Table 2.

Study definitions

Eligible inpatient wards	Areas where care is provided to patients who are admitted to the hospital, other than the PICU, NICU, operating rooms and other designated areas where anesthetist-supervised procedures are performed
	Admitted patients cared for in emergency departments will be regarded as in an eligible ‘ward’ if the documentation format is the same in the emergency department as in the inpatient ward. If the emergency department continues to use a separate ‘emergency department’ documentation record for admitted patients then the emergency department will be deemed an ineligible area
PICU	A PICU is defined as a designated staffed area for prolonged mechanical ventilation, invasive monitoring and circulatory support for children, including but not limited to neonates. Other areas designated for patients of increased acuity, such as ‘constant observation’ or ‘high dependency’ or ‘step-down’ units, will be regarded as part of the PICU where the PICU staff physicians are wholly or jointly responsible for the care of children in these areas (can write orders in the chart). Routinely admitted patients will include children beyond the neonatal period who are <12 years of age at admission
MET-RRT	An MET-RRT is defined as an identified team of one or more trained healthcare professionals who report to an on-service PICU physician and perform urgent consultations on hospital inpatients. An MET-RRT ‘call’ is analogous to an ICU consultation in hospitals without an MET-RRT. As the effectors of expertise, the impact of the MET-RRT (or other ICU team) is dependent upon appropriate identification of patients at risk and timely referral
Urgent PICU admission	An admission to the PICU with departure from the event location in <6 h from the time the PICU admission was initiated. Initiation is the time when the PICU admission is confirmed, or confirmed as a ‘definite possibility following surgery’ in cases where post-operative care in the PICU might be required. PICU admissions initiated in the OR are also regarded as urgent ICU admissions, irrespective of the time between initiation and departure from the OR
Time of transfer	Transfer is when a patient is transferred urgently to a pediatric intensive care unit (PICU) in the participating hospital. The time of transfer is the arrival in the PICU. When a patient is admitted urgently from an eligible hospital ward to a PICU via a procedure in the OR, the time of transfer to the ‘PICU’ is regarded as beginning at the time of departure from the inpatient ward to the operating room. Treatments other than cardiopulmonary resuscitation provided in the operating room are not included in the calculation of the clinical deterioration event. Unexpected events occurring in the operating room that require postoperative/post-anesthetic care in the PICU, in patients who were not anticipated to require PICU at the time the patient was transferred from the inpatient ward to the operating room, will not be regarded as clinical deterioration events
Study Day	Study days are calendar days; they begin at 00:00:00 and end at 23:59:59
Study weeks	begin on Monday and end on Sunday. The first week of the study is study week 01