Optimising ambulance conveyance rates and staff costs by adjusting proportions of rapid-response vehicles and dual-crewed ambulances: an economic decision analytical modelling study.

AIM: To model optimum proportions of dual-crewed ambulances (DCAs) and rapid-response vehicles (RRVs) in Ambulance Trusts with a view to generating a policy brief for one Ambulance Trust and a modelling tool for other Trusts on the strategic procurement and allocation of emergency vehicle (EV) resources. METHODS: Historical EV assignments for 12 months of emergency calls in 2019 were provided by an NHS Ambulance Trust and analysed for backup, see and treat, and patient to hospital conveyance. Unit costs were derived for paramedics and technicians using Agenda for Change pay rates. Time cycles were assigned for RRV and DCA attendances and unit costs assigned to these. Information was put into a decision analytical model to estimate the costs and numbers of vehicles attending incidents based on relative proportions of available RRVs and DCAs. RESULTS: Of 711 992 calls attended by 837 107 EVs, 514 766 (72.3%) required at least one emergency department conveyance. The rate of conveyance was significantly lower when RRVs arrived first on the scene. 27 883 out of 529 693 (5.3%) DCAs first arriving at an incident required some backup, and this was also factored into the model. Modelling demonstrated high conveyance rates were counterproductive when increasing the relative proportions of RRVs to DCAs. For example, with conveyance rates of 65%, increasing the RRVs increased the cost and numbers of vehicles attending per incident. At lower conveyance rates, however, there was a levelling around 30% where it could become cost-effective to increase the relative proportions of RRVs to DCAs. CONCLUSION: At current overall conveyance rates, there is no benefit in increasing the relative proportions of RRVs to DCAs unless additional benefits can be realised that bring the conveyance rates down.

Improving ambulance care for children suffering acute pain: a qualitative interview study.

BACKGROUND: Pain is a highly complex sensory and emotional experience. When a child suffers acute pain through illness or injury, they are often transported to hospital by ambulance. Pre-hospital pain management in children is poor, with 61% of children receiving suboptimal pain management. Consequences of poor pain management include the risk of developing post-traumatic stress disorder and altered pain perception. We aimed to identify clinicians' perceptions of barriers, facilitators and potential improvements for the management of pre-hospital acute pain in children. METHODS: Qualitative face to face semi-structured recorded interviews were performed in one large UK ambulance service. Audio files were transcribed verbatim with thematic analysis used to generate themes. NVivo 12 was used to support data analysis. Findings were combined with existing evidence to generate a driver diagram. RESULTS: Twelve ambulance clinicians participated, including 9 registered paramedics and 3 emergency medical technicians. Median (IQR) age was 43.50 (41.50, 45.75) years, 58% were male, median (IQR) experience was 12 (4.25, 15.50) years and 58% were parents. Several themes relating to barriers and facilitators were identified, including physical, emotional, social, organisational, environmental, management, knowledge and experience. Improvement themes were identified relating to management, organisation and education. These data were combined to create a driver diagram; the three primary drivers were 1) explore methods to increase rates of analgesic administration, including utilising intranasal or inhaled routes; 2) reduce fear and anxiety in children, by using child friendly uniform, additional non-pharmacological techniques and more public interaction and 3) reduce fear and anxiety in clinicians, by enhancing training and optimising crew mix. CONCLUSIONS: The quality of care that children receive for acute pain in the ambulance service may be improved by increasing rates of analgesic administration and reducing the fear and anxiety experienced by children and clinicians. Future research involving children and parents would be useful to determine the most important outcome measures and facilitate intervention development.

Ambulance clinician perspectives of disparity in prehospital child pain management: A mixed methods study.

BACKGROUND: When children suffer acute pain, the ambulance service is often involved to provide initial assessment, treatment, and transport. Several predictors of effective pain management have been identified, including children who are younger (0-5 years), administered analgesics, and living in homes from more affluent areas. OBJECTIVE: To explain previously identified predictors of effective prehospital pain management in children. DESIGN: Mixed methods sequential explanatory study. SETTING AND PARTICIPANTS: East Midlands Ambulance Service National Health Service Trust paramedics and emergency medical technicians (EMTs) participated in face-to-face semi-structured interviews. These were audio recorded, transcribed verbatim, and coded using thematic analysis. Meta-inferences were generated and illustrated within a joint display. RESULTS: Twelve clinicians (9 paramedics and 3 EMTs) were interviewed. Median (interquartile range) age was 43.5 years (41.5, 45.75), 58% were male (n = 7) and 58% were parents (n = 7). Possible explanations were provided for all predictors. Younger children were perceived to express more emotion, were easier to distract, and lived more in the moment than their older counterparts, which explained why younger children were more likely to achieve effective pain management. Analgesics were perceived to have a psychosocial benefit in addition to the pharmacological action. Ambulance clinicians felt that children living in more affluent areas were more likely to achieve effective pain management because the kempt environment facilitated assessment and management and clinicians spent more time on scene; this allowed more time for analgesics to take effect. Participants perceived paramedics to be more confident, and it was found that paramedics were older, more experienced, had a greater scope of practice, and spent more time on scene than EMTs. CONCLUSION: Prehospital pain management in children could be improved by facilitating and prioritizing analgesic administration and by ambulance services ensuring a paramedic, or highly trained clinician, is present on each vehicle, necessitating long-term commitment to staff development.

Mixed methods in pre-hospital research: understanding complex clinical problems.

Healthcare is becoming increasingly complex. The pre-hospital setting is no exception, especially when considering the unpredictable environment. To address complex clinical problems and improve quality of care for patients, researchers need to use innovative methods to create the necessary depth and breadth of knowledge. Quantitative approaches such as randomised controlled trials and observational (e.g. cross-sectional, case control, cohort) methods, along with qualitative approaches including interviews, focus groups and ethnography, have traditionally been used independently to gain understanding of clinical problems and how to address these. Both approaches, however, have drawbacks: quantitative methods focus on objective, numerical data and provide limited understanding of context, whereas qualitative methods explore more subjective aspects and provide perspective, but can be harder to demonstrate rigour. We argue that mixed methods research, where quantitative and qualitative methods are integrated, is an ideal solution to comprehensively understand complex clinical problems in the pre-hospital setting. The aim of this article is to discuss mixed methods in the field of pre-hospital research, highlight its strengths and limitations and provide examples. This article is tailored to clinicians and early career researchers and covers the basic aspects of mixed methods research. We conclude that mixed methods is a useful research design to help develop our understanding of complex clinical problems in the pre-hospital setting.

Predictors of effective management of acute pain in children within a UK ambulance service: A cross-sectional study.

OBJECTIVE: We aimed to identify predictors of effective management of acute pain in children in the pre-hospital setting. METHODS: A retrospective cross-sectional study using electronic clinical records from one large UK ambulance service during 01-Oct-2017 to 30-Sep-2018 was performed using multivariable logistic regression. We included all children <18 years suffering acute pain. Children with a Glasgow Coma Scale score of <15, no documented pain or without a second pain score were excluded. The outcome measure was effective pain management (abolition or reduction of pain by ≥2 out of 10 using the numeric pain rating scale, Wong-Baker FACES® scale or FLACC [face, legs, activity, crying and consolability] scale). RESULTS: 2312 patients were included for analysis. Median (IQR) age was 13 (9-16), 54% were male and the cause of pain was trauma in 66% of cases. Predictors of effective pain management include children who were younger (0-5 years) compared to older (12-17 years) (adjusted odds ratio [AOR] 1.53; 95% confidence interval [CI] 1.18-1.97), administered analgesia (AOR 2.26; CI 1.87-2.73), attended by a paramedic (AOR 1.46; CI 1.19-1.79) or living in an area of low deprivation (index of multiple deprivation [IMD] 8-10) compared to children in an area of high deprivation (IMD 1-3) (AOR 1.37; CI 1.04-1.80). Child sex, type of pain, transport time, non-pharmacological treatments and clinician experience were not significant. CONCLUSION: These predictors highlight disparity in effective pre-hospital management of acute pain in children. Qualitative research is needed to help explain these findings.

What are the predictors, barriers and facilitators to effective management of acute pain in children by ambulance services? A mixed-methods systematic review protocol.

INTRODUCTION: The management of pain is complex, especially in children, as age, developmental level, cognitive and communication skills and associated beliefs must be considered. Without effective pain treatment, children may suffer long-term changes in stress hormone responses and pain perception and are at risk of developing posttraumatic stress disorder. Pre-hospital analgesic treatment of injured children is suboptimal, with very few children in pain receiving analgesia. The aim of this review is to identify predictors, barriers and facilitators to effective management of acute pain in children by ambulance services. METHODS: A mixed-methods approach has been adopted due to the research question lending itself to qualitative and quantitative inquiry. The segregated methodology will be used where quantitative and qualitative papers are synthesised separately, followed by mixed-methods synthesis (meta-integration). We will search from inception: MEDLINE, CINAHL and PsycINFO via EBSCOHost, EMBASE via Ovid SP, Web of Science and Scopus. The Cochrane Library, the Joanna Briggs Institute, PROSPERO, ISRCTN and ClinicalTrials.gov will be searched. We will include empirical qualitative and quantitative studies. We will exclude animal studies, reviews, audits, service evaluations, simulated studies, letters, Best Evidence Topics, case studies, self-efficacy studies, comments and abstracts. Two authors will perform full screening and selection, data extraction and quality assessment. GRADE and CERQual will determine the confidence in cumulative evidence. DISCUSSION: If confidence in the cumulative evidence is deemed Moderate, Low or Very Low, then this review will inform the development of a novel mixed-methods sequential explanatory study which aims to comprehensively identify predictors, barriers and facilitators to effective pain management of acute pain in children within ambulance services. Future research will be discussed among authors if confidence is deemed High.Systematic Review Registration: PROSPERO: CRD42017058960.

Adaptation of Chain Event Graphs for use with Case-Control Studies in Epidemiology.

Case-control studies are used in epidemiology to try to uncover the causes of diseases, but are a retrospective study design known to suffer from non-participation and recall bias, which may explain their decreased popularity in recent years. Traditional analyses report usually only the odds ratio for given exposures and the binary disease status. Chain event graphs are a graphical representation of a statistical model derived from event trees which have been developed in artificial intelligence and statistics, and only recently introduced to the epidemiology literature. They are a modern Bayesian technique which enable prior knowledge to be incorporated into the data analysis using the agglomerative hierarchical clustering algorithm, used to form a suitable chain event graph. Additionally, they can account for missing data and be used to explore missingness mechanisms. Here we adapt the chain event graph framework to suit scenarios often encountered in case-control studies, to strengthen this study design which is time and financially efficient. We demonstrate eight adaptations to the graphs, which consist of two suitable for full case-control study analysis, four which can be used in interim analyses to explore biases, and two which aim to improve the ease and accuracy of analyses. The adaptations are illustrated with complete, reproducible, fully-interpreted examples, including the event tree and chain event graph. Chain event graphs are used here for the first time to summarise non-participation, data collection techniques, data reliability, and disease severity in case-control studies. We demonstrate how these features of a case-control study can be incorporated into the analysis to provide further insight, which can help to identify potential biases and lead to more accurate study results.

Learning Through Chain Event Graphs: The Role of Maternal Factors in Childhood Type 1 Diabetes.

Chain event graphs (CEGs) are a graphical representation of a statistical model derived from event trees. They have previously been applied to cohort studies but not to case-control studies. In this paper, we apply the CEG framework to a Yorkshire, United Kingdom, case-control study of childhood type 1 diabetes (1993-1994) in order to examine 4 exposure variables associated with the mother, 3 of which are fully observed (her school-leaving-age, amniocenteses during pregnancy, and delivery type) and 1 with missing values (her rhesus factor), while incorporating previous type 1 diabetes knowledge. We conclude that the unknown rhesus factor values were likely to be missing not at random and were mainly rhesus-positive. The mother's school-leaving-age and rhesus factor were not associated with the diabetes status of the child, whereas having at least 1 amniocentesis procedure and, to a lesser extent, birth by cesarean delivery were associated; the combination of both procedures further increased the probability of diabetes. This application of CEGs to case-control data allows for the inclusion of missing data and prior knowledge, while investigating associations in the data. Communication of the analysis with the clinical expert is more straightforward than with traditional modeling, and this approach can be applied retrospectively or when assumptions for traditional analyses are not held.

Ankle pressures in UK South Asians with diabetes mellitus: a case control study.

OBJECTIVES: To study ethnic differences in ankle pressures in South Asians versus Europeans and in those with and without diabetes mellitus (DM). DESIGN: Case control. SETTING: Primary care. PARTICIPANTS: 391(DM=154) South Asian and 252(DM=72) European adults. INTERVENTION: None. MAIN OUTCOME MEASURES: Systolic blood pressure of the left (L) and right (R) brachial, posterior tibial (PT) and dorsalis pedis (DP) arteries were measured using a Doppler probe. RESULTS: In comparison with Europeans, in young South Asians, DM was diagnosed 12 years earlier but pressures were lower, p ≤ 0.0001 for all (RPT (146 vs 157 mm Hg), LPT (143 vs 154 mm Hg), RDP (138 vs 150 mm Hg) and LDP (137 vs 149 mm Hg)). Pack year was greater in Europeans. Odds ratios of cardiovascular disease in relation to ankle pressure were increased in South Asians with ankle brachial index between 0.9 and 1.3 or >1.3. Linear regression in South Asians identified age was an independent predictor of increased pedal pressures, DM of increased RPT and LDP, and sex of LPT and LDP. In Europeans, age was an independent predictor of increased pedal pressures, and sex and pack years were independent predictors of decreased pedal pressures. In South Asians, all ankle pressure and in Europeans, RPT, LPT and LDP were increased in subjects with DM versus without. Ankle pressures and cardiovascular disease in South Asians with DM were similar to those of 10 years older Europeans with DM. CONCLUSIONS: South Asians with DM had higher ankle pressures versus without and were similar to 10 years older Europeans with DM. Prospective studies on ankle pressures for development of diabetes or cardiovascular disease are warranted in South Asians.

Epidemiology of functional dyspepsia and subgroups in the Italian general population: an endoscopic study.

BACKGROUND & AIMS: Population-based endoscopic studies are needed to assess the epidemiology of functional dyspepsia (FD) and the newly suggested subgroups of meal-related symptoms and epigastric pain. We evaluated the prevalence of, and risk factors for, FD in the Italian general population. METHODS: A total of 1533 inhabitants of 2 villages were invited to undergo symptom evaluation using a validated questionnaire, esophagogastroduodenoscopy, and (13)C-urea breath test; 1033 subjects (67.4%) took part. RESULTS: Of the 1033 subjects, 156 (15.1%; 95% confidence interval [CI], 12.9-17.3) had dyspepsia, and of these 114 (11%; 95% CI, 9.2-12.9) had FD. Of the 114 subjects with FD, 77 (67.5%) had meal-related symptoms (postprandial fullness and/or early satiation) and 55 (48.2%) had epigastric pain. Only 18 subjects (15.8%) had both meal-related symptoms and epigastric pain; this was fewer than expected by chance alone (P < .001). Unemployment (odds ratio [OR], 5.80; 95% CI, 1.56-21.60), divorce (OR, 2.76; 95% CI, 1.10-6.91), smoking (OR, 1.74; 95% CI, 1.11-2.70), and irritable bowel syndrome (OR, 3.38; 95% CI, 1.85-6.19) were significantly associated with FD. Unemployment, divorce, and irritable bowel syndrome were associated with both meal-related symptoms and epigastric pain, while smoking was associated only with meal-related symptoms. CONCLUSIONS: FD is present in 11% of the Italian general population. Unemployment and divorce seem to increase the risk of FD, and smoking seems to be associated with meal-related symptoms. Two distinct subgroups of FD, as suggested by Rome III, seem to exist in the general population.

Dyspeptic symptoms and endoscopic findings in the community: the Loiano-Monghidoro study.

OBJECTIVES: We aimed to evaluate the prevalence of endoscopic findings and their association with dyspeptic symptoms in the community. METHODS: A total of 1,533 inhabitants of two villages were invited to participate in a cross-sectional survey, and 1,033 were recruited. Participants underwent a validated dyspepsia questionnaire, upper gastrointestinal endoscopy, and a (13)C-urea breath test. RESULTS: Endoscopic findings were present in 17.6% of asymptomatic subjects and in 27.4% of those with dyspeptic symptoms. The prevalence of esophagitis and Barrett's esophagus in subjects with dyspeptic symptoms and without prominent reflux symptoms was 8.1 and 1.5%, respectively, and was similar to that of asymptomatic subjects (8.5 and 0.7%, respectively). Esophagitis was significantly associated with dyspeptic symptoms only in subjects with concomitant prominent reflux symptoms. Peptic ulcer (PU) was present in 8.8% of subjects with dyspeptic symptoms without reflux symptoms and similarly in 9.4% of those with prominent reflux symptoms. Subjects with dyspeptic symptoms and concomitant prominent reflux symptoms had an increased risk of having an underlying PU (odds ratio 2.74, 95% confidence interval 1.30-5.78). CONCLUSIONS: Almost three-quarters of subjects with dyspeptic symptoms do not have endoscopic findings and, in addition, esophagitis may not be the cause of dyspeptic symptoms in subjects without prominent reflux symptoms. PU may be the cause of dyspeptic symptoms in a subgroup of subjects with prominent reflux symptoms.

Host, family and community proxies for infections potentially associated with leukaemia.

Three hypotheses have proposed the involvement of infections in the aetiology of childhood leukaemia, suggesting either a specific leukaemogenic infection or a series of common infections that lead to a dysregulation of the immune system. Much of the evidence for the link with infections has been based on epidemiological observations, often using proxy measures of infection. Proxy measures include population mixing, parental occupation, age distribution of incidence, spatial and space-time clustering of cases, birth order and day care during infancy. This paper discusses the proxies used and examines to what extent a commonly used proxy measure, birth order, is a fair representation of either specific infections or general infectious load. It is clear that although leukaemia, and other diseases, may be linked with infections, one needs to (1) measure specific and general infections with more accuracy and (2) understand how proxy measures relate to real infections in the population.