Table 2

Key predictor and outcome variables

VariableSourceVariable type
Outcome variablesPresence of severe ASE in each domain of EMS careChart reviewBinary
Preventability of ASEChart reviewCategorical
Patient-level explanatory variablesPatient ageChart reviewCategorical
Patient sexChart reviewCategorical
Witnessed arrestChart reviewBinary
Bystander CPRChart reviewBinary
Presenting rhythmChart reviewCategorical
EMS response timeChart reviewContinuous
EMS scene timeChart reviewContinuous
Study siteChart reviewCategorical
Organisation-level explanatory variablesNumber of ALS-trained providers on scene for OHCA responseAgency surveyContinuous
Number of total providers on scene for OHCA responseAgency surveyContinuous
Information resources availableAgency surveyCategorical
Response modelAgency surveyCategorical
Number of hours of annual paediatric training requiredAgency surveyContinuous
Level of training of paediatric care championAgency surveyCategorical
Annual paediatric volume of ‘lights and sirens’ callsAgency surveyContinuous
  • .ALS, advanced life support; ASE, adverse safety event; CPR, cardiopulmonary resuscitation; EMS, emergency medical services; OHCA, out-of-hospital cardiac arrest.