![]() ![]() There are additional considerations for AD meta-analyses evaluating the effects of interventions on time-to-event outcomes, which are frequently based on hazard ratios (HRs), either derived directly from trial publications, or estimated indirectly from published statistics or from data extracted from Kaplan–Meier (KM) curves. Most standard reviews continue to rely on published AD, and if some eligible trials are unpublished, or reported trial analyses are based on a subset of participants or outcomes, then information may be limited, and AD meta-analyses will be at risk of reporting biases. It remains unclear when standard systematic reviews and meta-analyses of published aggregate data (AD) are reliable enough to form robust clinical conclusions, and consequently when the ‘gold standard’ individual participant data (IPD) approach might be required. LAS received no specific funding for the work.Ĭompeting interests: The authors have declared that no competing interests exist The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Note that the original IPD for the 238 trial/trial comparisons cannot be shared publicly because they are subject to individual data sharing agreements, and are not needed to replicate the analyses.įunding: JFT, DF, SB and MKBP were funded by the UK Medical Research Council (MC_UU_12023/24). This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.ĭata Availability: All aggregate data relevant to the analyses, whether derived from trial publications or from the original analyses of anonymised participant data (IPD) are within the manuscript and/or Supporting Information file. Received: Accepted: DecemPublished: January 31, 2020Ĭopyright: © 2020 Tierney et al. Shapiro, University of Pittsburgh, UNITED STATES PLoS Med 17(1):Īcademic Editor: Steven D. A lack of power at the meta-analysis level may have prevented us identifying additional factors associated with the reliability of AD meta-analyses, and we cannot be sure that our results are generalisable to all outcomes and effect measures.Ĭitation: Tierney JF, Fisher DJ, Burdett S, Stewart LA, Parmar MKB (2020) Comparison of aggregate and individual participant data approaches to meta-analysis of randomised trials: An observational study. We utilised the results to construct a decision tree for assessing whether an AD meta-analysis includes sufficient information, and when estimates of effects are most likely to be reliable. However, even when the information size of the AD was large, individual meta-analysis HRs could still differ from their IPD equivalents by a relative 10% in favour of the research intervention to 5% in favour of control. These limits tended to narrow with an increasing number ( p = 0.077) or proportion of events ( p = 0.11) in the AD. On average, meta-analysis HRs from published AD slightly tended to favour the research interventions whether based on fixed-effect (HR AD to HR IPD ratio = 0.97, p = 0.088) or random-effects (HR AD to HR IPD ratio = 0.96, p = 0.044) models, but the limits of agreement show that for individual meta-analyses, agreement was much more variable. These limits narrowed with an increasing number of participants ( p < 0.001) or a greater number ( p < 0.001) or proportion ( p < 0.001) of events in the AD. On average, trial HRs derived from published AD were slightly more in favour of the research interventions than those from IPD (HR AD to HR IPD ratio = 0.95, p = 0.007), but the limits of agreement show that for individual trials, the HRs could deviate substantially. A HR and SE could be generated for 127 trials, representing 53% of the trials and approximately 79% of eligible participants. The 18 systematic reviews comprised 238 unique trials or trial comparisons, including 37,082 participants. We assessed agreement, and whether this was associated with trial or meta-analysis characteristics, using the approach of Bland and Altman. We used paired t tests to assess whether HRs and SEs from published AD differed on average from those from IPD. We also extracted or estimated the number of events. ![]() We extracted or estimated hazard ratios (HRs) and standard errors (SEs) for survival from trial reports and compared these with IPD equivalents at both the trial and meta-analysis level. We used 18 cancer systematic reviews that included IPD meta-analyses: all of those completed and published by the Meta-analysis Group of the MRC Clinical Trials Unit from 1991 to 2010. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |