Using signal detection theory to model changes in serial learning of radiological image interpretation

Signal detection theory (SDT) parameters can describe a learner's ability to discriminate (d') normal from abnormal and the learner's criterion (λ) to under or overcall abnormalities. To examine the serial changes in SDT parameters with serial exposure to radiological cases. 46 participants were recruited for this study: 20 medical students (MED), 6 residents (RES), 12 fellows (FEL), 5 staff pediatric emergency physicians (PEM), and 3 staff radiologists (RAD). Each participant was presented with 234 randomly assigned ankle radiographs using a web-based application. Participants were given a clinical scenario and considered 3 views of the ankle. They classified each case as normal or abnormal. For abnormal cases, they specified the location of the abnormality. Immediate feedback included highlighting on the images and the official radiologist's report. The low experience group (MED, RES, FEL) showed steady improvement in discrimination ability with each case, while the high experience group (PEM, RAD) had higher and stable discrimination ability throughout the exercise. There was also a difference in the way the high and low experience groups balanced sensitivity and specificity (λ) with the low experience group tending to make more errors calling positive radiographs negative. This tendency was progressively less evident with each increase in expertise level. SDT metrics provide valuable insight on changes associated with learning radiograph interpretation, and may be used to design more effective instructional strategies for a given learner group

Interpretation difficulty of normal versus abnormal radiographs using a pediatric example

Background: Radiograph teaching files are usually dominated by abnormal cases, implying that normal radiographs are easier to interpret. Our main objective was to compare the interpretation difficulty of normal versus abnormal radiographs of a set of common pediatric radiographs.Methods: We developed a 234-item digital case bank of pediatric ankle radiographs, recruited a convenience sample of participants, and presented the cases to each participant who then classified the cases as normal or abnormal. We determined and contrasted the interpretation difficulty of the normal and abnormal x-rays items using Rasch Measurement Theory. We also identified case features that were associated with item difficulty.Results: 139 participants (86 medical students, 7 residents, 29 fellows, 5 emergency physicians, and 3 radiologists) rated a minimum of 50 cases each, which resulted in 16,535 total ratings. Abnormal cases were more difficult (+0.99 logits) than were normal ones (-0.58 logits), difference 1.57 logits (95% CI 1.2, 2.0), but there was considerable overlap in difficulty scores. Patient variables associated with a more difficult normal radiograph included younger patient age (β = -0.16, 95% CI -0.22, -0.10), history of distal fibular tenderness (β = 0.55, 95% CI 0.17, 0.93), and presence of a secondary ossification centre (β = 0.84, 95% CI 0.27, 1.41).Conclusions: While abnormal images were more difficult to interpret, normal images did show a range of interpretation difficulties. Including a significant proportion of normal cases may be of benefit to learners

Interleukin-8 predicts fatigue at 12 months post-injury in children with traumatic brain injury

Despite many children experiencing fatigue after childhood brain injury, little is known about the predictors of this complaint. To date, traditional indices of traumatic brain injury (TBI) severity have not reliably predicted persisting fatigue (up to 3 years post‐injury). This study aimed to establish if persisting fatigue is predicted by serum biomarker concentrations in child TBI. We examined if acute serum biomarker expression would improve prediction models of 12‐month fatigue based on injury severity. Blood samples were collected from 87 children (1 – 17 years at injury) sustaining mild to severe TBI (GCS range 3‐15; mean 12.43; classified as mild TBI (n=50, 57%) vs moderate/severe TBI n=37, 43%), and presenting to the Emergency Departments (ED) and Pediatric Intensive Care Units (PICU) at one of three tertiary pediatric hospitals (Royal Children’s Hospital (RCH); Hospital for Sick Children (HSC), Toronto St Justine Children’s Hospital (SJH), Montreal). Six serum biomarker concentrations were measured within 24 hours of injury [interleukin‐6 (IL‐6), interleukin‐8 (IL‐8), soluble vascular cell adhesion molecule (SVCAM), S100 calcium binding protein B (S100B), neuron specific enolase (NSE), and soluble neural cell adhesion molecule (sNCAM)]. Fatigue at 12 months post‐injury was measured using the Pediatric Quality of Life Inventory Multidimensional Fatigue Scale (parent report), classified as present/absent using previously derived cut‐points. At 12 months post‐injury, 22% of participants experienced fatigue. A model including interleukin‐8 (IL‐8) was the best serum biomarker for estimating the probability of children experiencing fatigue at 12 months post‐injury. IL‐8 also significantly improved predictive models of fatigue based on severity

Clinical risk score for persistent postconcussion symptomsamong children with acute concussion in the ED

IMPORTANCE Approximately one-third of children experiencing acute concussion experience ongoing somatic, cognitive, and psychological or behavioral symptoms, referred to as persistent postconcussion symptoms (PPCS). However, validated and pragmatic tools enabling clinicians to identify patients at risk for PPCS do not exist. OBJECTIVE To derive and validate a clinical risk score for PPCS among children presenting to the emergency department. DESIGN, SETTING, AND PARTICIPANTS Prospective, multicenter cohort study (Predicting and Preventing Postconcussive Problems in Pediatrics [5P]) enrolled young patients (aged 5-\u3c18 years) who presented within 48 hours of an acute head injury at 1 of 9 pediatric emergency departments within the Pediatric Emergency Research Canada (PERC) network from August 2013 through September 2014 (derivation cohort) and from October 2014 through June 2015 (validation cohort). Participants completed follow-up 28 days after the injury. EXPOSURES All eligible patients had concussions consistent with the Zurich consensus diagnostic criteria. MAIN OUTCOMES AND MEASURES The primary outcomewas PPCS risk score at 28 days, which was defined as 3 or more new or worsening symptoms using the patient-reported Postconcussion Symptom Inventory compared with recalled state of being prior to the injury. RESULTS In total, 3063 patients (median age, 12.0 years [interquartile range, 9.2-14.6 years]; 1205 [39.3%] girls) were enrolled (n = 2006 in the derivation cohort; n = 1057 in the validation cohort) and 2584 of whom (n = 1701 [85%] in the derivation cohort; n = 883 [84%] in the validation cohort) completed follow-up at 28 days after the injury. Persistent postconcussion symptoms were present in 801 patients (31.0%) (n = 510 [30.0%] in the derivation cohort and n = 291 [33.0%] in the validation cohort). The 12-point PPCS risk score model for the derivation cohort included the variables of female sex, age of 13 years or older, physician-diagnosed migraine history, prior concussion with symptoms lasting longer than 1 week, headache, sensitivity to noise, fatigue, answering questions slowly, and 4 or more errors on the Balance Error Scoring System tandem stance. The area under the curve was 0.71 (95%CI, 0.69-0.74) for the derivation cohort and 0.68 (95%CI, 0.65-0.72) for the validation cohort. CONCLUSIONS AND RELEVANCE A clinical risk score developed among children presenting to the emergency department with concussion and head injury within the previous 48 hours had modest discrimination to stratify PPCS risk at 28 days. Before this score is adopted in clinical practice, further research is needed for external validation, assessment of accuracy in an office setting, and determination of clinical utility

Persistent ventilation inhomogeneity after an acute exacerbation in preschool children with recurrent wheezing

© 2020 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd. Background: Preschool children with recurrent wheezing suffer high morbidity. It is unclear whether objective measures of asthma control, such as pulmonary function tests (PFTs), provide additional information to the clinical assessment. Methods: We recruited children between 3 and 6years old, with a history of recurrent wheezing in the preceding year and treated for acute wheezing exacerbation in the emergency department (ED) into an observational cohort study. Children attended two outpatient visits: the first study visit within five days of discharge from the ED and the second study visit 12weeks after the ED visit. We performed standardized symptom score (test for respiratory and asthma control in kids (TRACK)), multiple breath washout (MBW), spirometry, and clinical assessment at both visits. Results: Seventy-four children, mean (standard deviation (SD)) age of 4.32years (0.84), attended both visits. Paired FEV0.75 and lung clearance index (LCI) measurements at both time points were obtained in 37 and 34 subjects, respectively. Feasibility for all tests improved at visit 2 and was not age-dependent. At the second study visit, a third had controlled asthma based on the TRACK score, and the mean lung clearance index (LCI) improved from 9.86 to 8.31 (P=.003); however, 46% had an LCI in the abnormal range. FEV0.75 z-score improved from −1.66 to −1.17 (P=.05) but remained in the abnormal range in 24%. LCI was abnormal in more than half of the children with “well-controlled” asthma based on the TRACK score. There was no correlation between PFT measures and TRACK scores at either visit. Conclusions: Lung clearance index demonstrates a persistent deficit post-exacerbation in a large proportion of preschoolers with recurrent wheezing, highlighting that symptom scores alone may not suffice for monitoring these children

Twelve Tips for using Learning Curves in Health Professions Education Research [version 1; peer review: 3 approved]

Learning curves can be used to design, implement, and evaluate educational interventions. Attention to key aspects of the method can improve the fidelity of this representation of learning as well as its suitability for education and research purposes. This paper addresses when to use a learning curve, which graphical properties to consider, how to use learning curves quantitatively, and how to use observed thresholds to communicate meaning. We also address the associated ethics and policy considerations. We conclude with a best practices checklist for both educators and researchers seeking to use learning curves in their work

Computed Tomography Risk Disclosure in the Emergency Department: A Survey of Pediatric Emergency Medicine Fellowship Program Leaders

Introduction: Given the potential malignancy risks associated with computed tomography (CT), some physicians are increasingly advocating for risk disclosure to patients/families.Objective: Our goal was to evaluate the practices and attitudes of pediatric emergency medicine (PEM) fellowship program leaders’ regarding CT radiation-risk disclosure.Methods: We conducted a cross-sectional survey study of U.S. and Canadian PEM fellowship directors and associate/assistant directors. We developed a web-based survey using a modified Dillman technique. Primary outcome was the proportion who “almost always” or “most of the time” discussed potential malignancy risks from CT prior to ordering this test.Results: Of 128 physicians who received the survey, 108 (86%) responded. Of those respondents, 73%, 95% confidence interval (CI) [64-81] reported “almost always” or “most of the time” discussing potential malignancy risks when ordering a CT for infants; proportions for toddlers, school-age children, and teenagers were 72% (95% CI [63-80]), 66% (95% CI [56-75]), and 58% (95% CI [48-67]), respectively (test for trend, p=0.008). Eighty percent reported being “extremely” or “very” comfortable discussing radiation risks. Factors of “high” or “very high” importance in disclosing risks included parent request for a CT not deemed clinically indicated for 94% of respondents, and parent-initiated queries about radiation risks for 79%. If risk disclosure became mandatory, 82% favored verbal discussion over written informed consent.Conclusion: PEM fellowship program leaders report frequently disclosing potential malignancy risks from CT, with the frequency varying inversely with patient age. Motivating factors for discussions included parental request for a CT deemed clinically unnecessary and parental inquiry about risks