bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methods matter: exploring the ‘too much, too soon’ theory, part 1: causal questions in sports injury research
Authors: Nielsen Rasmus Oestergaard , Bertelsen Michael Lejbach , Møller Merete , Hulme Adam , Mansournia Mohammad Ali , Casals Marti , Parner Erik Thorlund 
Published: March 2020

BackgroundIt is widely accepted that athletes sustain sports injury if they train ‘too much, too soon’. However, not all athletes are built the same; some can tolerate more training than others. It is for this reason that prescribing the same training programme to all athletes to reduce injury risk is not optimal from a coaching perspective. Rather, athletes require individualised training plans. In acknowledgement of athlete diversity, it is therefore essential to ask the right causal research question in studies examining sports injury aetiology.PurposeIn this first part of aBritish Journal of Sports Medicineeducational series, we present four different causal research questions related to the ‘too much, too soon’ theory and critically discuss their relevance to sports injury prevention.ContentIf it is true that there is no ‘one size ﬁts all’ training programme, then we need to consider by how much training can vary depending on individual athlete characteristics. To provide an evidence-base for subgroup-specific recommendations, a stronger emphasis on the following questions is needed: (1)How much training is ‘too much’ before athletes with different characteristics sustain sports-related injury?and (2)Does the risk of sports injury differ among athletes with a certain characteristic (eg, high experience) compared with athletes with other characteristics (eg, low experience) depending on how much training they perform?ConclusionWe recommend that sports injury researchers aiming to examine the ‘too much, too soon’ theory should carefully consider how they, assisted by coaches, athletes and clinicians, pose their causal research question. In the light of the limitations of population-based prevention that intends to provide all athletes with the same advice, we argue that a stronger emphasis on research questions targeting subgroups of athletes is needed. In doing so, researchers may assist athletes, clinicians and coaches to understand what training advice/programme works best, for whom and under what circumstances.
Egg consumption and risk of cardiovascular disease: three large prospective US cohort studies, systematic review, and updated meta-analysis
Authors: Drouin-Chartier Jean-Philippe , Chen Siyu , Li Yanping , Schwab Amanda L , Stampfer Meir J , Sacks Frank M , Rosner Bernard , Willett Walter C , Hu Frank B , Bhupathiraju Shilpa N 
Published: March 2020

Abstract

Objective
To evaluate the association between egg intake and cardiovascular disease risk among women and men in the United States, and to conduct a meta-analysis of prospective cohort studies.

Design
Prospective cohort study, and a systematic review and meta-analysis of prospective cohort studies.

Setting
Nurses’ Health Study (NHS, 1980-2012), NHS II (1991-2013), Health Professionals’ Follow-Up Study (HPFS, 1986-2012).

Participants
Cohort analyses included 83 349 women from NHS, 90 214 women from NHS II, and 42 055 men from HPFS who were free of cardiovascular disease, type 2 diabetes, and cancer at baseline.

Main outcome measures
Incident cardiovascular disease, which included non-fatal myocardial infarction, fatal coronary heart disease, and stroke.

Results

Over up to 32 years of follow-up (>5.54 million person years), 14 806 participants with incident cardiovascular disease were identified in the three cohorts. Participants with a higher egg intake had a higher body mass index, were less likely to be treated with statins, and consumed more red meats. Most people consumed between one and less than five eggs per week. In the pooled multivariable analysis, consumption of at least one egg per day was not associated with incident cardiovascular disease risk after adjustment for updated lifestyle and dietary factors associated with egg intake (hazard ratio for at least one egg per day
v
less than one egg per month 0.93, 95% confidence interval 0.82 to 1.05). In the updated meta-analysis of prospective cohort studies (33 risk estimates, 1 720 108 participants, 139 195 cardiovascular disease events), an increase of one egg per day was not associated with cardiovascular disease risk (pooled relative risk 0.98, 95% confidence interval 0.93 to 1.03, I
2
=62.3%). Results were similar for coronary heart disease (21 risk estimates, 1 411 261 participants, 59 713 coronary heart disease events; 0.96, 0.91 to 1.03, I
2
=38.2%), and stroke (22 risk estimates, 1 059 315 participants, 53 617 stroke events; 0.99, 0.91 to 1.07, I
2
=71.5%). In analyses stratified by geographical location (P for interaction=0.07), no association was found between egg consumption and cardiovascular disease risk among US cohorts (1.01, 0.96 to 1.06, I
2
=30.8%) or European cohorts (1.05, 0.92 to 1.19, I
2
=64.7%), but an inverse association was seen in Asian cohorts (0.92, 0.85 to 0.99, I
2
=44.8%).

Conclusions
Results from the three cohorts and from the updated meta-analysis show that moderate egg consumption (up to one egg per day) is not associated with cardiovascular disease risk overall, and is associated with potentially lower cardiovascular disease risk in Asian populations.

Systematic review registration
PROSPERO CRD42019129650.
Combined and sequential non-invasive approach to diagnosing non-alcoholic steatohepatitis in patients with non-alcoholic fatty liver disease and persistently normal alanine aminotransferase levels
Authors: Zheng Kenneth I , Liu Wen-Yue , Pan Xiao-Yan , Ma Hong-Lei , Zhu Pei-Wu , Wu Xi-Xi , Targher Giovanni , Byrne Christopher , Wang Xiao-Dong , Chen Yong-Ping , Lu Fengmin , Zheng Ming-Hua 
Published: March 2020

Background and aimImaging-confirmed non-alcoholic fatty liver disease (NAFLD) with normal alanine aminotransferase (nALT) levels is infrequently the subject for further evaluation. Early diagnosis of non-alcoholic steatohepatitis (NASH) is needed to prevent disease progression. Thus, we tested the clinical utility of serum Golgi protein 73 (GP73) levels and developed a new non-invasive score to diagnose NASH in patients with biopsy-confirmed NAFLD and persistent nALT levels.MethodsSerum GP73 and cytokeratin-18 M30 fragments (CK18-M30) levels were measured in 345 patients with biopsy-proven NAFLD. We developed a new score, named G-NASH model (by incorporating serum GP73), and combined it with serum CK18-M30 measurement in a sequential non-invasive approach to accurately identify NASH among patients with NAFLD and persistent nALT levels.Results105 (30.4%) patients had persistent nALT, 53 of whom had histologically confirmed NASH. Both serum GP73 and CK18-M30 levels alone had poor diagnostic accuracy in identifying NASH (55.2% and 51.6%, respectively) in these patients. Conversely, G-NASH model performed better than other established non-invasive scoring systems, and by using our proposed sequential non-invasive approach 82.9% of patients with NASH were correctly identified.ConclusionsNASH is highly prevalent in patients with NAFLD with persistent nALT levels. The G-NASH model accurately identifies NASH in this patient group.
Challenges in meta-analyses with observational studies
Authors: Metelli Silvia , Chaimani Anna 
Published: March 2020

ObjectiveMeta-analyses of observational studies are frequently published in the literature, but they are generally considered suboptimal to those involving randomised controlled trials (RCTs) only. This is due to the increased risk of biases that observational studies may entail as well as because of the high heterogeneity that might be present. In this article, we highlight aspects of meta-analyses with observational studies that need more careful consideration in comparison to meta-analyses of RCTs.MethodsWe present an overview of recommendations from the literature with respect to how the different steps of a meta-analysis involving observational studies should be comprehensively conducted. We focus more on issues arising at the step of the quantitative synthesis, in terms of handling heterogeneity and biases. We briefly describe some sophisticated synthesis methods, which may allow for more flexible modelling approaches than common meta-analysis models. We illustrate the issues encountered in the presence of observational studies using an example from mental health, which assesses the risk of myocardial infarction in antipsychotic drug users.ResultsThe increased heterogeneity observed among studies challenges the interpretation of the diamond, while the inclusion of short exposure studies may lead to an exaggerated risk for myocardial infarction in this population.ConclusionsIn the presence of observational study designs, prior to synthesis, investigators should carefully consider whether all studies at hand are able to answer the same clinical question. The potential for a quantitative synthesis should be guided through examination of the amount of clinical and methodological heterogeneity and assessment of possible biases.
Successful endotracheal intubation following a failed first attempt during aeromedical retrieval
Authors: Glasheen John , Hooper Jeff , Donohue Andrew , Finn Emmeline , Murray-Smith Bronwyn , Bolot Renée , Edwards Mark 
Published: March 2020

IntroductionFirst attempt intubation success is used by many prehospital services as a marker of quality and safety. An increasing complication rate is associated with repeated intubation attempts. The aim of this study was to identify changes to intubation technique following a failed intubation attempt.MethodsLifeFlight Retrieval Medicine provides aeromedical retrieval services in Queensland, Australia. This retrospective study identified cases of failed intubation attempts from an electronic database registry over a 41-month period from March 2015 to July 2018. These data were analysed using descriptive statistics.ResultsOf the 762 patients who required intubation 758 (99.5%) were successfully intubated, with 684 intubated at the first attempt (89.8%; 95% CI: 0.87 to 0.92). There was no difference in first attempt success between direct and video laryngoscopy (511/563 (90.8%) vs 172/194 (88.6%) p=0.38), trauma or medical (374/419 (89.3%) vs 310/343 (90.4%), p=0.61), primary or interhospital missions (329/370 (88.7%) vs 355/392 (90.8%), p=0.33). 78 cases of failed first attempt intubations were identified. In 65 of these cases, intubation was successful at the second attempt. A single change was made to the intubation procedure prior to a second successful attempt in 28/78 cases (35.9%), and more than one change was made in 41/78 (52.6%). The changes included the operator, intubation device, patient position, intubating aid and external laryngeal manipulation. No change between attempts was recorded in 9/78 (11.5%). 9 cases were successfully intubated at the third attempt, and changes prior to the third attempt included operator, device and intubating aid.ConclusionAlthough a high overall intubation success was found, one in ten patients who were intubated had a failed first attempt. The majority of successful subsequent attempts were preceded by at least one change to intubating technique. Intubating clinicians need the ability to identify and correct issues leading to a failed first attempt.
Early versus delayed emergency department presentation following mild Traumatic Brain Injury and the presence of symptom at 1, 4 and 12 weeks in children
Authors: Gravel Jocelyn , Ledoux Andrée-Ann , Tang Ken , Yeates Keith Owens , Craig William , Osmond Martin , Boutis Kathy , Burns Emma , Sangha Gurinder , Dubrovsky Alexander Sasha , Beer Darcy , Zemek Roger 
Published: March 2020

ObjectivesWe evaluated the association between timing of presentation and postconcussive symptoms (PCS) at 1, 4 and 12 weeks after injury.MethodsThis was a secondary analysis of a prospective cohort study conducted in nine Canadian paediatric EDs in 2013–2015 (5P study). Participants were children who suffered a head injury within the preceding 48 hours and met Zurich consensus concussion diagnostic criteria. The exposure was the time between head injury and ED presentation. The primary outcome was the presence of PCS at 1 week defined by the presence of at least three symptoms on the Post-Concussion Symptom Inventory (PCSI). Secondary outcomes evaluated PCS at 4 and 12 weeks. Multivariable logistic regression analyses were adjusted for ED PCSI and other potential confounders.ResultsThere were 3041 patients with a concussion in which timing of the injury was known. 2287 (75%) participants sought care in the first 12 hours, 388 (13%) 12–24 hours after trauma and 366 (12%) between 24 and 48 hours. Compared with children who sought care >24 hours after trauma, children who sought care in the first 12 hours had a significantly lower incidence of PCS at 1 week (OR: 0.55 (95% CI 0.41 to 0.75)) and 4 weeks (OR: 0.74 (95% CI 0.56 to 0.99)) but not at 12 weeks (OR: 0.88 (95% CI 0.63 to 1.23)).ConclusionsPatients who present early after a concussion appear to have a shorter duration of PCS than those presenting more than 12 hours later. Patients/families should be informed of the higher probability of PCS in children with delayed presentation.
Substantial and sustained improvement of serrated polyp detection after a simple educational intervention: results from a prospective controlled trial
Authors: Bleijenberg Arne G C , van Leerdam Monique E , Bargeman Marloes , Koornstra Jan Jacob , van Herwaarden Yasmijn J , Spaander Manon CW , Sanduleanu Silvia , Bastiaansen Barbara A J , Schoon Erik J , van Lelyveld Niels , Dekker Evelien , IJspeert Joep E G 
Published: March 2020

ObjectiveSerrated polyps (SPs) are an important cause of postcolonoscopy colorectal cancers (PCCRCs), which is likely the result of suboptimal SP detection during colonoscopy. We assessed the long-term effect of a simple educational intervention focusing on optimising SP detection.DesignAn educational intervention, consisting of two 45 min training sessions (held 3 years apart) on serrated polyp detection, was given to endoscopists from 9 Dutch hospitals. Hundred randomly selected and untrained endoscopists from other hospitals were selected as control group. Our primary outcome measure was the proximal SP detection rate (PSPDR) in trained versus untrained endoscopists who participated in our faecal immunochemical test (FIT)-based population screening programme.ResultsSeventeen trained and 100 untrained endoscopists were included, who performed 11 305 and 51 039 colonoscopies, respectively. At baseline, PSPDR was equal between the groups (9.3% vs 9.3%). After training, the PSPDR of trained endoscopists gradually increased to 15.6% in 2018. This was significantly higher than the PSPDR of untrained endoscopists, which remained stable around 10% (p=0.018). All below-average (ie, PSPDR ≤6%) endoscopists at baseline improved their PSPDR after training session 1, as did 57% of endoscopists with average PSPDR (6%–12%) at baseline. The second training session further improved the PSPDR in 44% of endoscopists with average PSPDR after the first training.ConclusionA simple educational intervention was associated with substantial long-term improvement of PSPDR in a prospective controlled trial within FIT-based population screening. Widespread implementation of such interventions might be an easy way to improve SP detection, which may ultimately result in fewer PCCRCs.Trial registration numberNCT03902899.
Veterinary care of guinea pigs
Authors: Rowland Mark 
Published: March 2020

Background: Guinea pigs have become very popular in the pet trade and have been extensively bred for colour and coat mutations. They should not be considered as just a children's pet, as many guinea pigs presented to vets are kept by adults who have the same veterinary expectations for these animals as they would have for dogs and cats. Therefore, it is very important that vets have a working knowledge of guinea pig anatomy and physiology in order to expedite an appropriate diagnostic and therapeutic plan. This is especially true of guinea pigs as they are capable of sudden rapid deterioration in their clinical condition. As with all exotics, the provision of supportive care forms a cornerstone in their rehabilitation.Aim of the article: This article provides a guide to dealing with guinea pigs and an overview of the common conditions they present with.
Women in academic medicine leadership: correlation between sex of medical school deans and affiliated academic hospital system CEOs
Authors: Marshall Ariela L , Durani Urshila , Mikhael Joseph 
Published: March 2020

BackgroundWomen are currently under-represented in ‘C-suite’ leadership positions at academic medical centres, including medical school deans, department chairs and hospital chief executive officers (CEOs). There are many potential reasons for the low percentage of women in academic medical leadership, including lack of mentorship and sponsorship, increased non-work responsibilities compared with men, implicit bias, and others.MethodsWe collected data from 136 fully accredited US allopathic medical schools regarding sex of the medical school dean and sex of the CEO of the largest academic medical centre/teaching hospital affiliate. Schools where students rotate at non-academic centres were excluded from the final analysis, leaving 124 schools where we investigated the relationship between sex of US medical school dean and affiliated academic medical centre CEO.Results16.9% of current medical school deans and 17.7% of affiliated academic medical centre CEOs were female. Systems with one female leader were significantly (6.25-fold, 95% CI 2.22 to 17.56, p=0.001) more likely to have a second female leader, regardless of geographical region or institution type (public vs private).ConclusionsThere is a significant positive association between medical school dean and affiliated academic hospital centre CEO sex. There are many potential factors that could contribute to this positive association, including mentorship, sponsorship and medical system consciousness about gender equity, among others. This relationship is important to recognise as we strive for more gender parity for women in positions of leadership in academic medicine.
Assessment of exercise-induced changes in von Willebrand factor as a marker of severity of aortic stenosis
Authors: Zelis Jo M , Zimmermann Frederik M , Andriessen Froukje P J , Houthuizen Patrick , Van de Ven Jop , Leuverman Jolanda , Johnson Nils P , Pijls Nico H J , Scharnhorst Volkher , Van 't Veer Marcel , Tonino Pim A L 
Published: March 2020

BackgroundLoss of high-molecular-weight multimers (HMWMs) of von Willebrand factor (vWF) occurs due to high shear stress in patients with aortic stenosis. As symptoms of aortic stenosis occur during exercise, measurement of vWF during exercise might identify patients with aortic stenosis of clinical importance. The aim of this pilot study is to evaluate whether vWF changes over time as a result of exercise in patients with asymptomatic moderate or severe aortic stenosis.MethodsTen subjects were analysed for changes in vWF by measuring HMWMs and closure time with adenosine diphosphate (CT-ADP). All subjects underwent a full stress test on a bicycle ergometer. At rest and at peak exercise, a transthoracic echocardiogram was performed. HMWMs and CT-ADP were assessed at baseline, during and after exercise.ResultsHMWMs and CT-ADP did not change significantly during exercise, p=0.45 and p=0.65, respectively. HMWMs and CT-ADP correlated well, Spearman’s rho −0.621, p<0.001. HMWMs during peak exercise did not correlate with maximal velocity measured, p=0.21. CT-ADP during exercise correlated well with the maximal echocardiographic velocity over the aortic valve (AV), rho 0.82, p=0.04.ConclusionsIn a cohort of 10 patients with moderate or severe aortic stenosis, we observed no significant change in vWF biomarkers during exercise. Peak CT-ADP during exercise showed a good correlation with peak AV velocity measured with echo. Although CT-ADP is an easy test to perform and could be an alternative for peak AV velocity measured during exercise, our results suggest that it can only detect large changes in shear stress.
External validation of a convolutional neural network artificial intelligence tool to predict malignancy in pulmonary nodules
Authors: Baldwin David R , Gustafson Jennifer , Pickup Lyndsey , Arteta Carlos , Novotny Petr , Declerck Jerome , Kadir Timor , Figueiras Catarina , Sterba Albert , Exell Alan , Potesil Vaclav , Holland Paul , Spence Hazel , Clubley Alison , O'Dowd Emma , Clark Matthew , Ashford-Turner Victoria , Callister Matthew EJ , Gleeson Fergus V 
Published: March 2020

BackgroundEstimation of the risk of malignancy in pulmonary nodules detected by CT is central in clinical management. The use of artificial intelligence (AI) offers an opportunity to improve risk prediction. Here we compare the performance of an AI algorithm, the lung cancer prediction convolutional neural network (LCP-CNN), with that of the Brock University model, recommended in UK guidelines.MethodsA dataset of incidentally detected pulmonary nodules measuring 5–15 mm was collected retrospectively from three UK hospitals for use in a validation study. Ground truth diagnosis for each nodule was based on histology (required for any cancer), resolution, stability or (for pulmonary lymph nodes only) expert opinion. There were 1397 nodules in 1187 patients, of which 234 nodules in 229 (19.3%) patients were cancer. Model discrimination and performance statistics at predefined score thresholds were compared between the Brock model and the LCP-CNN.ResultsThe area under the curve for LCP-CNN was 89.6% (95% CI 87.6 to 91.5), compared with 86.8% (95% CI 84.3 to 89.1) for the Brock model (p≤0.005). Using the LCP-CNN, we found that 24.5% of nodules scored below the lowest cancer nodule score, compared with 10.9% using the Brock score. Using the predefined thresholds, we found that the LCP-CNN gave one false negative (0.4% of cancers), whereas the Brock model gave six (2.5%), while specificity statistics were similar between the two models.ConclusionThe LCP-CNN score has better discrimination and allows a larger proportion of benign nodules to be identified without missing cancers than the Brock model. This has the potential to substantially reduce the proportion of surveillance CT scans required and thus save significant resources.