Endovascular therapy is the main treatment for chronic limb-threatening ischaemia in the UK. Despite a restenosis risk of 50% over 2 years, reintervention rates are low, potentially resulting in preventable amputations. European guidelines recommend ultrasound surveillance to facilitate early treatment of restenosis. This study will investigate the use of duplex ultrasound after endo revascularisation (DUSTER). The aim is to assess the feasibility, acceptability and impact on clinical decision-making of a 1-year integrated ultrasound surveillance programme after lower limb endovascular therapy.

DUSTER is a mixed-methods study. Phase I is a three-site, feasibility, open-label, randomised controlled trial. The standard of care, the control arm, is standard clinical surveillance by a vascular specialist at 1, 6 and 12 months. The intervention arm will receive integrated ultrasound (ankle-brachial pressure index, toe pressure and duplex) plus standard clinical surveillance. Primary outcomes are rates of attendance and completion of ultrasound surveillance tests, as well as the percentage of participants undergoing reintervention for restenosis. Secondary outcomes are limb salvage, amputation-free survival, reasons for amputation, complications, serious adverse events and mortality.

Phase II comprises independent semistructured interviews with intervention arm participants. The interviews will explore barriers and facilitators to ultrasound surveillance and the effect of ultrasound surveillance on patients’ lives.

Phase III has two separate focus groups for participants and clinical stakeholders to identify which outcomes matter most in any subsequent large-scale effectiveness trials.

This research has been approved by a UK (West Midlands, Black Country) Research Ethics Committee (reference 24/WM/0232) and the Health Research Authority (IRAS 349192). Dissemination of results will be by the DUSTER co-investigators in peer-reviewed journals, to the National Institute for Health and Care Research and to a lay audience via the Mid and South Essex NHS Foundations Trust website.

NCT06702306.

Young people (YP) whose parents have depression are at elevated risk for developing depression themselves and could benefit from preventive interventions. However, when parents are in a depressive episode, this reduces the effects of psychological interventions for depression in YP. Moreover, parental depression is often managed suboptimally in usual care. There is, therefore, a case for identifying and optimising parental depression treatment to enhance the effectiveness of psychological preventive interventions for depression in YP.

This is a randomised controlled trial (Skills for adolescent WELLbeing) to determine the effectiveness of a cognitive behavioural therapy (CBT) intervention compared with usual care in increasing the time to a major depressive episode in YP by 9-month follow-up (primary outcome). The intervention offers a 12-week treatment-optimisation phase for parents depressed at study entry, followed by randomisation of the young person to a small group manualised online CBT programme facilitated by a therapist. YP allocated to the intervention will receive eight weekly sessions plus three monthly continuation sessions. Secondary outcomes include the number of depression-free weeks, mental health symptoms and functioning. Mechanisms of intervention action will be assessed with mediation analysis of quantitative data and thematic analysis of qualitative interviews. Participants (parents/carers with depression and their children aged 13–19 years) will be identified through existing cohorts of adults with depression, from primary care through health boards in Wales and England, UK, schools and advertising including via social media.

The trial has received ethical approval from Wales NHS Research Ethics Committee (REC) 5, the Health Research Authority and Health and Care Research Wales (IRAS 305331; REC 22/WA/0254). This manuscript is based on V.5.7 of the protocol (17 January 2025). Findings will be disseminated in peer-reviewed journals and conferences. Reports and social media messages will be used to disseminate findings to the wider public.

ISRCTN13924193 (date registered: 15 March 2023).