Journal Club Summary

Methodology Score: 4/5                 
Usefulness Score: 4/5
Goyal M, Demchuk AM, Menon BK, et al.
N Engl J Med. 2015 Mar 12;372(11):1019-30
This multi-centre open label RCT compared endovascular treatment +/- tPA vs. standard therapy for a specific sub-group of patients with acute ischemic stroke who had a proximal artery occlusion and evidence of a small infarcted core with a larger at risk area of brain. Endovascular treatment improved outcomes, with NNT of 4 for independence at 90 days. This adds to the growing body of literature suggesting endovascular treatment is beneficial for carefully selected stroke patients. 
By: Dr. Sebastian Dewhirst
(Presented May 2015)

Epi lesson:

Number Needed to Treat (NNT)  
The NNT concept was created by Canadian Clinical Epidemiologist Dr Andreas Laupacis in 1988 to quantify the benefit of a new intervention.  NNT is the average number of patients who need to be treated to prevent one additional bad outcome (e.g. the number of patients that need to be treated for one to benefit compared with a control in a clinical trial). It is easily calculated as the inverse of the absolute risk reduction (1/ARR). The higher the NNT the less effective the treatment. 
An Assessment of Clinically Useful Measures of the Consequences of Treatment


By: Dr. Ian Stiell