20. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.INTRODUCTION Autologous T-cells transduced to express a chimeric antigen receptor (CAR) directed against CD19 elicit high response rates in relapsed or refractory (r/r) B-cell non-Hodgkin lymphoma (B-NHL). However, r/r B-NHL remissions are durable in fewer than half of recipients of second-generation CAR T-cells. Third-generation (3G) CARs employ two costimulatory domains, resulting in improved CAR T-cell efficacy in vitro and in animal models in vivo. This investigator-initiated, phase I dose escalation trial, termed ENABLE, will investigate the safety and preliminary efficacy of WZTL-002, comprising autologous T-cells expressing a 3G anti-CD19 CAR incorporating the intracellular signalling domains of CD28 and Toll-like receptor 2 (TLR2) for the treatment of r/r B-NHL. METHODS AND ANALYSIS Eligible participants will be adults with r/r B-NHL including diffuse large B-cell lymphoma and its variants, follicular lymphoma, transformed follicular lymphoma and mantle cell lymphoma. Participants must have satisfactoesults will be reported in a peer-reviewed journal, and results presented at scientific conferences or meetings. TRIAL REGISTRATION NUMBER NCT04049513. © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.INTRODUCTION Adolescents with type 1 diabetes are at a higher risk of developing psychiatric disorders, particularly eating disorders, compared with their healthy peers. In turn, this increases the risk for sub-optimal glycaemic control and life-threatening diabetes-related complications. Despite these increased risks, standard diabetes care does not routinely provide psychological support to help prevent or reduce mental health risks. There is an urgent need to develop 'clinically usable' psychosocial interventions that are acceptable to patients and can be realistically integrated into clinical care. This study aims to examine the feasibility and acceptability of a brief self-compassion intervention for adolescents with type 1 diabetes and disordered eating behaviour. METHODS AND ANALYSIS This feasibility study will examine the effectiveness of a brief self-compassion intervention, compared with a waitlist control group. Participants aged 12-16 years will be recruited from three diabetes outpatient clinics rmissions. Published by BMJ.INTRODUCTION Hospitals are complex systems and optimising their function is critical to the provision of high quality, cost effective healthcare. Metrics of performance have to date focused on the performance of individual elements rather than the whole system. Manipulation of individual elements of a complex system without an integrative understanding of its function is undesirable and may lead to counterintuitive outcomes and a holistic metric of hospital function might help design more efficient services. OBJECTIVES We aimed to use network analysis to characterise the structure of the system of perioperative care for emergency surgical admissions in our tertiary care hospital. DESIGN We constructed a weighted directional network representation of the emergency surgical services using patient location data from electronic health records. SETTING A single-centre tertiary care hospital in the UK. PARTICIPANTS We selected data from the retrospective electronic health record data of all unplanned admissions with a surgical intervention during their stay during a 3.5-year period, which resulted in a set of 16 500 individual admissions. METHODS We then constructed and analysed the structure of this network using established methods from network science such as degree distribution, betweenness centrality and small-world characteristics. RESULTS The analysis showed the service to be a complex system with scale-free, small-world network properties. We also identified such potential hubs and bottlenecks in the system. CONCLUSIONS Our holistic, system-wide description of a hospital service may provide tools to inform service improvement initiatives and gives us insights into the architecture of a complex system of care. The implications for the structure and resilience of the service is that while being robust in general, the system may be vulnerable to outages at specific key nodes. © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.INTRODUCTION Large cystic osteochondral lesions of the talus (OLTs) have been shown to have inferior clinical outcomes after reparative techniques such as bone marrow stimulation. Autologous osteochondral transplantation has been viewed as an alternative choice for treating these lesions, but donor-site morbidity has limited its application. Excellent clinical outcomes have been shown in repairing these types of lesions with autologous osteoperiosteal grafts, and these outcomes are achieved at a low cost and without donor-site morbidity in the normal knee joint. This will be the first randomised controlled trial to compare the two surgical techniques, and recommendations for the treatment of patients with large cystic OLTs will be provided. METHODS AND ANALYSIS A non-inferiority randomised controlled trial will be conducted. A total of 70 participants with clinically diagnosed large cystic OLTs will be randomly allocated to either the experimental group or the control group at a ratio of 11. The experimental DISSEMINATION The current study was approved by the board of research ethics of Peking University Third Hospital Medical Science Research Ethics Committee. The results of this study will be presented at national and international conferences and published in peer-reviewed journals. TRIAL REGISTRATION NUMBER NCT03347877. Tamoxifen © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.OBJECTIVES To explore weight perceptions in a large, nationally representative sample of older adults, and the extent to which they differ according to age and perceived health status. SETTING England. PARTICIPANTS 5240 men and women (≥50 years old) participating in the English Longitudinal Study of Ageing (2016/2017). MAIN OUTCOME MEASURES Weight perception was self-reported as too heavy, too light or about right. RESULTS The majority of older adults endorsed a weight perception that matched their (objectively measured) body mass index (BMI) classification. However, 1 in 10 (9.9%) older adults classified by BMI as normal weight (18.5-24.9 kg/m2) felt too light, with women at the upper end of the older age spectrum (OR=1.04, 95% CI 1.01 to 1.09), and men (OR=3.70, 95% CI 1.88 to 7.28) and women (OR=2.61, 95% CI 1.27 to 5.35) in poorer health more likely to do so. Almost half (44.8%) of older adults classified as overweight (25-29.9 kg/m2) and 1 in 10 (10.3%) classified as obese (≥30 kg/m2) felt about the right weight, with this observed more frequently among men and women at the upper end of the older age spectrum (OR range 1.