TABLE 2.

Patient Stratification and Proposed Analysis Paradigm to Evaluate Alternative (Ventilator-Associated Condition) Surveillance Definitions

Patient Population (Underlying Characteristics)	Clinical Criteria (Ventilation Parameter Settings)	Patient Outcomes (Evaluation Metrics)
Data source (i.e., Medical Information Mart for Intensive Care III or eICU Clinical Research Database)	Tier 1 of VAC criteria	Inhospital mortality
	Minimum FiO2	ICU LOS
	Minimum positive end-expiratory pressure
		Hospital LOS
Type of ICU (i.e., medical, surgical, and neuro	Calendar day vs 24-hr day
	Early vs late VAC (<7 vs ≥7 d)

eICU = electronic ICU, LOS = length of stay, VAC = ventilator-associated condition.

The levels of analysis triggering alternative VAC surveillance definitions (see clinical criteria) across patient subpopulations (based on data source and ICU type) are described. Further, three distinct outcomes were used to compare/contrast the performance of varying definitions.