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Jeffrey C Andrews,
Holger J Schünemann,
Andrew D Oxman,
Kevin Pottie,
Joerg J Meerpohl,
Pablo Alonso Coello,
David Rind, Victor Montori,
Juan Pablo Brito Campana,
Susan Norris,
Mahmoud Elbarbary,
Piet Post,
Mona Nasser,
Vijay Shukla,
Roman Jaeschke,
Jan Brozek,
Ben Djulbegovic,
Gordon Guyatt
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ABSTRACT: In the GRADE approach, the strength of a recommendation reflects the extent to which we can be confident that the composite desirable effects of a management strategy outweigh the composite undesirable effects. This article addresses GRADE's approach to determining the direction and strength of a recommendation. The GRADE describes the balance of desirable and undesirable outcomes of interest among alternative management strategies depending on four domains, namely estimates of effect for desirable and undesirable outcomes of interest, confidence in the estimates of effect, estimates of values and preferences, and resource use. Ultimately, guideline panels must use judgment in integrating these factors to make a strong or weak recommendation for or against an intervention.
Journal of clinical epidemiology 04/2013; · 2.96 Impact Factor
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Gordon Guyatt,
Andrew D Oxman,
Shahnaz Sultan,
Jan Brozek,
Paul Glasziou,
Pablo Alonso-Coello,
David Atkins,
Regina Kunz, Victor Montori,
Roman Jaeschke,
David Rind,
Philipp Dahm,
Elie A Akl,
Joerg Meerpohl,
Gunn Vist,
Elise Berliner,
Susan Norris,
Yngve Falck-Ytter,
Holger J Schünemann
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ABSTRACT: GRADE requires guideline developers to make an overall rating of confidence in estimates of effect (quality of evidence-high, moderate, low, or very low) for each important or critical outcome. GRADE suggests, for each outcome, the initial separate consideration of five domains of reasons for rating down the confidence in effect estimates, thereby allowing systematic review authors and guideline developers to arrive at an outcome-specific rating of confidence. Although this rating system represents discrete steps on an ordinal scale, it is helpful to view confidence in estimates as a continuum, and the final rating of confidence may differ from that suggested by separate consideration of each domain. An overall rating of confidence in estimates of effect is only relevant in settings when recommendations are being made. In general, it is based on the critical outcome that provides the lowest confidence.
Journal of clinical epidemiology 04/2012; · 2.96 Impact Factor
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Gordon H Guyatt,
Andrew D Oxman,
Shahnaz Sultan,
Paul Glasziou,
Elie A Akl,
Pablo Alonso-Coello,
David Atkins,
Regina Kunz,
Jan Brozek, Victor Montori,
Roman Jaeschke,
David Rind,
Philipp Dahm,
Joerg Meerpohl,
Gunn Vist,
Elise Berliner,
Susan Norris,
Yngve Falck-Ytter,
M Hassan Murad,
Holger J Schünemann
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ABSTRACT: The most common reason for rating up the quality of evidence is a large effect. GRADE suggests considering rating up quality of evidence one level when methodologically rigorous observational studies show at least a two-fold reduction or increase in risk, and rating up two levels for at least a five-fold reduction or increase in risk. Systematic review authors and guideline developers may also consider rating up quality of evidence when a dose-response gradient is present, and when all plausible confounders or biases would decrease an apparent treatment effect, or would create a spurious effect when results suggest no effect. Other considerations include the rapidity of the response, the underlying trajectory of the condition, and indirect evidence.
Journal of clinical epidemiology 07/2011; 64(12):1311-6. · 2.96 Impact Factor
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Gordon H Guyatt,
Andrew D Oxman, Victor Montori,
Gunn Vist,
Regina Kunz,
Jan Brozek,
Pablo Alonso-Coello,
Ben Djulbegovic,
David Atkins,
Yngve Falck-Ytter,
John W Williams,
Joerg Meerpohl,
Susan L Norris,
Elie A Akl,
Holger J Schünemann
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ABSTRACT: In the GRADE approach, randomized trials start as high-quality evidence and observational studies as low-quality evidence, but both can be rated down if a body of evidence is associated with a high risk of publication bias. Even when individual studies included in best-evidence summaries have a low risk of bias, publication bias can result in substantial overestimates of effect. Authors should suspect publication bias when available evidence comes from a number of small studies, most of which have been commercially funded. A number of approaches based on examination of the pattern of data are available to help assess publication bias. The most popular of these is the funnel plot; all, however, have substantial limitations. Publication bias is likely frequent, and caution in the face of early results, particularly with small sample size and number of events, is warranted.
Journal of clinical epidemiology 07/2011; 64(12):1277-82. · 2.96 Impact Factor
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Gordon H Guyatt,
Andrew D Oxman,
Gunn Vist,
Regina Kunz,
Jan Brozek,
Pablo Alonso-Coello, Victor Montori,
Elie A Akl,
Ben Djulbegovic,
Yngve Falck-Ytter,
Susan L Norris,
John W Williams,
David Atkins,
Joerg Meerpohl,
Holger J Schünemann
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ABSTRACT: In the GRADE approach, randomized trials start as high-quality evidence and observational studies as low-quality evidence, but both can be rated down if most of the relevant evidence comes from studies that suffer from a high risk of bias. Well-established limitations of randomized trials include failure to conceal allocation, failure to blind, loss to follow-up, and failure to appropriately consider the intention-to-treat principle. More recently recognized limitations include stopping early for apparent benefit and selective reporting of outcomes according to the results. Key limitations of observational studies include use of inappropriate controls and failure to adequately adjust for prognostic imbalance. Risk of bias may vary across outcomes (e.g., loss to follow-up may be far less for all-cause mortality than for quality of life), a consideration that many systematic reviews ignore. In deciding whether to rate down for risk of bias--whether for randomized trials or observational studies--authors should not take an approach that averages across studies. Rather, for any individual outcome, when there are some studies with a high risk, and some with a low risk of bias, they should consider including only the studies with a lower risk of bias.
Journal of clinical epidemiology 04/2011; 64(4):407-15. · 2.96 Impact Factor
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Meghan Pierce,
Erik Hess,
Jeffrey Kline,
Nilay Shah,
Maggie Breslin,
Megan Branda,
Laurie Pencille,
Brent Asplin,
David Nestler,
Annie Sadosty,
Ian Stiell,
Henry Ting, Victor Montori
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ABSTRACT: Abstract
Background
Chest pain is a common presenting complaint in the emergency department (ED). Despite the frequency with which clinicians evaluate patients with chest pain, accurately determining the risk of acute coronary syndrome (ACS) and sharing risk information with patients is challenging. The aims of this study are (1) to develop a decision aid ( CHEST PAIN CHOICE ) that communicates the short-term risk of ACS and (2) to evaluate the impact of the decision aid on patient participation in decision-making and resource use.
Methods/Design
This is a protocol for a parallel, 2-arm randomized trial to compare an intervention group receiving CHEST PAIN CHOICE to a control group receiving usual ED care. Adults presenting to the Saint Mary's Hospital ED in Rochester, MN USA with a primary complaint of chest pain who are being considered for admission for prolonged ED observation in a specialized unit and urgent cardiac stress testing will be eligible for enrollment. We will measure the effect of CHEST PAIN CHOICE on six outcomes: (1) patient knowledge regarding their short-term risk for ACS and the risks of radiation exposure; (2) quality of the decision making process; (3) patient and clinician acceptability and satisfaction with the decision aid; (4) the proportion of patients who decided to undergo observation unit admission and urgent cardiac stress testing; (5) economic costs and healthcare utilization; and (6) the rate of delayed or missed ACS. To capture these outcomes, we will administer patient and clinician surveys after each visit, obtain video recordings of the clinical encounters, and conduct 30-day phone follow-up.
Discussion
This pilot randomized trial will develop and evaluate a decision aid for use in ED chest pain patients at low risk for ACS and provide a preliminary estimate of its effect on patient participation in decision-making and resource use.
Trial registration
Clinical Trials.gov Identifier: NCT01077037
Trials. 01/2010;
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Rajesh Hiralal,
Gordon Guyatt,
Mohit Bhandari,
Deborah Cook,
Otavio Berwanger,
Justin De Beer,
Claudio Cina,
Norm Buckley,
Juan Carlos Villar, Victor Montori,
Michael Marcaccio,
James Paul,
Laura Whiteacre,
P J Devereaux
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ABSTRACT: Major cardiovascular complications associated with noncardiac surgery represent a substantial population health problem for which there are no established efficacious and safe prophylactic interventions. Acetyl-salicylic acid (ASA) represents a promising intervention. The objective of this study was to determine surgeons' perioperative usage of ASA, and if they would enroll their patients in a perioperative ASA randomized controlled trial (RCT).
Cross-sectional survey of all practicing Canadian general, orthopedic, and vascular surgeons. Our mailed, self-administered survey asked surgeons to consider only their patients who were at risk of a major perioperative cardiovascular complication.
The response rate was 906/1854 (49%). For patients taking ASA chronically, there was marked variability regarding ASA continuation prior to surgery amongst the general and orthopedic surgeons, whereas 76% of vascular surgeons continued ASA in 81-100% of their patients. For patients not taking ASA chronically, approaches to starting ASA prior to surgery were variable amongst the vascular surgeons, whereas 70% of general and 82% of orthopaedic surgeons did not start ASA. For patients taking ASA chronically, 73% of general surgeons, 70% of orthopaedic surgeons, and 36% of vascular surgeons would allow at least 40% of their patients to participate in a perioperative RCT comparing stopping versus continuing ASA. For patients not taking ASA chronically, most general (76%), orthopaedic (67%), and vascular (51%) surgeons would allow at least 40% of their patients to participate in a perioperative RCT comparing starting ASA versus placebo.
This national survey demonstrates that perioperative ASA usage as reported by surgeons is variable, identifying the need for, and community interest in, a large perioperative ASA trial.
Clinical and investigative medicine. Medecine clinique et experimentale 01/2010; 33(6):E375-83. · 1.15 Impact Factor
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ABSTRACT: Abstract Systematic reviews of randomized trials that include measurements of health-related quality of life potentially provide critical information for patient and clinicians facing challenging health care decisions. When, as is most often the case, individual randomized trials use different measurement instruments for the same construct (such as physical or emotional function), authors typically report differences between intervention and control in standard deviation units (so-called "standardized mean difference" or "effect size"). This approach has statistical limitations (it is influenced by the heterogeneity of the population) and is non-intuitive for decision makers. We suggest an alternative approach: reporting results in minimal important difference units (the smallest difference patients experience as important). This approach provides a potential solution to both the statistical and interpretational problems of existing methods.
Health and Quality of Life Outcomes. 01/2010;
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Laurie Pencille,
Megan Campbell,
Van Houten Holly,
Nilay Shah,
Rebecca Mullan,
Brian Swiglo,
Maggie Breslin,
Rebecca Kesman,
Sidna Tulledge-Scheitel,
Thomas Jaeger,
Ruth Johnson,
Gregory Bartel,
Robert Wermers,
Melton L Joseph, Victor Montori
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ABSTRACT: Abstract
Background
Bisphosphonates can reduce fracture risk in patients with osteoporosis, but many at-risk patients do not start or adhere to these medications. The aims of this study are to: (1) preliminarily evaluate the effect of an individualized 10-year osteoporotic fracture risk calculator and decision aid ( O STEOPOROSIS CHOICE ) for postmenopausal women at risk for osteoporotic fractures; and (2) assess the feasibility and validity (i.e., absence of contamination) of patient-level randomization (vs. cluster randomization) in pilot trials of decision aid efficacy.
Methods/Design
This is a protocol for a parallel, 2-arm, randomized trial to compare an intervention group receiving O STEOPOROSIS CHOICE to a control group receiving usual primary care. Postmenopausal women with bone mineral density T-scores of <-1.0, not receiving bisphosphonate therapy, and receiving care at participating primary care practices in and around Rochester, Minnesota, USA will be eligible to participate in the trial. We will measure the effect of O STEOPOROSIS CHOICE on five outcomes: (a) patient knowledge regarding osteoporosis risk factors and treatment; (b) quality of the decision-making process for both the patient and clinician; (c) patient and clinician acceptability and satisfaction with the decision aid; (d) rate of bisphosphonate use and adherence, and (e) trial processes (e.g., ability to recruit participants, collect patient outcomes). To capture these outcomes, we will use patient and clinician surveys following each visit and video recordings of the clinical encounters. These video recordings will also allow us to determine the extent to which clinicians previously exposed to the decision aid were able to recreate elements of the decision aid with control patients (i.e., contamination). Pharmacy prescription profiles and follow-up phone interviews will assess medication start and adherence at 6 months.
Discussion
This pilot trial will provide evidence of feasibility, validity of patient randomization, and preliminary efficacy of a novel approach -- decision aids -- to improving medication adherence for postmenopausal women at risk of osteoporotic fractures. The results will inform the design of a larger trial that could provide more precise estimates of the efficacy of the decision aid.
Trial registration
Clinical Trials.gov Identifier: NCT00578981
Trials. 01/2009;
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Pablo Alonso-Coello, Victor M Montori,
Ivan Solà,
Holger J Schünemann,
Philipe Devereaux,
Cathy Charles,
Mercè Roura,
M Gloria Díaz,
Juan Carlos Souto,
Rafael Alonso,
Sven Oliver,
Rafael Ruiz,
Blanca Coll-Vinent,
Ana Isabel Diez,
Ignasi Gich,
Gordon Guyatt
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ABSTRACT: Oral anticoagulation prevents strokes in patients with atrial fibrillation but, for reasons that remain unclear, less than 40% of all patients with atrial fibrillation receive warfarin. The literature postulates that patient and clinician preferences may explain this low utilization.
The proposed research seeks to answer the following questions: i) When assessed systematically, do patients' and clinicians' preferences explain the utilization of warfarin to prevent strokes associated with atrial fibrillation? ii) To what extent do patients' and clinicians' treatment preferences differ? iii) What factors explain any differences that exist in treatment preferences between patients and clinicians? To answer these questions we will conduct a two-phase study of patient and clinician preferences for health states and treatments. In the first phase of this study we will conduct structured interviews to determine their treatment preferences for warfarin vs. aspirin to prevent strokes associated with atrial fibrillation using the probability trade-off technique. In the same interview, we will conduct preference-elicitation exercises using the feeling thermometer to identify the utilities that patients place on taking medication (warfarin and aspirin), and on having a mild stroke, a severe stroke, and a major bleed. In the second phase of the study we will convene focus groups of clinicians and patients to explore their answers to the exercises in the first phase.
This is a study of patient and clinician preferences for health states and treatments. Because of its clinical importance and our previous work in this area, we will conduct our study in the clinical context of the decision to use antithrombotic agents to reduce the risk of stroke in patients with non-valvular chronic atrial fibrillation.
BMC Health Services Research 11/2008; 8:221. · 1.66 Impact Factor
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Journal of General Internal Medicine 04/2008; 23(3):337-43. · 2.83 Impact Factor
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ABSTRACT: Different presentations of treatment effects can affect decisions. However, previous studies have not evaluated which presentations best help people make decisions that are consistent with their own values. We undertook a pilot study to compare different methods for doing this.
We conducted an Internet-based randomized trial comparing summary statistics for communicating the effects of statins on the risk of coronary heart disease (CHD). Participants rated the relative importance of treatment consequences using visual analogue scales (VAS) and category rating scales (CRS) with five response options. We randomized participants to either VAS or CRS first and to one of six summary statistics: relative risk reduction (RRR) and five absolute measures of effect: absolute risk reduction, number needed to treat, event rates, tablets needed to take, and natural frequencies (whole numbers). We used logistic regression to determine the association between participants' elicited values and treatment choices. 770 participants age 18 or over and literate in English completed the study. In all, 13% in the VAS-first group failed to complete their VAS rating, while 9% of the CRS-first group failed to complete their scoring (p = 0.03). Different ways of weighting the elicited values had little impact on the analyses comparing the different presentations. Most (51%) preferred the RRR compared to the other five summary statistics (1% to 25%, p = 0.074). However, decisions in the group presented the RRR deviated substantially from those made in the other five groups. The odds of participants in the RRR group deciding to take statins were 3.1 to 5.8 times that of those in the other groups across a wide range of values (p = 0.0007). Participants with a scientific background, who were more numerate or had more years of education were more likely to decide not to take statins.
Internet-based trials comparing different presentations of treatment effects are feasible, but recruiting participants is a major challenge. Despite a slightly higher response rate for CRS, VAS is preferable to avoid approximation of a continuous variable. Although most participants preferred the RRR, participants shown the RRR were more likely to decide to take statins regardless of their values compared with participants who were shown any of the five other summary statistics.
Controlled-Trials.com ISRCTN85194921.
PLoS ONE 02/2008; 3(11):e3693. · 4.09 Impact Factor
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Journal of General Internal Medicine 01/2008; 23(3):337-343. · 2.83 Impact Factor
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ABSTRACT: Abstract
Background
Decision aids (DA) are tools designed to help patients make specific and deliberative choices among disease management options. DAs can improve the quality of decision-making and reduce decisional conflict. An area not covered by a DA is the decision of a patient with chronic obstructive pulmonary disease (COPD) to use inhaled steroids which requires balancing the benefits and downsides of therapy.
Methods
We developed a DA for COPD patients considering inhaled steroid therapy using the Ottawa Decision Support Framework, the best available evidence for using inhaled steroid in COPD and the expected utility model. The development process involved patients, pulmonologists, DA developers and decision making experts. We pilot tested the DA with 8 COPD patients who completed an evaluation questionnaire, a knowledge scale, and a validated decisional conflict scale.
Results
The DA is a computer-based interactive tool incorporating four different decision making models. In the first part, the DA provides information about COPD as a disease, the different treatment options, and the benefits and downsides of using inhaled steroids. In the second part, it coaches the patient in the decision making process through clarifying values and preferences. Patients evaluated 10 out of 13 items of the DA positively and showed significant improvement on both the knowledge scale (p = 0.008) and the decisional conflict scale (p = 0.008).
Conclusion
We have developed a computer-based interactive DA for COPD patients considering inhaled steroids serving as a model for other DAs in COPD, in particular related to inhaled therapies. Future research should assess the DA effectiveness.
BMC Medical Informatics and Decision Making. 01/2007;
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ABSTRACT: Tumor necrosis factor (TNF) plays an important role in host defense and tumor growth control. Therefore, anti-TNF antibody therapies may increase the risk of serious infections and malignancies.
To assess the extent to which anti-TNF antibody therapies may increase the risk of serious infections and malignancies in patients with rheumatoid arthritis by performing a meta-analysis to derive estimates of sparse harmful events occurring in randomized trials of anti-TNF therapy.
A systematic literature search of EMBASE, MEDLINE, Cochrane Library, and electronic abstract databases of the annual scientific meetings of both the European League Against Rheumatism and the American College of Rheumatology was conducted through December 2005. This search was complemented with interviews of the manufacturers of the 2 licensed anti-TNF antibodies.
We included randomized, placebo-controlled trials of the 2 licensed anti-TNF antibodies (infliximab and adalimumab) used for 12 weeks or more in patients with rheumatoid arthritis. Nine trials met our inclusion criteria, including 3493 patients who received anti-TNF antibody treatment and 1512 patients who received placebo.
Data on study characteristics to assess study quality and intention-to-treat data for serious infections and malignancies were abstracted. Published information from the trials was supplemented by direct contact between principal investigators and industry sponsors.
We calculated a pooled odds ratio (Mantel-Haenszel methods with a continuity correction designed for sparse data) for malignancies and serious infections (infection that requires antimicrobial therapy and/or hospitalization) in anti-TNF-treated patients vs placebo patients. We estimated effects for high and low doses separately. The pooled odds ratio for malignancy was 3.3 (95% confidence interval [CI], 1.2-9.1) and for serious infection was 2.0 (95% CI, 1.3-3.1). Malignancies were significantly more common in patients treated with higher doses compared with patients who received lower doses of anti-TNF antibodies. For patients treated with anti-TNF antibodies in the included trials, the number needed to harm was 154 (95% CI, 91-500) for 1 additional malignancy within a treatment period of 6 to 12 months. For serious infections, the number needed to harm was 59 (95% CI, 39-125) within a treatment period of 3 to 12 months.
There is evidence of an increased risk of serious infections and a dose-dependent increased risk of malignancies in patients with rheumatoid arthritis treated with anti-TNF antibody therapy. The formal meta-analysis with pooled sparse adverse events data from randomized controlled trials serves as a tool to assess harmful drug effects.
JAMA The Journal of the American Medical Association 06/2006; 295(19):2275-85. · 30.03 Impact Factor
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ABSTRACT: The use of natural health products (NHPs) within the HIV community is high. Several NHPs have demonstrated interactions with HIV medications that could contribute to drug failure. We aimed to conduct a systematic review of clinical trials examining NHP-HIV drug interactions and their methodological characteristics. We searched electronic databases and unpublished resources independently, in duplicate. Nine studies were identified, eight clinical pharmacokinetics trials and one population-pharmacokinetics trial. Investigators studied four different herbal medicines (St John's wort, garlic, goldenseal and milk thistle) and one vitamin (vitamin C). Significant interactions were observed with St John's wort, garlic and vitamin C. However, methodological challenges exist to making the results directly generalizable to patients. This review finds that important drug level changes exist when NHPs are combined with HIV medications. Considering patient values and the implications of these studies, further research is urgently required to determine the extent of interactions with other commonly used NHPs.
International Journal of STD & AIDS 04/2005; 16(3):181-6. · 1.09 Impact Factor
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ABSTRACT: To compare response rate, time to response, and data quality of electronic and postal surveys in the setting of postgraduate medical education.
A randomized controlled trial in a university-based internal medicine residency program. We randomized 119 residents and 83 faculty to an electronic versus a postal survey with up to two reminders and measured response rate, time to response, and data quality.
For residents, the e-survey resulted in a lower response rate than the postal survey (63.3% versus 79.7%; difference -16.3%, 95% confidence interval (95% CI) -32.3% to -0.4%%; P=.049), but a shorter mean response time, by 3.8 days (95% CI 0.2-7.4; P=.042). For faculty, the e-survey did not result in a significantly lower response rate than the postal survey (85.4% vs. 81.0%; difference 4.4%, 95% CI -11.7 to 20.5%; P=.591), but resulted in a shorter average response time, by 8.4 days (95% CI 4.4 to 12.4; P < 0.001). There were no differences in the quality of data or responses to the survey between the two methods.
E-surveys were not superior to postal surveys in terms of response rate, but resulted in shorter time to response and equivalent data quality.
Journal of Clinical Epidemiology 04/2005; 58(4):425-9. · 4.27 Impact Factor
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Canadian Medical Association Journal 09/2004; 171(4):347-8. · 8.22 Impact Factor
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Canadian journal of surgery. Journal canadien de chirurgie 03/2004; 47(1):60-7. · 1.05 Impact Factor
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ABSTRACT: To examine surgical trainees' barriers to implementing and adopting evidence-based medicine (EBM) in the day-to-day care of surgical patients.
In 2000, 28 surgical residents from various subspecialties at a hospital affiliated with McMaster University Faculty of Health Sciences in Ontario, Canada, participated in a focus group (n = 8) and semistructured interviews (n = 20) to explore their perceptions of barriers to the practice of EBM during their training. Additional themes were explored, such as definitions of EBM and potential strategies to implement EBM during training. The canons and procedures of the grounded theory approach to qualitative research guided the coding and content analysis of the data derived from the focus group and semistructured interviews.
Residents identified personal barriers, staff-surgeon barriers, and institutional barriers that limited their ability to apply EBM in their daily activities. Residents perceived their lack of education in EBM, time constraints, lack of priority, and fear of staff disapproval as major challenges to practicing EBM. Moreover, the lack of ready access to surgical EBM resource materials proved to be an important additional factor limiting EBM surgical practice. Residents identified several strategies to overcome these barriers to EBM, including hiring staff surgeons with EBM training, offering coursework in critical appraisal for all staff, improving interdepartmental communication, and providing greater flexibility for EBM training.
Surgical residents identified a general lack of education, time constraints, lack of priority, and staff disapproval as important factors limiting incorporation of EBM. Curriculum reform and surgeon education may help overcome these barriers.
Academic Medicine 12/2003; 78(11):1183-90. · 3.52 Impact Factor
