Considerable debate has centered on the validity of results from the landmark Second National Spinal Cord Injury Study (NASCIS-II), which was published in 1990.
In NASCIS-II, 487 patients with acute TSCIs were randomized to an initial bolus of 30 mg/kg of methylprednisolone followed by an infusion of 5.4 mg/kg per h for 23 h versus either naloxone or placebo.
The primary analysis among the 487 patients enrolled within 12 h in NASCIS-II failed to demonstrate a significant neurological benefit in the 162 patients randomized to methylprednisolone. However, a secondary analysis of 65 of these patients who received methylprednisolone within 8 h of injury suggested that this subgroup experienced improved neurological recovery at 6 months.
Critics of NASCIS-II highlight the limited credibility of subgroup testing, the potential importance of losses to follow-up, the small magnitude of observed treatment effects, and the arbitrary nature of an 8-h threshold.