Table 1 Eligibility criteria

Types of study designs

Any of the following VAP prognostic studies (published or unpublished) with corresponding control groups (non-VAP patients/survivors):

Interventional study

RCT or clinical trial

Observational study

Prospective cohort study or prospective analysis

Retrospective cohort study or retrospective analysis

Nested case-control study

Case-control study with similar patient groups

Case-control study with unclear or non-equivalent controls.

Types of participants

Any of the following adult (15 years or older) ICU population requiring MV:

Cases: patients with VAP/non-survivor group/patients with clinical failure

Controls: patients without VAP/survivor groups/patients with successful treatment

Types of exposures

Any of the following exposures:

Host- or patient-related factors

Treatment- or intervention-related factors

Device-related factors

Personnel-related factors

Environmental-related factors

Others (time-dependent factors, any ICU adverse events)

Types of outcome measures

Primary outcome measure

Initial episode of microbiologically confirmed VAP (as defined by study authors)

Any of the following secondary outcome measures:

VAP as a predictor of ICU mortality (as reported by study authors)

ICU mortality associated with VAP (as reported by study authors)

ICU mortality associated with VAP in RCT studies

ICU mortality associated with VAP in matched studies

ICU mortality associated with clinically and microbiologically confirmed VAP

In-hospital mortality associated with VAP (as stated by study authors)

Duration of MV (time, measured in days, from initiation to discontinuation)

ICU LOS (time, measured in days, from admission to ICU discharge or death)

Hospital LOS (time, measured in days, from admission to hospital discharge or death)

Microbiological findings by VAP-associated microorganisms (microbiological profile)

Cost of antibiotic treatment of VAP (currency, in US dollar)

Hospitalization costs (currency, in US dollar)

Types of ICU settings

No restrictions imposed

Types of languages

No restrictions imposed

Timing

Any of the following study endpoints: time to VAP, removal of critical ill patients from MV or planned extubation.

No time restrictions for follow-up and retrospective analysis. However, patients must be intubated/ventilated for at least 48 hours.