Sex workers evaluate reporting violence
| ISRCTN | ISRCTN56423125 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN56423125 |
| ClinicalTrials.gov (NCT) | Nil known |
| Clinical Trials Information System (CTIS) | Nil known |
| Protocol serial number | NIHR156812 |
| Sponsor | London School of Hygiene & Tropical Medicine |
| Funder | National Institute for Health and Care Research |
- Submission date
- 03/07/2025
- Registration date
- 03/09/2025
- Last edited
- 26/11/2025
- Recruitment status
- Recruiting
- Overall study status
- Ongoing
- Condition category
- Other
Plain English summary of protocol
Background and study aims
Sex-worker communities and services have developed ways to prevent violence and support survivors but we don’t know enough about what works best to improve sex workers’ safety and mental health. Some sex workers are vulnerable to violence, have unmet mental health needs and don’t have access to appropriate services. In London, 36-73% of sex workers have been attacked by clients, 7-42% by police officers, 18-56% by partners, and 17-67% by others, and 35% -71% have anxiety or depression; the highest figures are for women who work on the street. One in four sex workers advertising online report fraud and robbery, stalking and harassment. Despite this, sex workers are often discriminated against by police and services and their reports of violence not acted on.
UK charity National Ugly Mugs (NUM) receives reports of violence and other crimes against sex workers and uses this information to develop alerts. NUM circulates these alerts by text and email to sex workers, venues and services signed up to the service, to raise awareness about people and situations that pose a threat to sex workers. NUM has a national database of violence and other crimes (e.g. theft, fraud) against sex workers which they can use to screen potential clients (by their contact details, profile names, vehicle registrations) using an online tool ‘NUMchecker’. NUM also offers ‘casework’ to survivors of violence, including emergency support, help with mental health, alcohol and other drug problems, as well as accessing other health and welfare services. If the individual wants to, NUM supports them in reporting incidences of harms to the police and court, although many choose to avoid criminal justice services because of widespread mistreatment by police.
The Sex Workers Evaluate Reporting Violence (SWERV!) project uses participatory, mixed-methods, to evaluate how NUM’s services affect sex workers’ safety and mental health, with sex workers centrally involved in designing and carrying out the research. We are registering one component of our study, work-package C, that measures the extent to which violence prevention tools delivered by NUM reduces violent incidences towards sex workers, supports better mental health and access to services.
Who can participate?
Anyone aged 18 years or older who are members of NUM and/or have been involved in sex work in the last 6 months.
What does the study involve?
We will ask participants newly enrolled into NUM, and sex workers who aren’t members, to fill in a questionnaire twice, six months apart. The questionnaire will ask about violence, safety strategies, and mental health. We will compare the experiences of sex workers who do and don’t use the alerts and NUMchecker. Other components of the study involves interviewing sex workers (who have and haven’t used NUM) and service providers about their views and experiences of NUM’s services and the consequences they’ve had, to understand who benefits from the interventions, how and why. We will estimate value for money, by calculating how much the interventions cost to run and comparing this to no intervention, in terms of preventing violence and improving quality of life. We will use the study information to build up a picture on how NUM’s services work in different places and for different people, depending on their circumstances and the wider environment. We developed this proposal with sex worker-led organisations across the UK and participatory methods are at the heart of our work. This means sex workers are centrally involved (as researchers and through discussion workshops) in designing and carrying out the research. Together we will use what we learn, to recommend how to improve community-based violence prevention and survivor support services for and by sex workers.
What are the possible benefits and risks of participating?
There may not be any direct benefit to participants from taking part in this research, other than compensation for their time. Our overall aim is that this study will improve violence prevention tools and survivor support services for people working in the sex industry and so this might be of benefit to participants and/or people they know in the future.
The main risk to participants in this study is that discussing experiences of violence, trauma and abuse as well as mental health and sex work may be difficult, upsetting or triggering. So, we have signposted several support services and organisations for participants to access if they need to.
Where is the study run from?
London School of Hygiene and Tropical Medicine (UK), National Ugly Mugs and University of Brunel Our team has expertise in service-delivery with sex workers, epidemiology, social sciences, evaluation and economics and strong links with sex working communities.
When is the study starting and how long is it expected to run for?
December 2023 to December 2026
Who is funding the study?
National Institute for Health and Care Research (NIHR) (UK).
Who is the main contact?
Professor Lucy Platt (lucy.platt@lshtm.ac.uk)
Dr Pippa Grenfell (pippa.grenfell@lshtm.ac.uk)
Dr Raven Bowen (raven@nationaluglymugs.org)
Contact information
Public, Scientific, Principal investigator
15-17 Tavistock Place
London
WC1H 9SH
United Kingdom
 ORCID ID |
0000-0002-0943-0045 |
|---|---|
| Phone | +44 (0)20 7636 8636 |
| lucy.platt@lshtm.ac.uk |
Public, Scientific, Principal investigator
15-17 Tavistock Place
London
WC1H 9SH
United Kingdom
| ORCID ID |
0000-0003-0917-7980 |
|---|---|
| Phone | +44 (0)20 7636 8636 |
| pippa.grenfell@lshtm.ac.uk |
Study information
| Primary study design | Observational |
|---|---|
| Study design | Multi-centred observational cohort study with qualitative process evaluation, framed by a participatory approach |
| Secondary study design | Longitudinal study |
| Participant information sheet | ISRCTN56423125 WP C Consent form_v2 01May25.pdf |
| Scientific title | Violence prevention and survivor support for and by sex workers: evaluation of a community-based intervention |
| Study acronym | SWERV |
| Study objectives | Aim: Evaluate the implementation, impact, cost and cost-effectiveness of a community-based violence prevention and survivor support service on sex workers’ safety, mental health, and access to services. Objectives: 1. Measure the effect of violence prevention tools (alerts/NUMchecker) on sex workers’ safety (including working strategies) and mental health (WP A, C) 2. Explore mechanisms through which violence prevention tools affect sex workers’ safety and mental health (WP A, B) 3. Explore mechanisms and related contexts through which survivor support (casework) affects sex workers’ mental health, access to and experience of services (e.g. health, welfare) (WP A, B) 4. Develop and test a theory of change, comprising context-mechanism-outcome configurations, to understand how the interventions (alerts/NUMchecker, reporting, casework) work, for whom, where and under what conditions (WP A–C) 5. Evaluate the acceptability, accessibility, fidelity and equity of the interventions (WP B, C) 6. Understand how NUM’s engagement with services and police, via casework, affects: a) reporting of violence to NUM b) uptake of alerts and NUMchecker c) sex workers’ access to services (WP B) 7. Identify priority health and wellbeing outcomes of NUM’s violence prevention and survivor support service, from sex workers’ perspectives (WP B) 8. Estimate the cost of alerts, NUMchecker and survivor support (casework) (WP D) 9. Estimate the cost-effectiveness of use of alerts and NUMchecker (vs. no intervention) to prevent an episode of violence and cost per QALY (WP D) 10. Co-produce with sex workers and practitioners the study design, theory of change and recommendations to improve community alerts, reporting and casework, for use by NUM and other services in the UK and elsewhere (WP A, E) |
| Ethics approval(s) |
Approved 03/11/2024, London School of Hygiene and Tropical Medicine Research Ethics Committee (Keppel Street, London, WC1E7HT, United Kingdom; +44 (0) 207 636 8636; ethics@lshtm.ac.uk), ref: 30275 |
| Health condition(s) or problem(s) studied | Violence prevention and survivor support for and by sex workers |
| Intervention | National Ugly Mugs (NUM) is a violence prevention and survivor support for and by sex workers. NUM aims to improve rights, safety and inclusion of sex workers by facilitating sex workers to make decisions about their own safety, support survivors of sex worker to manage consequence of violence and seek justice (if desired), and by influencing local and national policy that shapes context in which sex work operates. We will evaluate four aspects of NUM’s violence prevention and survivor support: (1) community alerts about violent perpetrators; (2) community-based violence reporting system; (3) NUMchecker tool allowing sex workers to screen clients (by contact details, profile names and vehicle registration) against national database; and (4) casework for survivors of violence and linked engagement with referral services. We will use a participatory mixed-method, quasi-experimental design, informed by realist evaluation principles and the ‘DEPTH approach’, using dialogues with communities and practitioners to co-produce action-oriented research. There are five work packages (WP): (A) first dialogues and mapping, including a rapid evidence review; (B) qualitative and quantitative process evaluation; (C) impact evaluation (pre and post cohort study with non-equivalent comparison group) measuring self-reported data on violence and mental health; (D) economic evaluation comprising costing of interventions and cost-effectiveness analysis; and (E) second dialogues and research into action |
| Intervention type | Behavioural |
| Primary outcome measure(s) |
The primary outcome for evaluating the impact of violence prevention interventions (alerts and NUMchecker) is self-reported violence in the last 6 months (enacted, threatened or attempted) by clients, other parties at work, police. This is defined as physical, including sexual, and emotional violence. Physical violence encompasses direct attack (being hit, attacked with a weapon or kidnapped) as well as theft, spiking (e.g. drugs put into drink), damage to personal property. Emotional violence includes verbal abuse (being belittled, humiliated, having abusive or insulting language such as racist remarks directed at you), being outed as a sex worker, stalking (online or in person). Sexual violence includes forced sex; touched against one’s will, removal of condom, and forced/tricked into providing a sexual service (e.g. unprotected sex) without consent or payment. |
| Key secondary outcome measure(s) |
Secondary outcomes include intermediate outcomes such as fear of violence, adapted working strategies (cancellation and/or avoidance of clients; client screening, working with others, use of CCTV/security); awareness of reporting systems/support services, contact with services (sex worker specific/mental health/housing, drug treatment, welfare services). Longer-term outcomes include mental health - depression and anxiety and self-rated health measures (e.g. PHQ4, EQ5D-5L) that have been well validated in UK primary care and among sex workers and homeless populations including by our team. |
| Completion date | 01/12/2026 |
Eligibility
| Participant type(s) | Population |
|---|---|
| Age group | Mixed |
| Lower age limit | 18 Years |
| Upper age limit | 70 Years |
| Sex | All |
| Target sample size at registration | 600 |
| Key inclusion criteria | 1. Be aged 18 years of age or older 2. Have sold sex in the last 6 months defined as received money in exchange for in person sexual service 3. Have sold sex in a city in the last 6 months (for example, Birmingham, Bristol, Brighton, Manchester, London, Glasgow, Hull) 4. Have capacity to consent 5. Be a new NUM member (defined as registered into NUM within the past 7 days) 6. Provide in-person sexual services 7. Work predominantly as an indoor sex worker |
| Key exclusion criteria | 1. Under 18 years 2. In secure services 3. Lack capacity to consent 4. Who do have not recent experience of selling in-person sexual services |
| Date of first enrolment | 28/06/2025 |
| Date of final enrolment | 17/12/2025 |
Locations
Countries of recruitment
- United Kingdom
- England
- Scotland
- Wales
Study participating centre
Manchester
M4 1LE
England
Results and Publications
| Individual participant data (IPD) Intention to share | No |
|---|---|
| IPD sharing plan summary | Not expected to be made available |
| IPD sharing plan |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | Work package C consent form version 2 |
01/05/2025 | 26/11/2025 | No | Yes |
| Participant information sheet | Work package C participant information sheet version 4 |
18/09/2025 | 26/11/2025 | No | Yes |
| Protocol file | version 2 | 18/09/2025 | 26/11/2025 | No | No |
| Study website | 11/11/2025 | 11/11/2025 | No | No | |
| Study website | Study website | 11/11/2025 | 11/11/2025 | No | Yes |
Additional files
- ISRCTN56423125 Protocol v2 18.09.25.pdf
- Protocol file
- ISRCTN56423125 WP C Consent form_v2 01May25.pdf
- Work package C consent form
- ISRCTN56423125 WP C Information sheet - V4_18Sep25.pdf
- Work package C participant information sheet
Editorial Notes
26/11/2025: The following changes were made to the study record:
1. Uploaded protocol (not peer-reviewed) as an additional file.
2. The participant information sheets was uploaded as additional files.
3. The Completion date was changed from 01/05/2026 to 01/12/2026
4. The Date of final enrolment was changed from 28/11/2025 to 17/12/2025
04/07/2025: Trial's existence confirmed by London School of Hygiene and Tropical Medicine Research Ethics Committee.
