Datasets currently included in IMPACT I

Unselected Prospective series published in past decade
N Study Years Publication plus year
TCDB 746 1984-1987 Foulkes et al. 1991
EBIC core data study* 847 1995 Murray et al. 1999
UK 4 988 1986-1988 Murray et al. 1999
Total: 2581
Therapeutic trials published or conducted in past decade (N>300)
N Study Years Publication plus year
HIT I Nimodipine 351 1987-1989 Bailey et al. 1991
HIT II Nimodipine 852 1989-1991 EUR Study Group 1994
Tirilazad trials (2)* 2269 1991-1994 Marshall et al. 1998
Saphir 924 1995-1997 -
International Selfotel trial 409 1994-1996 Morris et al. 1999
PEGSOD 1574 1993-1995 Young et al. 1996**
SKB 139 1996 Marmarou et al. 1999
Total: 6518

Datasets added in IMPACT II
(APOE, NABIS hypothermia, Cerestat, Pharmos dexanabinol)
N Description
Teasdale et al. 2005
351 This cohort study investigated the relation between ApoE genotype and outcome across all injury severities, includes many patients with mild injuries, accurate details on treatment and 8-point GOSE.

NABIS hypothermia
Clifton et al. 2001
392 We had originally planned to include this dataset in the current grant period, but received the full dataset too late to include in IMPACT I. Considerable center effects and variations in patient management have been reported for this dataset.

532 Is an unpublished RCT investigating the effect of Aptiganel HCl, a non competitive NMDA blocker in severe TBI.

The Pharmos Dexanabiol Trial
Maas et al. 2006
861 Investigated safety and efficacy of dexanabinol, and is the most recent conventional Phase III trial in TBI. Dexanabinol is a non-psychotropic cannibinoid agonist with demonstrated neuroprotection in preclinical studies. Both the Principal Investigator and Professor Gordon Murray are well acquainted with this study as they have been closely involved in the design and analysis of the trial (Maas et al 2006). The Pharmos study includes extensive data on patient management and outcome assessed by the 8 -point GOSE together with Quality of Life scores (SF 36 and CIQ).

Datasets in collaboration with CRASH & TARN investigators
N Description
Edwards et al. 2005
Roberts et al. 2004
10008 Aimed to resolve the uncertainty concerning the use of steroids in TBI and represents the only mega trial conducted in the field of TBI. The dataset is typical of a mega trial with large numbers, limited information and simple outcome assessment. The CRASH investigators recruited 10008 patients in 239 centers from 49 countries. We greatly appreciate the permission granted by the CRASH management group to provide us with the raw data and consider it especially relevant to include this study in the IMPACT dataset because it contains a large number of patients with mild injury and allows us to evaluate the relative merits of a mega trial based on actual data rather than simulations studies.

1989- ongoing
Patel et al. 2005
22000 TARN represents a large dataset of the Trauma Audit and Research Network, and includes over 22000 patients with TBI. Although it is not a clinical trial, the methodology of data collection (large numbers, simple data) is very similar to that which would be applied in a mega trial. We therefore consider it an asset to include the TARN data on TBI within our analysis, particularly in specific aim 4.

* These studies also included patients with moderate head injury. The number of patients with severe TBI in the EBIC Core data study was: 551 and in the Tirilazad trials: 1783.

** Publication refers to first trial.