Assem M Khamis1, Mohamad El Moheb2, Johny Nicolas2, Ghida Iskandarani2, Marwan M Refaat3, Elie A Akl4. 1. Clinical Research Institute, American University of Beirut Medical Center, Beirut, Lebanon. 2. Faculty of Medicine, American University of Beirut Medical Center, Beirut, Lebanon. 3. Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon. 4. Clinical Research Institute, American University of Beirut Medical Center, Beirut, Lebanon; Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon; Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada. Electronic address: ea32@aub.edu.lb.
Abstract
OBJECTIVE: The objective of this study was to assess and to investigate the reasons for the variations between the results of meta-analyses addressing the same question. STUDY DESIGN AND SETTING: We included systematic reviews, and the trials that they included, on the use of implantable cardiac defibrillator (ICD) in patients with nonischemic cardiomyopathy. We assessed the variation between meta-analyses pooled effect estimates by calculating the percentage of absolute difference. We developed a list of 10 reasons for variations between the results of the meta-analyses clustered in four overarching categories. RESULTS: We identified 21 systematic reviews including six trials and reporting on 22 eligible meta-analyses. The percentage of absolute difference between each of the 22 pooled effect estimates (included odds ratio, risk ratio, hazard ratio) and their median value had an average of 3.2%. The number of trials for which the following categories of reasons for variations applied were as follows: (1) different decision to include or exclude trials (n = 3); (2) differences in analytical approaches (n = 6); (3) errors in conducting meta-analyses (n = 5); and (4) unclear reason (n = 1). CONCLUSION: Few of the observed variations between the results of the 22 meta-analyses could lead clinicians or guideline development organizations to adopt different courses of actions. Variations were most frequently related to both errors and variations in trial eligibility and analytical approaches.
OBJECTIVE: The objective of this study was to assess and to investigate the reasons for the variations between the results of meta-analyses addressing the same question. STUDY DESIGN AND SETTING: We included systematic reviews, and the trials that they included, on the use of implantable cardiac defibrillator (ICD) in patients with nonischemic cardiomyopathy. We assessed the variation between meta-analyses pooled effect estimates by calculating the percentage of absolute difference. We developed a list of 10 reasons for variations between the results of the meta-analyses clustered in four overarching categories. RESULTS: We identified 21 systematic reviews including six trials and reporting on 22 eligible meta-analyses. The percentage of absolute difference between each of the 22 pooled effect estimates (included odds ratio, risk ratio, hazard ratio) and their median value had an average of 3.2%. The number of trials for which the following categories of reasons for variations applied were as follows: (1) different decision to include or exclude trials (n = 3); (2) differences in analytical approaches (n = 6); (3) errors in conducting meta-analyses (n = 5); and (4) unclear reason (n = 1). CONCLUSION: Few of the observed variations between the results of the 22 meta-analyses could lead clinicians or guideline development organizations to adopt different courses of actions. Variations were most frequently related to both errors and variations in trial eligibility and analytical approaches.
Authors: Tai Lim Kim; Gwang Hun Jeong; Jae Won Yang; Keum Hwa Lee; Andreas Kronbichler; Hans J van der Vliet; Giuseppe Grosso; Fabio Galvano; Dagfinn Aune; Jong Yeob Kim; Nicola Veronese; Brendon Stubbs; Marco Solmi; Ai Koyanagi; Sung Hwi Hong; Elena Dragioti; Eunyoung Cho; Leandro F M de Rezende; Edward L Giovannucci; Jae Il Shin; Gabriele Gamerith Journal: Adv Nutr Date: 2020-11-16 Impact factor: 8.701
Authors: Lara A Kahale; Assem M Khamis; Batoul Diab; Yaping Chang; Luciane Cruz Lopes; Arnav Agarwal; Ling Li; Reem A Mustafa; Serge Koujanian; Reem Waziry; Jason W Busse; Abeer Dakik; Lotty Hooft; Gordon H Guyatt; Rob J P M Scholten; Elie A Akl Journal: Clin Epidemiol Date: 2020-05-27 Impact factor: 4.790