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Forensic awareness and the declining availability of firearms have resulted in an increase in the use of modified and re-activated firearms in crime. Although some modifications are undertaken to simply acquire a functioning firearm, others are perpetrated as a direct forensic countermeasure to prevent the association between a firearm and a crime. This article describes the effects of these modifications on bullet striation patterns imparted from the barrel to a fired bullet. The key results indicated that the investigated modifications display assessable characteristics. The use of an oversized barrel imparted striations consistent with firing with the absence of typical rifling. Subsequent or consecutively fired bullets possessed striation variations, with the first showing the least evidence of striations. The application of a choke resulted in more obvious bullet elongation compared to a smoothbore barrel. The restriction caused merging of lands and groves of the imparted rifling and obscured their usual definition. Effects of breech adaption were also characterised by observing the buckling and enlargement of the cartridge case. This deformity of the cartridge case was most evident when the barrel pressure increased due to the presence of the choke. From this study it was evident that unique characteristic impressions associated with different modifications most commonly found in criminal investigations can be utilised by a forensic expert and impart significant intelligence to an investigation. [ABSTRACT FROM AUTHOR]

UK post-exposure prophylaxis (PEP) guidelines were updated by the British Association for Sexual Health and HIV (BASHH) in 2011. In 2013, we changed policy to omit day 5 PEP follow-up at 56 Dean Street as it was felt clinically unnecessary. This audit compares our performance against BASHH standards for PEP attenders during June 2012 and June 2013. We identified 162 PEP prescriptions; PEP assessment and appropriate sexually transmitted infection testing was done well. PEP completion rates and post-PEP HIV testing were lower than BASHH standards. Following omission of day 5 review, documentation that results have been checked was poor; however, attendance at follow-up was not adversely affected. [ABSTRACT FROM AUTHOR]

We present a similar case but with the added variable of intense ultraviolet (UV) exposure secondary to sunbed use. This case thus further highlights the importance of UV protection in patients on systemic immunosuppression. [Extracted from the article]

Background/aim: In 2018, the European Medicines Agency strengthened warnings in relation to fluoroquinolone (FQ)-associated tendon injury. There is a lack of published data on FQs and tendon injury in an Irish context. The aim of the study was to investigate incidents and claims relating to FQs and tendon injury through an analysis of National Incident Management System (NIMS) data., Methods: The NIMS database was searched for incidents created between 1st June 2018 and 31st May 2023 which involved any FQ and referenced tendon injury. The incident data was analysed under predetermined field headings. NIMS was also searched for clinical claims involving any FQ with a Claim Finalised Date between 1st June 2018 and 31st May 2023. The claims were analysed to identify common themes., Results: The study identified 20 incidents which related to FQs and tendon injury, although only six reported an actual tendon injury. In 15 (75%) of the incidents, the prescription of a FQ was deemed inappropriate by the reporter. The study found four finalised claims, all of which related to bilateral Achilles tendon rupture following FQ exposure. In all four cases, the patient was aged over 60 and the injury occurred within days of commencing treatment., Conclusions: This study confirms that FQs continue to be prescribed inappropriately in high-risk patients and that incidents of tendon injury following FQ exposure continue to occur despite regulatory moves of raise awareness of this issue. Additional measures to minimise the risk of avoidable patient harm may be warranted., Competing Interests: Declarations. Conflict of interest: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Royal Academy of Medicine in Ireland.)

Background: Attempting to improve emergency care (EC) advanced clinical practitioner (ACP) training, Health Education England (HEE) South West (SW) implemented a pilot, whereby emergency departments (ED) were provided with enhanced funding and support to help ED consultants deliver teaching and supervision to EC ACPs to ensure more timely completion of EC ACP training compared with previous cohorts training in the region.We explored the experiences of trainee EC ACPs and consultant EC ACP leads working in EDs, which had implemented the new regional pilot., Methods: We used a qualitative design to conduct semi-structured interviews with trainee EC ACPs and consultant EC ACP leads across five EDs that had implemented the HEE SW pilot. Interview data were analysed thematically., Results: Twenty-five people were interviewed. We identified four themes: (1) the master's in advanced practice could be better aligned with the Royal College of Emergency Medicine credentialling e-portfolio; (2) EC ACP training needs some flexibility to reflect the individual-'one size does not fit all'; (3) supervision and teaching were recognised as important but requires significant staff capacity that is impacted by external pressures and (4) unclear role expectations and responsibilities hinder role transition and impact role identity.It was notable that EC ACPs primarily spoke about the development of their clinical skills both academically and within the workplace, despite there being other skills mentioned in the multiprofessional framework for advanced practice (leadership and management, education and research)., Conclusion: A clear supervision structure with protected time allocated for teaching and assessment of clinical skills within the ED is essential to facilitate trainee EC ACP progression. However, increasing demands on EDs make this a challenging goal to achieve. Role identity issues continue to persist despite the introduction of new guidance designed to provide more clarity around the ACP role., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2025. Re-use permitted under CC BY. Published by BMJ Group.)

Lay Abstract: Autistic play is generally described from a deficit perspective where the players themselves have been overlooked. It is important to consult with autistic children themselves about their understanding of play. We asked autistic children about their views on play using many different creative ways that were chosen by the children themselves. We analysed findings using reflexive thematic analysis. Autistic children in this research described play as involving feelings and emotions of pleasure and joy, autonomy and agency, playing by themselves and with others and engagement with materials and activities as meaningful. It is very important that we ask the players themselves what they think about play rather than relying on deficit framed, non-autistic definitions of autistic play. In this article, we will discuss how these findings will help develop future research, theory and practice in respecting children's right to authentic play experiences., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

This study investigated relationships between thin mental boundary functioning, creativity, imaginary companions (ICs), and anomalous '(entity) encounter experiences.' A convenience sample of 389 respondents completed the Revised Transliminality Scale, Oxford-Liverpool Inventory of Feelings and Experiences, Creative Experiences Questionnaire, Survey of Strange Events, and a measure of Childhood Imaginary Companions. Competing testing with path analysis found that the best-fitting model was consistent with the causal chain of 'Thin Boundaries (transliminality and schizotypy) → Creative Experiences → ICs → (Entity) Encounter Experiences.' These results suggest that deep-types of ICs (i.e., showing apparent independent agency) are perhaps most accurately characterized as syncretic cognitions versus hallucination-like experiences. The authors examine these findings relative to study limitations, as well as discussing the need for future research that approaches ICs as a special mental state that can facilitate allied altered-anomalous experiences. In this context, this study furthered understanding of relationships between conscious states related to mental boundaries, childhood imaginary companions, creative experiences, and entity encounters., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Introduction: Emergency doctors routinely face uncertainty-they work with limited patient information, under tight time constraints and receive minimal post-discharge feedback. While higher uncertainty tolerance (UT) among staff is linked with reduced resource use and improved well-being in various specialties, its impact in emergency settings is underexplored. We aimed to develop a UT measure and assess associations with doctor-related factors (eg, experience), patient outcomes (eg, reattendance) and resource use (eg, episode costs)., Methods: From May 2021 to February 2022, emergency doctors (specialty trainee 3 and above) from five Yorkshire (UK) departments completed an online questionnaire. This included a novel UT measure-an adapted Physicians' Reaction to Uncertainty scale collaboratively modified within our team according to Hillen et al 's (2017) UT model. The questionnaire also included well-being-related measures (eg, Brief Resilience Scale) and assessed factors like doctors' seniority. Patient encounters involving prespecified 'uncertainty-inducing' problems (eg, headache) were analysed. Multilevel regression explored associations between doctor-level factors, resource use and patient outcomes., Results: 39 doctors were matched with 384 patients. The UT measure demonstrated high reliability (Cronbach's α =0.92) and higher UT was significantly associated with better psychological well-being including greater resilience (Pearson's r=0.56; 95% CI=0.30 to 0.74) and lower burnout (eg, Cohen's d=-2.98; -4.62 to -1.33; mean UT difference for 'no' vs 'moderate/high' burnout). UT was not significantly associated with resource use (eg, episode costs: β=-0.07; -0.32 to 0.18) or patient outcomes including 30-day readmission (eg, OR=0.82; 0.28 to 2.35)., Conclusions: We developed a reliable UT measure for emergency medicine. While higher UT was linked to doctor well-being, its impact on resource use and patient outcomes remains unclear. Further measure validation and additional research including intervention trials are necessary to confirm these findings and explore the implications of UT in emergency practice., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.)

Objective: This scoping review aims to map and examine the extent and type of available evidence on health professionals' education accreditation within Africa., Introduction: The demand for health professionals is unprecedentedly high globally. One response to this challenge has been expanding training through more liberal education policies, facilitating private sector participation in education service provision. Some evidence suggests that this is a double-edged sword, increasing quantity but compromising the quality of health professionals produced. Regulation can provide a framework to assure and continuously improve quality, with such regulation in place in 79% of World Health Organization African countries. However, it is unclear how much and what evidence has been generated on how accreditation happens, where it is concentrated, and the prevailing evidence gaps within this region; therefore, we propose to conduct a scoping review., Inclusion Criteria: This review will include articles and dissertations focusing on the accreditation of health professionals' education in Africa. All methodological approaches and designs will be included. Conference abstracts and protocols will be excluded., Methods: This review will be carried out according to the JBI scoping review methodology. We conducted an initial search of CINAHL and MEDLINE to identify relevant articles. This informed our selection of keywords, along with index terms, to create a comprehensive search strategy for CINAHL (EBSCOhost), MEDLINE (Ovid), Global Health (Ovid), ERIC (EBSCOhost), Web of Science Core Collection, Embase, and Scopus. Sources included will be limited to those published starting from 2000 onwards. Data will be presented using tables and charts, accompanied by a narrative summary., Detail of This Review Project Can Be Found in Open Science Framework: https://doi.org/10.17605/OSF.IO/W5G7T., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on Behalf of JBI.)

Objective: Learning from adverse outcomes in health and social care is critical to advancing a culture of patient safety and reducing the likelihood of future preventable harm to service users. This review aims to present an overview of all clinical claims finalised in one calendar year involving publicly funded health and social care providers in Ireland., Design: This is a retrospective observational study. The Clinical Risk Unit (CRU) of the State Claims Agency identified all service-user clinical claims finalised between 1 January 2017 and 31 December 2017 from Ireland's National Incident Management System (n=713). Claims that had incurred financial damages were considered for further analysis (n=356). 202 claims underwent an in-depth qualitative review. Of these, 57 related to maternity and gynaecology, 64 to surgery, 46 to medicine, 20 to community health and social care and 15 related to children's healthcare., Results: The services of surgery and medicine ranked first and second, respectively, in terms of a number of claims. Claims in maternity services, despite ranking third in terms of claims numbers, resulted in the highest claims costs. Catastrophic injuries in babies resulting in cerebral palsy or other brain injury accounted for the majority of this cost.Diagnostic errors and inadequate or substandard communication, either with service users and/or interprofessional communication with colleagues, emerged as common issues across all clinical areas analysed. Quantitative analysis of contributory factors demonstrated that the complexity and seriousness of the service user's condition was a significant contributory factor in the occurrence of incidents leading to claims., Conclusion: This national report identifies common issues resulting in claims. Targeting these issues could mitigate patient safety risks and reduce the cost of claims., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Porous titanium scaffolds fabricated by powder bed fusion additive manufacturing techniques have been widely adopted for orthopedic and bone tissue engineering applications. Despite the many advantages of this approach, topological defects inherited from the fabrication process are well understood to negatively affect mechanical properties and pose a high risk if dislodged after implantation. Consequently, there is a need for further post-process surface cleaning. Traditional techniques such as grinding or polishing are not suited to lattice structures, due to lack of a line of sight to internal features. Chemical etching is a promising alternative; however, it remains unclear if changes to surface properties associated with such protocols will influence how cells respond to the material surface. In this study, we explored the response of bone marrow derived mesenchymal stem/stromal cells (MSCs) to Ti-6Al-4V whose surface was exposed to different durations of chemical etching. Cell morphology was influenced by local topological features inherited from the SLM fabrication process. On the as-built surface, topological nonhomogeneities such as partially adhered powder drove a stretched anisotropic cellular morphology, with large areas of the cell suspended across the nonhomogeneous powder interface. As the etching process was continued, surface defects were gradually removed, and cell morphology appeared more isotropic and was suggestive of MSC differentiation along an osteoblastic-lineage. This was accompanied by more extensive mineralization, indicative of progression along an osteogenic pathway. These findings point to the benefit of post-process chemical etching of additively manufactured Ti-6Al-4V biomaterials targeting orthopedic applications., (© 2024 The Authors. Journal of Biomedical Materials Research Part A published by Wiley Periodicals LLC.)

Background: Thoracolumbar transcutaneous spinal cord stimulation (tSCS) non-invasively evokes posterior root-muscle reflexes (PRMR) with the aim of neuromodulating sensorimotor function following spinal cord injury. Research is still in its infancy regarding the effect of body position on the nature of these spinally evoked responses. Therefore, the aim of this study was to investigate the influence of body position on the nature of PRMR responses during tSCS. Methods: A total of 11 (6M, 5F) participants completed a full PRMR recruitment curve from 10 ma up to 120 ma (10 ma increments) at the T11/12 intervertebral space using a singular 3.2 cm diameter cathode. At each intensity, three paired pulses (50 ms inter-pulse interval), followed by three singular pulses with a six-second delay were applied in each body position (supine, supine 90-90, sitting and standing) in a randomised order. The PRMR responses in lower limb muscles were recorded using wireless electromyographic sensors placed on the Soleus , Tibialis Anterior , Rectus Femoris and Bicep Femoris long head. A two-way (body position × muscle) repeated measures analysis of variance was used to investigate the effect of body position on PRMR-evoked responses. Results: There was a significant main effect of body position on PRMR resting motor threshold (RMT) ( p < 0.001), first response peak-to-peak amplitude ( p = 0.003) and percentage post-activation depression (%PAD) ( p = 0.012). Sitting had significantly higher RMT and significantly lower first response peak-to-peak amplitudes compared to all other positions, but significant differences in %PAD were only detectible between supine and standing. Conclusions: Body position influences the nature of PRMR-evoked responses during tSCS.

The NHS 111 service triages over 16,650,745 calls per year and approximately 48% of callers are triaged to a primary care disposition, such as a telephone appointment with a general practitioner (GP). However, there has been little assessment of the ability of primary care services to meet this demand. If a timely service cannot be provided to patients, it could result in patients calling 999 or attending emergency departments (ED) instead. This study aimed to explore the patient journey for callers who were triaged to a primary care disposition, and the ability of primary care services to meet this demand. We obtained routine, retrospective data from the Connected Yorkshire research database, and identified all 111 calls between the 1st January 2021 and 31st December 2021 for callers registered with a GP in the Bradford or Airedale region of West Yorkshire, who were triaged to a primary care disposition. Subsequent healthcare system access (111, 999, primary and secondary care) in the 72 hours following the index 111 call was identified, and a descriptive analysis of the healthcare trajectory of patients was undertaken. There were 56,102 index 111 calls, and a primary care service was the first interaction in 26,690/56,102 (47.6%) of cases, with 15,470/26,690 (58%) commenced within the specified triage time frame. Calls to 999 were higher in the cohort who had no prior contact with primary care (58% vs 42%) as were ED attendances (58.2% vs 41.8), although the proportion of avoidable ED attendances was similar (10.5% vs 11.8%). Less than half of 111 callers triaged to a primary care disposition make contact with a primary care service, and even when they do, call triage time frames are frequently not met, suggesting that current primary care provision cannot meet the demand from 111., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Pilbery et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Long waiting times in the ED have been shown to cause negative outcomes for patients. This study aims to assess the effect in reducing length of stay of (1) preventing low-acuity attenders from attending the ED and (2) diverting low-acuity attenders at triage to a colocated general practice (GP) service., Methods: Discrete event simulation was used to model a large urban teaching hospital in the UK, as a case study, with a colocated GP service. The Centre for Urgent and Emergency Care research database patient-level database (May 2015-April 2016), secondary literature and expert elicitation were used to inform the model. The model predicted length of stay, the percentage of patients being seen within 4 hours and the incremental cost-effectiveness of the colocated GP service., Results: The model predicted that diverting low-acuity patients to a colocated GP open 9:00 to 17:00 reduces the average time in the system for higher acuity attenders by 29 min at an estimated additional cost of £6.76 per patient on average. The percentage of higher acuity patients being seen within 4 hours increased from 61% to 67% due to the reduction in the length of stay of those who were in the ED for the longest time. However, the model is sensitive to changes in model inputs and there is uncertainty around ED activity durations, for which further primary data collection would be useful., Conclusion: Reducing the proportion of low-acuity attenders at the ED could have an impact on the time in the ED for higher acuity patients due to their use of shared resources, but is insufficient alone to meet current targets. The simulation model could be adapted for further analyses to understand which other changes would be needed to meet current government targets., Competing Interests: Competing interests: SC is an Emergency Medicine Expert Adviser for the Welsh and English Ombudsman., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.)

Background: The Sit-to-Stand (STS) transition is one of the most used activities of daily living and vital for independence. Neurological, or physical injuries impairing functional mobility or sensory feedback often require rehabilitative programs or therapeutic interventions. Understanding the biomechanical elements of daily movements and the interaction between these elements may help inform rehabilitation protocols and optimize targeted interventions, such as stimulation protocols., Research Question: What are the effects of different initial knee angle, arm facilitation and proprioceptive input on leg muscle activation patterns and balance during and after a sit-to-stand?, Methods: EMG of four lower limb muscles were recorded in 20 healthy participants as well centre-of-pressure sway amplitude and velocity, as participants stood from a seated position. Initial knee angles were set to various levels of extension (80°, 90°, 100°) and surface stability and arm facilitation were altered using a foam mat or crossing arms. Data were analysed across 3 phases of the STS transition., Results: More extended knee angles resulted in greater mediolateral sway during each phase (p < .01) and had a detrimental effect on anterior-posterior sway in phases 1 and 3. EMG data suggested more extended initial knee angles also increased EMG activity of the Tibialis Anterior (p < .001) and Bicep Femoris (p < .02) within Phases 1 and 2 to assist lift and stabilisation., Significance: Findings of this study outline phase-based muscle involvement as well as the compounding effects of reduced proprioceptive input and knee angle, on difficulty of the STS transition. Such results emphasising the need to take sensory and mobility issues into consideration when designing rehabilitative programs or stimulation control systems., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: People with serious mental illness experience worse physical health and greater mortality than the general population. Crude rates of A&E attendance and acute hospital admission are higher in people with serious mental illness than other hospital users. We aimed to further these findings by undertaking a standardised comparison of urgent and emergency care pathway use among users of mental health services and the general population., Methods: Retrospective cohort analysis using routine data from 2013-2016 from the CUREd dataset for urgent and emergency care contacts (NHS 111, ambulance, A&E and acute admissions) and linked mental health trust data for Sheffield, England. We compared annual age- and sex-standardised usage rates for each urgent and emergency care service between users of mental health services and those without a recent history of mental health service use., Results: We found marked differences in usage rates for all four urgent and emergency care services between the general population and users of mental health services. Usage rates and the proportion of users were 5-6 times and 3-4 times higher in users of mental health services, respectively, for all urgent and emergency care services. Users of mental health services were often more likely to experience the highest or lowest acuity usage characteristics., Conclusions: Current users of mental health services were heavily over-represented among urgent and emergency care users, and they made more contacts per-person. Higher service use among users of mental health services could be addressed by improved community care, more integrated physical and mental health support, and more proactive primary care. A complex pattern of service use among users of mental health services suggests this will need careful targeting to reduce avoidable contacts and optimise patient outcomes., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Lewis et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Medication adherence impacts health outcomes. Healthcare organisations implementing system-level interventions have potential for greater spread and sustainability than individual-level interventions. Within the integrated US Veterans Health Administration, a multidisciplinary team developed and evaluated a pilot quality improvement programme to assess the feasibility of automatic mailed prescription refills for patients with diabetes and low medication adherence (assessed by medication possession ratio <80%)., Methods: Patients were randomised to usual care with self-initiated refills versus automatic mailed refills for 6 months. Process outcomes included glycaemic control measures (HgbA1C), medication possession ratios for both automatic and self-initiated (reference) refills of medications, patient satisfaction and workforce effort (pharmacist time)., Results: Overall, 199 patients were randomised to automatic refills (n=99; 40 of whom participated) versus usual care (n=100). In multivariable analysis adjusting for baseline differences, after 6 months there was no difference in the proportion of patients with follow-up HgbA1C <8% (60.8% automatic refills vs 60.5% usual care, p=0.96). In the automatic refill group, the medication possession ratio for reference medicines was significantly higher than usual care (63.9% vs 54.5%, 95% CI (for difference) 3.1% to 15.9%, p<0.01)., Conclusions: Implications and lessons from this pilot programme include potential beneficial indirect effects from automatic medication refills on patient self-initiated refills of other medications; the importance of tailoring solutions to patient subgroups and specific adherence barriers; and recognition that the rapid deployment, iteration and evaluation of the project was facilitated by a multidisciplinary team embedded within an organisational learning health system., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Transcutaneous spinal cord stimulation (tSCS) at the cervical level may facilitate improved upper-limb function in those with incomplete tetraplegia. While clinical trials are ongoing, there is still much debate regarding the transmission pathway as well as appropriate stimulation parameters. This study aimed to explore the extent to which cervical tSCS can induce mono-synaptic reflexes in discrete upper-limb motor pools and examine the effects of altering stimulus location and intensity., Methods: Fourteen participants with intact nervous systems completed two laboratory visits, during which posterior root-muscle reflexes (PRMRs) were evoked via a 3 × 3 cathode matrix applied over the cervical spine. An incremental recruitment curve at the C7 vertebral level was initially performed to attain resting motor threshold (RMT) in each muscle. Paired pulses (1 ms square monophasic with inter-pulse interval of 50 ms) were subsequently delivered at a frequency of 0.25 Hz at two intensities (RMT and RMT + 20%) across all nine cathode positions. Evoked responses to the 1st (PRMR 1 ) and 2nd (PRMR 2 ) stimuli were recorded in four upper-limb muscles., Results: A significant effect of the spinal level was observed in all muscles for PRMR 1 , with greater responses being recorded caudally. Contralateral stimulation significantly increased PRMR 1 in Biceps Brachii ( p < 0.05, F = 4.9, η2 = 0.29), Flexor Carpi Radialis ( p < 0.05, F = 4.9, η2 = 0.28) and Abductor Pollicis Brevis ( p < 0.01, F = 8.9, η2 = 0.89). Post-activation depression (PAD) was also significantly increased with contralateral stimulation in Biceps Brachii ( p = 0.001, F = 9.3, η2 = 0.44), Triceps Brachii ( p < 0.05, F = 5.4, η2 = 0.31) and Flexor Carpi Radialis ( p < 0.001, F = 17.4, η2 = 0.59)., Conclusions: A level of unilateral motor pool selectivity may be attained by altering stimulus intensity and location during cervical tSCS. Optimising these parameters may improve the efficacy of this neuromodulation method in clinical cohorts.

Caenorhabditis elegans larvae display developmental plasticity in response to environmental conditions: in adverse conditions, second-stage larvae enter a reversible, long-lived dauer stage instead of proceeding to reproductive adulthood. Dauer entry interrupts vulval induction and is associated with a reprogramming-like event that preserves the multipotency of vulval precursor cells (VPCs), allowing vulval development to reinitiate if conditions improve. Vulval induction requires the LIN-3/EGF-like signal from the gonad, which activates EGFR-Ras-ERK signal transduction in the nearest VPC, P6.p. Here, using a biosensor and live imaging we show that EGFR-Ras-ERK activity is downregulated in P6.p in dauers. We investigated this process using gene mutations or transgenes to manipulate different steps of the pathway, and by analyzing LET-23/EGFR subcellular localization during dauer life history. We found that the response to EGF is attenuated at or upstream of Ras activation, and discuss potential membrane-associated mechanisms that could achieve this. We also describe other findings pertaining to the maintenance of VPC competence and quiescence in dauer larvae. Our analysis indicates that VPCs have L2-like and unique dauer stage features rather than features of L3 VPCs in continuous development., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)