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New approaches to increase statistical power in TBI trials: Insights from the IMPACT study

  • Conference paper
Reconstructive Neurosurgery

Part of the book series: Acta Neurochirurgica Supplementum ((NEUROCHIRURGICA,volume 101))

Abstract

Introduction. None of the multi-centre phase III randomized controlled trials (RCTs) performed in TBI have convincingly demonstrated efficacy. Problems in clinical trial design and analysis may have contributed to these failures. Clinical trials in the TBI population pose several complicated methodological challenges, related especially to the heterogeneity of the population. In this paper we examine the issue of heterogeneity within the IMPACT (International Mission on Prognosis and Clinical Trial design in TBI) database and investigate the application of conven tional and innovative methods for the statistical analysis of trials in TBI. Methods and results. Simulation studies in the IMPACT database (TV = 9205) showed substantial gains in efficiency with covariate adjustment. Adjusting for 7 important predictors yielded up to a 28% potential reduction in trial size. Ongoing analyses on the potential benefit of ordinal analysis, such as proportional odds and sliding dichotomy, gave promising results with even larger potential reductions in trial size. Conclusion. The statistical power of RCTs in TBI can be considerably increased by applying covariate adjustment and by ordinal analysis methods of the GOS. These methods need to be considered for optimizing future TBI trials.

The IMPACT Study Group is a collaborative venture including the division of Community Health Sciences, University of Edinburgh Scotland, The Department of Neurosurgeru Virginia Commonwealth University, Richmond, USA, The Center for Medical Decision Sciences, Department of Public Health, Erasmus MC, Rotterdam, The Netherlands and University Hospital Antwerp, Belgium.

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Author information

Authors and Affiliations

  1. Department of Neurosurgery, University Hospital Antwerp, Wilrijkstraat 10, 2650, Edegem, Belgium

    Andrew I. R. Maas

  2. Center for Medical Decision Sciences, Department of Public Health, Erasmus MC, Rotterdam, The Netherlands

    Andrew I. R. Maas & H. F. Lingsma

Authors
  1. Andrew I. R. Maas
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  2. H. F. Lingsma
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IMPACT study group

Editor information

Editors and Affiliations

  1. Department of Neurosurgery, Municipal Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan, R.O.C.

    Wen-Ta Chiu

  2. Department of Neurosurgery, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan, R.O.C.

    Yung-Hsiao Chiang

  3. Department of Neurosurgery, National Taiwan University Hospital, National Taiwan University, Taipei, Taiwan, R.O.C.

    Ming-Chien Kao  & Ching-Chang Hung  & 

  4. Center for Neuropsychiatry, China Medical University Hospital, China Medical University, Taichung, Taiwan, R.O.C.

    Shinn-Zong Lin

  5. Department of Neurosurgery, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan, R.O.C.

    Han-Jung Chen

  6. Department of Rehabilitation Medicine, Chang Gung Memorial Hospital, Chang Gung University, Taipei, Taiwan, R.O.C.

    Simon F. T. Tang

  7. National Institute on Drug Abuse, National Institute of Health, Baltimore, USA

    Barry J. Hoffer

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© 2008 Springer-Verlag

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Maas, A.I.R., Lingsma, H.F., IMPACT study group. (2008). New approaches to increase statistical power in TBI trials: Insights from the IMPACT study. In: Chiu, WT., et al. Reconstructive Neurosurgery. Acta Neurochirurgica Supplementum, vol 101. Springer, Vienna. https://doi.org/10.1007/978-3-211-78205-7_20

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  • DOI: https://doi.org/10.1007/978-3-211-78205-7_20

  • Publisher Name: Springer, Vienna

  • Print ISBN: 978-3-211-78204-0

  • Online ISBN: 978-3-211-78205-7

  • eBook Packages: MedicineMedicine (R0)

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