Table 4

Risk factor reporting and adjustment

Number of studies reporting (n, %)Number of studies providing adjustment or stratification (n, %)
Patient age936 (95.0)145 (14.7)
Comorbidities402 (40.8)146 (14.8)
ASA status74 (7.5)33 (3.4)
Case urgency730 (74.1)693 (70.4)
HIV status45 (4.6)25 (2.5)
Clinical Risk Score331 (33.6)141 (14.3)
  • Reporting of case urgency required presentation of the proportion of planned versus emergent cases, or a population consisting exclusively of either planned or emergent cases. The latter group was considered to have reported mortality ‘stratified’ on urgency. ‘Adjustment or stratification’ implies a statistical analysis of the risk factor in relation to mortality, or mortality provided for separate strata.