title: The authors reply.
authors.forename: Bradley D
authors.initials: BD
authors.lastname: Freeman
authors.forename: Peter E
authors.initials: PE
authors.lastname: Morris
mesh_terms: D003422:Critical Care / Q000379:methods*; D006801:Humans; D007362:Intensive Care Units / Q000458:organization & administration*; D012131:Respiratory Insufficiency / Q000628:therapy*; D014139:Tracheostomy / Q000379:methods* / Q000706:statistics & numerical data*