Table 1

Publication characteristics

Quality score
 6–12 (poor)5185
 13–18 (average)813
 19–26 (good)12
 Median (±SD)8 (±2.9)
Patient enrolment
Study design
 Single centre4982
Type of study
  Randomised controlled trial11.7
 Observational studies5998
Outcome assessment
 Independent clinical outcome assessment35
 Modified Rankin Scale915
 Glasgow Outcome Scale3355
 Loss of follow-up reported1118
Time of outcome assessment
 Short term (‘discharge’ to 1 month)1118
 Mid term (>1 month to 1 year postop)2338
 Long term (>1 year postop)35
 Patient years’ follow-up1118
 No information on time of outcome measurement1220
  • EGFP, Excellent, Good, Fair, Poor.