and Reproductive Health. 46, pp. 210-217. https://doi.org/10.1136/bmjsrh-2018-200271

Attitudes of pregnant women and healthcare professionals towards clinical trials and routine implementation of antenatal vaccination against respiratory syncytial virus: a multi-centre questionnaire study
Wilcox, Christopher R., Calvert, Anna, Metz, Jane, Kilich, Eliz, MacLeod, Rachael, Beadon, Kirsten, Heath, Paul T, Khalil, Asma, Finn, Adam, Snape, Matthew, Vandrevala, Tushna, Nadarzynski, T., Coleman, Matthew and Jones, Christine 2019. Attitudes of pregnant women and healthcare professionals towards clinical trials and routine implementation of antenatal vaccination against respiratory syncytial virus: a multi-centre questionnaire study. The Pediatric Infectious Disease Journal. 38 (9), pp. 944-951. https://doi.org/10.1097/INF.0000000000002384

Acceptability of artificial intelligence (AI)-led chatbot services in healthcare: A mixed-methods study
Nadarzynski, T., Miles, O., Cowie, A. and Ridge, Damien T. 2019. Acceptability of artificial intelligence (AI)-led chatbot services in healthcare: A mixed-methods study. Digital Health. 5, pp. 1-12. https://doi.org/10.1177/2055207619871808

Digital Health Psychology
Yardley, L., Bradbury, K., Nadarzynski, T. and Hunter, C. 2019. Digital Health Psychology. in: Revenson, T.A. and Gerung, R.A.R. (ed.) Handbook of Health Psychology New York Routledge. pp. 519-525

Preferences for HIV testing services among men who have sex with men in the UK: A discrete choice experiment
Miners, A., Nadarzynski, T., Witzel, C, Phillips, A.N., Cambiano, V., Rodger, A.J. and Llewellyn, C.D. 2019. Preferences for HIV testing services among men who have sex with men in the UK: A discrete choice experiment. PLoS Medicine. 16 (4) e1002779. https://doi.org/10.1371/journal.pmed.1002779

Mixed-methods study in England and Northern Ireland to understand young men who have sex with men’s knowledge and attitudes towards human papillomavirus vaccination
Kesten, J.M., Flannagan, C., Ruane-McAteer, E., Merriel, S.W.D., Nadarzynski, T., Shapiro, G.K., Rosberger, Z. and Prue, G. 2019. Mixed-methods study in England and Northern Ireland to understand young men who have sex with men’s knowledge and attitudes towards human papillomavirus vaccination. BMJ Open. 9 (e025070) e025070. https://doi.org/10.1136/bmjopen-2018-025070

Targeted advertisement of chlamydia screening on social media: A mixed-methods analysis
Nadarzynski, T., Burton, Jack, Henderson, Kimberley, Zimmerman, Deborah, Hill, Orla and Graham, Cynthia 2019. Targeted advertisement of chlamydia screening on social media: A mixed-methods analysis. Digital Health. 5 205520761982719. https://doi.org/10.1177/2055207619827193

Determinants of influenza and pertussis vaccination uptake in pregnancy: a multi-centre questionnaire study of pregnant women and healthcare professionals
Wilcox, C.R., Calvert, A., Metz, J., Kilich, E., MacLeod, R., Beadon, K., Heath, P.T., Khalil, A., Finn, A., Snape, M.D., Vandrevala, T., Nadarzynski, T., Coleman, M.A. and Jones, C.E. 2019. Determinants of influenza and pertussis vaccination uptake in pregnancy: a multi-centre questionnaire study of pregnant women and healthcare professionals. The Pediatric Infectious Disease Journal. 38 (6), pp. 625-630. https://doi.org/10.1097/INF.0000000000002242

Attendance of MSM at Genitourinary Medicine services in England: implications for selective HPV vaccination programme (a short communication)
Bayley, J., Mesher, D., Nadarzynski, T., Hughes, G. and Soldan, K. 2018. Attendance of MSM at Genitourinary Medicine services in England: implications for selective HPV vaccination programme (a short communication). Sexually Transmitted Infections. 94, pp. 542-544. https://doi.org/10.1136/sextrans-2016-052912

Men who have sex with men who do not access sexual health clinics nor disclose sexual orientation are unlikely to receive the HPV vaccine in the UK
Nadarzynski, T., Smith, H., Richardson, D., Bremner, S. and Llewellyn, C. 2018. Men who have sex with men who do not access sexual health clinics nor disclose sexual orientation are unlikely to receive the HPV vaccine in the UK. Vaccine. 36 (33), pp. 5065-5070. https://doi.org/10.1016/j.vaccine.2018.06.075

Perceptions of HPV and attitudes towards HPV vaccination amongst men who have sex with men: A qualitative analysis
Nadarzynski, T., Smith, H., Richardson, D., Pollard, A. and Llewellyn, C.D. 2017. Perceptions of HPV and attitudes towards HPV vaccination amongst men who have sex with men: A qualitative analysis. British Journal of Health Psychology. 22 (2), pp. 345-361. https://doi.org/10.1111/bjhp.12233

Sexual healthcare professionals’ views on HPV vaccination for men in the UK
Nadarzynski, T., Smith, H.E., Richardson, D., Ford, E. and Llewellyn, C.D. 2015. Sexual healthcare professionals’ views on HPV vaccination for men in the UK. British Journal of Cancer. 113 (11), pp. 1599-1601. https://doi.org/10.1038/bjc.2015.403

Human papillomavirus and vaccine-related perceptions among men who have sex with men: a systematic review
Nadarzynski, T., Smith, H., Richardson, D., Jones, C.J. and Llewellyn, C.D. 2014. Human papillomavirus and vaccine-related perceptions among men who have sex with men: a systematic review. Sexually Transmitted Infections. 90 (7), pp. 515-523. https://doi.org/10.1136/sextrans-2013-051357