SDH was reported in 4.5% of the patients in the review , which is in the same range as in our study (3.7%). However, our figure shows only those requiring surgical treatment, and the total number of SDH is probably higher. The infection rate of 6.4% is higher than in many other studies (average 3%, but ranging from 0 to 10%) . Similarly, the operation-related mortality of 0.5% is somewhat higher than in contemporary studies. This was calculated in the cited review to be 0.2%, for the years 2006–2010, with a range between 0 and 0.8%, for the 13 studies reporting numbers on shunt surgery-related mortality . Again, the unselected patient material in the SHQR compared with the less extensive single-center studies with stricter inclusion criteria reviewed by Toma et al.  may have influenced the results.