Publications (11)59.26 Total impact
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Article: Steroids and bronchodilators for acute bronchiolitis in the first two years of life: systematic review and meta-analysis.
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ABSTRACT: To evaluate and compare the efficacy and safety of bronchodilators and steroids, alone or combined, for the acute management of bronchiolitis in children aged less than 2 years. Systematic review and meta-analysis. Medline, Embase, Central, Scopus, PubMed, LILACS, IranMedEx, conference proceedings, and trial registers. Inclusion criteria Randomised controlled trials of children aged 24 months or less with a first episode of bronchiolitis with wheezing comparing any bronchodilator or steroid, alone or combined, with placebo or another intervention (other bronchodilator, other steroid, standard care). Two reviewers assessed studies for inclusion and risk of bias and extracted data. Primary outcomes were selected by clinicians a priori based on clinical relevance: rate of admission for outpatients (day 1 and up to day 7) and length of stay for inpatients. Direct meta-analyses were carried out using random effects models. A mixed treatment comparison using a Bayesian network model was used to compare all interventions simultaneously. 48 trials (4897 patients, 13 comparisons) were included. Risk of bias was low in 17% (n = 8), unclear in 52% (n = 25), and high in 31% (n = 15). Only adrenaline (epinephrine) reduced admissions on day 1 (compared with placebo: pooled risk ratio 0.67, 95% confidence interval 0.50 to 0.89; number needed to treat 15, 95% confidence interval 10 to 45 for a baseline risk of 20%; 920 patients). Unadjusted results from a single large trial with low risk of bias showed that combined dexamethasone and adrenaline reduced admissions on day 7 (risk ratio 0.65, 0.44 to 0.95; number needed to treat 11, 7 to 76 for a baseline risk of 26%; 400 patients). A mixed treatment comparison supported adrenaline alone or combined with steroids as the preferred treatments for outpatients (probability of being the best treatment based on admissions at day 1 were 45% and 39%, respectively). The incidence of reported harms did not differ. None of the interventions examined showed clear efficacy for length of stay among inpatients. Evidence shows the effectiveness and superiority of adrenaline for outcomes of most clinical relevance among outpatients with acute bronchiolitis, and evidence from a single precise trial for combined adrenaline and dexamethasone.BMJ 01/2011; 342:d1714. · 14.09 Impact Factor -
Article: Pediatric emergency research networks: a global initiative in pediatric emergency medicine.
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ABSTRACT: Objectives of the Pediatric Emergency Research Network's (PERN's) meeting included (1) learn about each of the participating network's missions, goals, and infrastructure; (2) share important contributions each network has made to the creation of new knowledge; (3) discuss "best practices" to improve each network's effectiveness; and (4) explore the potential for a collaborative research project as proof of concept that would help us promote quality of care of the acutely ill and injured child/youth globally. In October 2009, a multiday meeting was attended by 18 delegates representing the following pediatric emergency medicine research networks: Pediatric Emergency Medicine Collaborative Research Committee (United States), Pediatric Emergency Care Applied Research Network (United States), Pediatric Emergency Research of Canada (Canada), Paediatric Research in Emergency Departments International Collaborative (Australia and New Zealand), and Research in European Pediatric Emergency Medicine (15 countries in Europe and the Middle East). The inaugural meeting of PERN demonstrated that there is a common desire for high-quality research and the dissemination of this research to improve health and outcomes of acutely ill and injured children and youths throughout the world. Presently, the PERN group is in the final stages of developing a protocol to assess H1N1 risk factors with the collection of retrospective data. Several members of PERN will be gathering at the International Conference on Emergency Medicine in Singapore, where the group will be presenting information about the H1N1 initiative. The PERN group is planning to bring together all 5 networks later in 2010 to discuss future global collaborations.Pediatric emergency care 08/2010; 26(8):541-3. · 0.92 Impact Factor -
Article: A systematic review on the diagnosis of pediatric bacterial pneumonia: when gold is bronze.
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ABSTRACT: In developing countries, pneumonia is one of the leading causes of death in children under five years of age and hence timely and accurate diagnosis is critical. In North America, pneumonia is also a common source of childhood morbidity and occasionally mortality. Clinicians traditionally have used the chest radiograph as the gold standard in the diagnosis of pneumonia, but they are becoming increasingly aware that it is not ideal. Numerous studies have shown that chest radiography findings lack precision in defining the etiology of childhood pneumonia. There is no single test that reliably distinguishes bacterial from non-bacterial causes. These factors have resulted in clinicians historically using a combination of physical signs and chest radiographs as a 'gold standard', though this combination of tests has been shown to be imperfect for diagnosis and assigning treatment. The objectives of this systematic review are to: 1) identify and categorize studies that have used single or multiple tests as a gold standard for assessing accuracy of other tests, and 2) given the 'gold standard' used, determine the accuracy of these other tests for diagnosing childhood bacterial pneumonia. Search strategies were developed using a combination of subject headings and keywords adapted for 18 electronic bibliographic databases from inception to May 2008. Published studies were included if they: 1) included children one month to 18 years of age, 2) provided sufficient data regarding diagnostic accuracy to construct a 2x2 table, and 3) assessed the accuracy of one or more index tests as compared with other test(s) used as a 'gold standard'. The literature search revealed 5,989 references of which 256 were screened for inclusion, resulting in 25 studies that satisfied all inclusion criteria. The studies examined a range of bacterium types and assessed the accuracy of several combinations of diagnostic tests. Eleven different gold standards were studied in the 25 included studies. Criterion validity was calculated for fourteen different index tests using eleven different gold standards. The most common gold standard utilized was blood culture tests used in six studies. Fourteen different tests were measured as index tests. PCT was the most common measured in five studies each with a different gold standard. We have found that studies assessing the diagnostic accuracy of clinical, radiological, and laboratory tests for bacterial childhood pneumonia have used a heterogeneous group of gold standards, and found, at least in part because of this, that index tests have widely different accuracies. These findings highlight the need for identifying a widely accepted gold standard for diagnosis of bacterial pneumonia in children.PLoS ONE 01/2010; 5(8):e11989. · 4.09 Impact Factor -
Article: Exercise-induced bronchoconstriction and asthma.
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ABSTRACT: The objectives are: (1) To assess diagnostic test characteristics of six alternative index tests compared with the selected reference standard-a standardized exercise challenge test (ECT) in patients with suspected exercise-induced bronchoconstriction or asthma (EIB/EIA); (2) to determine the efficacy of a single prophylactic dose of four pharmacologic and one nonpharmacologic interventions vs. placebo to attenuate EIB/EIA in patients with diagnosed EIB/EIA; and (3) to determine if regular daily treatment with short-acting or long-acting beta-agonists (SABA or LABA) causes patients with EIA to develop tachyphylaxis when additional prophylactic doses are used pre-exercise. A systematic and comprehensive literature search was conducted in 14 electronic databases (Diagnosis) and the Cochrane Airways Register (Therapy). Study selection, quality assessment, and data extraction were conducted independently by two reviewers. The primary outcome was the maximum percent fall in the post-exercise forced expiratory volume in 1 second (percent fall FEV1). The diagnostic threshold for a positive ECT was a percent fall FEV1 of 10% or more. Sensitivity (SN) and specificity (SP) were calculated. For therapy, mean differences (MD) in the percent fall FEV1 and 95% confidence intervals (CI) (random effects model) were calculated. A positive MD indicates the intervention works better than the control. For the diagnostic reviews, 5,318 citations yielded 28 relevant studies; for the therapy reviews, 1,634 citations yielded 109 relevant RCTs. Diagnostic test results versus ECT: self-reported history (2 studies) SN=36-8 percent; SP=85-86 percent; sport specific challenges (5 studies) SN=0-100 percent, SP=0-100 percent; eucapnic voluntary hyperpnea (7 studies) SN=25-90 percent, SP=0-71 percent; free running asthma screening test (3 studies) SN=60-67 percent, SP=47-67 percent; mannitol (3 studies) SN=58-96 percent, SP=65-78 percent. All SN and SP calculations indicated substantial heterogeneity that could not be explained by sensitivity or subgroup analyses. Therapy results: SABA offered greater protection than mast cell stabilizers (MCS) (12 studies); MD=6.8 (95 percent CI: 4.5, 9.2) but combining them offered no additional benefit; SABA versus MCS plus SABA (5 studies) MD=1.3 (95 percent CI: -6.3, 8.9). Leukotriene receptor antagonists (LTRA), MCS, ipratropium bromide, and interval warmup routines provided statistically significant attenuation of EIA when compared with placebo; inhaled corticosteroids (ICS) and other warmup routines did not. Single-dose intervention versus placebo results are: LTRA (9 studies) MD=8.9 (95 percent CI: 6.9, 11.0); MCS (nedocromil sodium) (17 studies) MD=15.6 (95 percent CI: 13.2, 18.2); interval warmup versus no warmup (4 studies) MD=10.6 (95 percent CI: 6.5, 14.7); ICS (4 studies) MD=5.0 (95 percent CI: 0.0, 9.9); continuous low intensity warmup versus no warmup (3 studies) MD=12.6 (95 percent CI: -1.5, 26.7); continuous high intensity warmup versus no warmup (2 studies) MD=9.8 (95 percent CI: -6.4, 26.0). After daily LABA (salmeterol) use for 3 to 4 weeks (4 studies), the percent fall FEV1 following an ECT at 2 and 4 weeks was greater than at day 1 in the LABA arm indicating that tachyphylaxis to prophylactic LABA use occurred. Daily SABA use for 1 week (1 study) also indicated development of tachyphylaxis. However, both LABA and SABA continued to have an attenuating effect on EIA. Given the small number of studies comparing EIB/EIA diagnostic tests, the heterogeneity of the study populations, and the varied study methodologies, there is no clear evidence that any of the index tests are a suitable replacement for a standardized ECT to diagnose EIB/EIA in the general population. All bronchodilator agents and most anti-inflammatory agents when used as pretreatment are somewhat effective in attenuating the percent fall FEV1 associated with EIA.Evidence report/technology assessment 01/2010; -
Article: Improving outcomes for ill and injured children in emergency departments: protocol for a program in pediatric emergency medicine and knowledge translation science.
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ABSTRACT: Approximately one-quarter of all Canadian children will seek emergency care in any given year, with the two most common medical problems affecting children in the emergency department (ED) being acute respiratory illness and injury. Treatment for some medical conditions in the ED remains controversial due to a lack of strong supporting evidence. The purpose of this paper is to describe a multi-centre team grant in pediatric emergency medicine (PEM) that has been recently funded by the Canadian Institutes of Health Research (CIHR). This program of research integrates clinical research (in the areas of acute respiratory illness and injury) and knowledge translation (KT). This initiative includes seven distinct projects that address the objective to generate new evidence for clinical care and KT in the pediatric ED. Five of the seven research projects in this team grant make significant contributions to knowledge development in KT science, and these contributions are the focus of this paper. The research designs employed in this program include: cross-sectional surveys, randomized controlled trials (RCTs), quasi-experimental designs with interrupted time-series analysis and staggered implementation strategies, and qualitative designs. This team grant provides unique opportunities for making important KT methodological developments, with a particular focus on developing a better theoretical understanding of the causal mechanisms and effect modifiers of different KT interventions.Implementation Science 09/2009; 4:60. · 3.10 Impact Factor -
Article: Defining a complex intervention: The development of demarcation criteria for “meditation”.
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ABSTRACT: The authors used a 5-round Delphi study with a panel of 7 experts in meditation research to achieve agreement on a set of criteria for a working definition of “meditation” for use in a comprehensive systematic review of the therapeutic use of meditation. Participants agreed that essential to a meditation practice is its use of (a) a defined technique, (b) logic relaxation, and (c) a self-induced state. Participants also agreed that a meditation practice may (d) involve a state of psychophysical relaxation somewhere in the process; (e) use a self-focus skill or anchor; (f) involve an altered state/mode of consciousness, mystic experience, enlightenment or suspension of logical thought processes; (g) be embedded in a religious/spiritual/philosophical context; or (h) involve an experience of mental silence. The results of this study provide insight into the challenges faced by researchers who want to demarcate meditative practices from nonmeditative practices, and they describe an approach to this problem that may prove useful for researchers trying to operationalize meditation in the context of comparative research. (PsycINFO Database Record (c) 2012 APA, all rights reserved)Psychology of Religion and Spirituality 04/2009; 1(2):129-137. · 1.76 Impact Factor -
Article: Meta-analyses of safety data: a comparison of exact versus asymptotic methods.
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ABSTRACT: The objectives of this study were to establish and describe a database of Cochrane and non-Cochrane meta-analyses of safety data and to determine under what conditions exact methods differ from asymptotic methods in meta-analyses of safety data. A sample of Cochrane (n = 500) and non-Cochrane (n = 200) systematic reviews was randomly selected and a database of safety meta-analyses established. Point estimates and confidence intervals for each meta-analysis were recalculated using exact methods and compared to the results of asymptotic methods. Cochrane reviews were nearly four times as likely as non-Cochrane reviews to contain meta-analyses of safety data (35% compared to 9%). More than 50% of safety meta-analyses contained an outcome with a rare event rate (<5%) and 30% contained at least one study with no events in one arm of the study. For rare event meta-analyses, exact point estimates differed substantially from asymptotic estimates 46% of the time, compared to 17% for those without rare events. Exact confidence intervals differed substantially from asymptotic ones 67% of the time compared to only 19% for those without rare events. The magnitude of differences was also correlated with the number of studies and the summary statistic used to combine the data. Asymptotic methods will not always be a good approximation for exact methods in safety meta-analyses. Event rates and number of studies should be closely examined when choosing the statistical method for combining rare event data.Statistical Methods in Medical Research 06/2008; 18(4):421-32. · 2.44 Impact Factor -
Article: The efficacy and safety of drug treatments for chronic insomnia in adults: a meta-analysis of RCTs.
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ABSTRACT: Hypnotics have a role in the management of acute insomnia; however, the efficacy and safety of pharmacological interventions in the management of chronic insomnia is unclear. The objective of this paper is to conduct a systematic review of the efficacy and safety of drug treatments for chronic insomnia in adults. Twenty-one electronic databases were searched, up to July 2006. Randomized double-blind, placebo-controlled trials were eligible. Quality was assessed using the Jadad scale. Data were pooled using the random effects model. One hundred and five studies were included in the review. Sleep onset latency, as measured by polysomnography, was significantly decreased for benzodiazepines (BDZ), (weighted mean difference: -10.0 minutes; 95% CI: -16.6, -3.4), non-benzodiazepines (non-BDZ) (-12.8 minutes; 95% CI: -16.9, -8.8) and antidepressants (ADP) (-7.0 minutes; 95% CI: -10.7, -3.3). Sleep onset latency assessed by sleep diaries was also improved (BDZ: -19.6 minutes; 95% CI: -23.9, -15.3; non-BDZ: -17.0 minutes; 95% CI: -20.0, -14.0; ADP: -12.2 minutes; 95% CI: -22.3, -2.2). Indirect comparisons between drug categories suggest BDZ and non-BDZ have a similar effect. All drug groups had a statistically significant higher risk of harm compared to placebo (BDZ: risk difference [RD]: 0.15; non-BDZ RD: 0.07; and ADP RD: 0.09), although the most commonly reported adverse events were minor. Indirect comparisons suggest that non-BDZ are safer than BDZ. Benzodiazepines and non-benzodiazepines are effective treatments in the management of chronic insomnia, although they pose a risk of harm. There is also some evidence that antidepressants are effective and that they pose a risk of harm.Journal of General Internal Medicine 10/2007; 22(9):1335-50. · 2.83 Impact Factor -
Article: Meditation practices for health: state of the research.
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ABSTRACT: To review and synthesize the state of research on a variety of meditation practices, including: the specific meditation practices examined; the research designs employed and the conditions and outcomes examined; the efficacy and effectiveness of different meditation practices for the three most studied conditions; the role of effect modifiers on outcomes; and the effects of meditation on physiological and neuropsychological outcomes. Comprehensive searches were conducted in 17 electronic databases of medical and psychological literature up to September 2005. Other sources of potentially relevant studies included hand searches, reference tracking, contact with experts, and gray literature searches. A Delphi method was used to develop a set of parameters to describe meditation practices. Included studies were comparative, on any meditation practice, had more than 10 adult participants, provided quantitative data on health-related outcomes, and published in English. Two independent reviewers assessed study relevance, extracted the data and assessed the methodological quality of the studies. Five broad categories of meditation practices were identified (Mantra meditation, Mindfulness meditation, Yoga, Tai Chi, and Qi Gong). Characterization of the universal or supplemental components of meditation practices was precluded by the theoretical and terminological heterogeneity among practices. Evidence on the state of research in meditation practices was provided in 813 predominantly poor-quality studies. The three most studied conditions were hypertension, other cardiovascular diseases, and substance abuse. Sixty-five intervention studies examined the therapeutic effect of meditation practices for these conditions. Meta-analyses based on low-quality studies and small numbers of hypertensive participants showed that TM(R), Qi Gong and Zen Buddhist meditation significantly reduced blood pressure. Yoga helped reduce stress. Yoga was no better than Mindfulness-based Stress Reduction at reducing anxiety in patients with cardiovascular diseases. No results from substance abuse studies could be combined. The role of effect modifiers in meditation practices has been neglected in the scientific literature. The physiological and neuropsychological effects of meditation practices have been evaluated in 312 poor-quality studies. Meta-analyses of results from 55 studies indicated that some meditation practices produced significant changes in healthy participants. Many uncertainties surround the practice of meditation. Scientific research on meditation practices does not appear to have a common theoretical perspective and is characterized by poor methodological quality. Firm conclusions on the effects of meditation practices in healthcare cannot be drawn based on the available evidence. Future research on meditation practices must be more rigorous in the design and execution of studies and in the analysis and reporting of results.Evidence report/technology assessment 07/2007; -
Article: Transition from meeting abstract to full-length journal article for randomized controlled trials.
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ABSTRACT: Not all research presented at scientific meetings is subsequently published and, even when it is, there may be inconsistencies between these results and what is ultimately printed. Although late-breaking trials sessions are now integrated into several major scientific meetings and the results are often promptly and prominently communicated, no studies have examined the publication fate and degree of consistency between meeting abstracts or presentations and subsequent full-length article publications for randomized controlled trials (RCTs) presented at these sessions. To compare RCT abstracts presented in the late-breaking trials session vs other sessions at a major scientific meeting and subsequent full-length publications. RCTs were identified by hand searching abstract proceedings booklets and related Web sites for the American College of Cardiology scientific meetings (1999-2002). Subsequent full-length articles were identified via electronic databases. Publication fate and degree of consistency between meeting abstract results and subsequent full-length publication results. The 86 late-breaking RCTs were significantly larger (median, 2737 patients vs 896; P<.001), were more likely to be preceded by a published design paper (27 [31%] vs 13 [13%]; P = .002), had higher quality scores when eventually published (mean Jadad score 2.69 vs 2.19; P = .01), and were less likely to report favorable results for the intervention than the 100 randomly chosen comparison RCTs presented in other sessions (50 [58%] vs 75 [75%]; P = .01; odds ratio 0.46; 95% confidence interval, 0.24-0.90). RCTs presented at the late-breaking trials sessions were significantly more likely to be published (79 [92%] vs 69 [69%]; P<.001) and appeared earlier after presentation (median 11.5 months vs 22.0 months; P<.001) than RCTs presented in other sessions, an association that persisted even after adjusting for sample size, conclusion of study, and RCT design: adjusted hazard ratio, 1.80 (95% confidence interval, 1.24-2.61). Sixty (41%) of the 148 RCTs that were subsequently published exhibited discrepancies between the efficacy estimate reported in the meeting abstract vs the one reported in the full-length article for the primary outcome. The mean change in effect was 0.44 SDs and in 20 cases (14%), the point estimate was statistically significant in only 1 member of the pair. The discrepancy rate was the same for late-breaking RCTs as for RCTs presented in other American College of Cardiology sessions (P = .92). Late-breaking trials were larger, more likely to be preceded by a design paper, and less likely to report positive results than RCTs presented at other sessions, but discrepancies between the meeting abstract results and subsequent full-length publication results were common even for late-breaking trials.JAMA The Journal of the American Medical Association 04/2006; 295(11):1281-7. · 30.03 Impact Factor -
Article: The Cochrane Library and the Treatment of Bronchiolitis in Children: An Overview of Reviews
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ABSTRACT: BackgroundBronchiolitis describes a viral inflammation of the bronchioles in the lower respiratory tract that is typically caused by infection with respiratory syncytial virus (RSV). Bronchiolitis is characterized by high morbidity and affects approximately one in three infants. Children are currently treated with a variety of therapies that may be ineffective or even harmful; potential therapies include antibiotics, bronchodilators, chest physiotherapy, epinephrine, extrathoracic pressure, glucocorticoids, heliox, hypertonic saline, immunoglobulin, inhaled corticosteroids and oxygen therapy.ObjectivesThis updated overview of reviews aims to synthesize evidence from the Cochrane Database of Systematic Reviews (CDSR) on the effectiveness and safety of 11 pharmacologic and non-pharmacologic treatments to improve bronchiolitis symptoms in outpatient, inpatient and intensive care populations.MethodsThe CDSR was searched using the term ‘bronchiolitis’ restricted to the title, abstract or keywords for all systematic reviews examining pharmacologic or non-pharmacologic interventions for the treatment of bronchiolitis in infants and children. Data were extracted, complied into tables, and synthesized using qualitative and quantitative methods.Main ResultsFor outpatients with bronchiolitis (defined as the first episode of wheezing in children under two), nebulized epinephrine decreased hospitalization rate on day one by 33% (RR: 0.67; 95% CI: 0.50, 0.89; 4 trials; 920 participants). With the addition of glucocorticoids, there was a reduction of similar magnitude for hospitalization rate within seven days (RR: 0.65; 95% CI: 0.44, 0.95; 1 trial; 400 participants). For inpatients, nebulized epinephrine versus bronchodilator and 3% hypertonic saline versus 0.9% saline each decreased length of stay: epinephrine decreased length of stay by seven hours (MD: − 0.28; 95% CI: − 0.46, − 0.09; 4 trials; 261 participants), and 3% hypertonic saline decreased length of stay by 28 hours (MD: − 1.16; 95% CI: − 1.55, − 0.77; 4 trials; 282 participants).Outpatients treated with epinephrine or epinephrine and glucocorticoid combined both had significantly lower clinical scores at 60 minutes (SMD: − 0.45; 95% CI: − 0.66, − 0.23; 4 trials; 900 participants, and SMD: − 0.34; 95% CI: − 0.54, − 0.14; 1 trial; 399 participants). For inpatients, epinephrine versus bronchodilator led to a significantly lower clinical score at both 60 minutes (SMD: − 0.79; 95% CI: − 1.45, − 0.13; 4 trials; 248 participants; I2: 79%) and 120 minutes (SMD: − 0.52; 95% CI: − 0.86, − 0.18; 1 trial; 140 participants). Inpatients treated with chest physiotherapy or 3% hypertonic saline both had significantly lower clinical scores at 1–3 days (SMD: − 0.55; 95% CI: − 0.98, − 0.12; 1 trial; 87 participants, and SMD: − 0.84; 95% CI: − 1.39, − 0.30; 3 trials; 183 participants).Authors' ConclusionsFor outpatients with bronchiolitis, nebulized epinephrine can be effective in avoiding hospitalization. Systemic glucocorticoids such as dexamethasone cannot be recommended as a routine therapy given the current level of evidence and potential for adverse events. For inpatients, regular nebulized hypertonic saline (3%) driven using oxygen may reduce the length of hospital stay. Chest physiotherapy, nebulized epinephrine and systemic and inhaled glucocorticoids cannot be recommended for inpatients given the weak level of evidence. For the sickest of patients in the intensive care unit, intravenous immunoglobulin, helium-oxygen mixtures (heliox) and extrathoracic pressure cannot be recommended due to lack of available evidence and/or methodological flaws of reviews. Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. The Cochrane CollaborationEvidence-Based Child Health: A Cochrane Review Journal. 6(1):258-275.
