Browsing by Author "Ebrahim, Shanil"

Now showing 1 - 8 of 8
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    A methodological survey of the analysis, reporting and interpretation of Absolute Risk ReductiOn in systematic revieWs (ARROW): a study protocol
    (2013) Alonso-Coello, Pablo; Carrasco-Labra, Alonso; Brignardello-Petersen, Romina; Neumann Burotto, Gonzalo Ignacio; Akl, Elie A; Sun, Xin; Johnston, Bradley C; Briel, Matthias; Busse, Jason W; Glujovsky, Demián; Granados, Carlos E; Iorio, Alfonso; Irfan, Affan; García, Laura M; Mustafa, Reem A; Ramirez-Morera, Anggie; Solà, Iván; Tikkinen, Kari A O; Ebrahim, Shanil; Vandvik, Per O; Zhang, Yuqing; Selva, Anna; Sanabria, Andrea J; Zazueta, Oscar E; Vernooij, Robin W M; Schünemann, Holger J; Guyatt, Gordon H
    Abstract Background Clinicians, providers and guideline panels use absolute effects to weigh the advantages and downsides of treatment alternatives. Relative measures have the potential to mislead readers. However, little is known about the reporting of absolute measures in systematic reviews. The objectives of our study are to determine the proportion of systematic reviews that report absolute measures of effect for the most important outcomes, and ascertain how they are analyzed, reported and interpreted. Methods/design We will conduct a methodological survey of systematic reviews published in 2010. We will conduct a 1:1 stratified random sampling of Cochrane vs. non-Cochrane systematic reviews. We will calculate the proportion of systematic reviews reporting at least one absolute estimate of effect for the most patient-important outcome for the comparison of interest. We will conduct multivariable logistic regression analyses with the reporting of an absolute estimate of effect as the dependent variable and pre-specified study characteristics as the independent variables. For systematic reviews reporting an absolute estimate of effect, we will document the methods used for the analysis, reporting and interpretation of the absolute estimate. Discussion Our methodological survey will inform current practices regarding reporting of absolute estimates in systematic reviews. Our findings may influence recommendations on reporting, conduct and interpretation of absolute estimates. Our results are likely to be of interest to systematic review authors, funding agencies, clinicians, guideline developers and journal editors.
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    Completion and publication rates of randomized controlled trials in surgery an empirical study
    (2015) Rosenthal, Rachel; Kasenda, Benjamin; Dell-Kuster, Salome; Von Elm, Erik; You, John; Neumann Burotto, Gonzalo Ignacio; Tomonaga, Yuki; Saccilotto, Ramon; Amstutz, Alain; Bengough, Theresa; Meerpohl, Joerg J.; Stegert, Mihaela; Tikkinen, Kari A. O.; Blümle, Anette; Carrasco-Labra, Alonso; Faulhaber, Markus; Mulla, Sohail; Mertz, Dominik; Akl, Elie A.; Bassler, Dirk; Busse, Jason W.; Ferreira-González, Ignacio; Lamontagne, Francois; Nordmann, Alain; Gloy, Viktoria; Olu, Kelechi K.; Raatz, Heike; Moja, Lorenzo; Ebrahim, Shanil; Schandelmaier, Stefan; Sun, Xin; Vandvik, Per O.; Johnston, Bradley C.; Walter, Martin A.; Burnand, Bernard; Schwenkglenks, Matthias; Hemkens, Lars G.; Bucher, Heiner C.; Guyatt, Gordon H.; Briel, Matthias
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    Evaluating patient values and preferences for thromboprophylaxis decision making during pregnancy: a study protocol
    (2012) Alonso Coello, Pablo.; Neumann Burotto, Gonzalo Ignacio; Ebrahim, Shanil; Guyatt, Gordon H.; Tikkinen, Kari A.; Eckman, Mark H.; McDonald, Sarah D.; Akl, Elie A.; Bates, Shannon M.
    Abstract Background Pregnant women with prior venous thromboembolism (VTE) are at risk of recurrence. Low molecular weight heparin (LWMH) reduces the risk of pregnancy-related VTE. LMWH prophylaxis is, however, inconvenient, uncomfortable, costly, medicalizes pregnancy, and may be associated with increased risks of obstetrical bleeding. Further, there is uncertainty in the estimates of both the baseline risk of pregnancy-related recurrent VTE and the effects of antepartum LMWH prophylaxis. The values and treatment preferences of pregnant women, crucial when making recommendations for prophylaxis, are currently unknown. The objective of this study is to address this gap in knowledge. Methods We will perform a multi-center cross-sectional interview study in Canada, USA, Norway and Finland. The study population will consist of 100 women with a history of lower extremity deep vein thrombosis (DVT) or pulmonary embolism (PE), and who are either pregnant, planning pregnancy, or may in the future consider pregnancy (women between 18 and 45 years). We will exclude individuals who are on full dose anticoagulation or thromboprophylaxis, who have undergone surgical sterilization, or whose partners have undergone vasectomy. We will determine each participant's willingness to receive LMWH prophylaxis during pregnancy through direct choice exercises based on real life and hypothetical scenarios, preference-elicitation using a visual analog scale (“feeling thermometer”), and a probability trade-off exercise. The primary outcome will be the minimum reduction (threshold) in VTE risk at which women change from declining to accepting LMWH prophylaxis. We will explore possible determinants of this choice, including educational attainment, the characteristics of the women’s prior VTE, and prior experience with LMWH. We will determine the utilities that women place on the burden of LMWH prophylaxis, pregnancy-related DVT, pregnancy-related PE and pregnancy-related hemorrhage. We will generate a “personalized decision analysis” using participants’ utilities and their personalized risk of recurrent VTE as inputs to a decision analytic model. We will compare the personalized decision analysis to the participant’s stated choice. Discussion The preferences of pregnant women at risk of VTE with respect to the use of antithrombotic therapy remain unexplored. This research will provide explicit, quantitative expressions of women's valuations of health states related to recurrent VTE and its prevention with LMWH. This information will be crucial for both guideline developers and for clinicians.
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    Reporting handling and assessing the risk of bias associated with missing participant data in systematic reviews : a methodological survey
    (2015) Akl, Elie A.; Carrasco Labra, Alonso; Brignardello Petersen, Romina; Neumann Burotto, Gonzalo Ignacio; Johnston, Bradley C.; Sun, Xin; Briel, Matthias; Busse, Jason W; Ebrahim, Shanil; Granados, Carlos; Iorio, Alfonso; Irfan, Affan; Martínez García, Laura; Mustafa, Reem A.; Ramírez Morera, Anggie; Selva, Anna; Solà, Ivan; Sanabria, Andrea Juliana; Tikkinen, Kari A. O.; Vandvik, Per O.; Vernooij, Robin W. M.; Zazueta, Oscar E.; Zhou, Qi; Guyatt, Gordon H.; Alonso Coello, Pablo
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    Reporting missing participant data in randomised trials : systematic survey of the methodological literature and a proposed guide
    (2015) Akl, Elie A.; Shawwa, Khled; Kahale, Lara A.; Agoritsas, Thomas; Brignardello Petersen, Romina; Busse, Jason W.; Carrasco Labra, Alonso; Ebrahim, Shanil; Johnston, Bradley C.; Neumann Burotto, Gonzalo Ignacio; Sola, Ivan; Sun, Xin; Vandvik, Per; Zhang, Yuqing; Alonso Coello, Pablo; Guyatt, Gordon H.
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    Systematic Review of Observational Studies Assessing Bleeding Risk in Patients with Atrial Fibrillation Not Using Anticoagulants
    (2014) Cruz Lopes, Luciane; Spencer, Frederick A.; Neumann Burotto, Gonzalo Ignacio; Ventresca, Matthew; Ebrahim, Shanil; Zhou, Qi; Bhatnagar, Neera; Schulman, Sam; Eikelboom, John; Guyatt, Gordon
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    Women's values and preferences and health state valuations for thromboprophylaxis during pregnancy : A cross-sectional interview study
    (2016) Bates, Shannon M.; Alonso Coello, Pablo; Tikkinen, Kari A. O.; Ebrahim, Shanil; Cruz Lopes, Luciane; McDonald, Sarah D.; Qi Zhou; Akl, Elie A.; Neumann Burotto, Gonzalo Ignacio; Jacobsen, Anne Flem; Yuqing Zhang; Santamaría, Amparo; Annichino Bizzacchi, Joyce Maria; Morten Sandset, Per; Bitar, Wael; Eckman, Mark H.; Guyatt, Gordon H.
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    Women’s Values and Preferences for Thromboprophylaxis during Pregnancy : A Comparison of Direct-choice and Decision Analysis using Patient Specific Utilities
    (2015) Eckman, Mark H.; Alonso-Coello, Pablo; Guyatt, Gordon H.; Ebrahim, Shanil; Tikkinen, Kari A.O.; Lopes, Luciane Cruz; Neumann Burotto, Gonzalo Ignacio; Mcdonald, Sarah D.; Zhang, Yuqing; Zhou, Qi; Akl, Elie A.; Jacobsen, Ann Flem; Santamaría, Amparo; Annichino-Bizzacchi, Joyce Maria; Bitar, Wael; Sandset, Per Morten; Bates, Shannon M.