A longstanding key concern with decompressive craniectomy is that any effect to increase survival is not necessarily accompanied by an increase in quality of life. That is, perceived benefit may in fact be a movement of a proportion of patients from death to survival with severe disability. This might be interpreted as a worsening of outcome. Severe disability survival has attendant costs to society, no obvious patient benefits and indeed possible patient harm through physical, psychological and emotional suffering. Yet, as Honeybul et al1 detail clearly, quality clinical trials which clearly define the treatment effect of decompressive craniectomy are lacking. Practical conclusions about the treatment effect of decompressive craniectomy on survival and quality of life for any one particular patient are often little more than guesswork or preconceived bias.

The limitations of our current evidence base are in part due to the broader issue of the heterogeneous nature of traumatic brain injury (TBI). As a disease, TBI has numerous differing pathophysiological processes which make it difficult to obtain evidence of efficacy …