New approaches to increase statistical power in TBI trials: insights from the IMPACT study
Faculty of Medicine and Health Sciences
Vienna :Springer-verlag wien
Acta neurochirurgica: supplementum. - Wien
5th Scientific Meeting of the Neurorehabilitation and Reconstructive, Neurosurgery Committee of the, World-Federation-of-Neurosurgical-Societies held in conjunction with the, 2nd Congress of the International-Society-of-Reconstructive-Neurosurgery, SEP 13-16, 2007, Taipei, TAIWAN
, p. 119-124
University of Antwerp
Introduction. None of the multi-centre phase III randomized controlled trials (RCTs) performed in TBI have convincingly demonstrated efficacy. Problems in clinical trial desing and analysis may have contributed to these failures. Clinical trials in the TBI population pose several complicated methodological challenges, related especially to the heterogencity within the IMPACT (International Mission on Prognosis and clinical Trial design in TBD databalse and investigate the application of conventional and innovative methods for the statistical analysis of trials in TBI. Mathods and results. Simulation studies in the IMPACT database (N=9205) showed substantial gains in efficiency with covariate adjustment. Adjusting for 7 important predicatiors yielded up to a 28% potential reduction i 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 optimising future TBI trials.