Table 1.

Variables studied

Variable	Data format
Demographic/anamnestic variables
Age	Years (continuous)
Gender	Male/female (binary)
Admission type	Surgical/medical (binary)
Hospital length of stay prior to ICU admission	Days (continuous)
Comorbidity variables
Metastatic cancer	Yes/no (binary)
Haematological malignancy	Yes/no (binary)
AIDS	Yes/no (binary)
Physiological variables
Lowest heart rate*	Beats per minute (continuous)
Highest heart rate*	Beats per minute (continuous)
Lowest systolic blood pressure*	mm Hg (continuous)
Highest systolic blood pressure*	mm Hg (continuous)
Body temperature ≥39° C*	Yes/no (binary)
Biochemical variables
Lowest white cell count*	109/L (continuous)
Highest white cell count*	109/L (continuous)
Lowest potassium*	mmol/L (continuous)
Highest potassium*	mmol/L (continuous)
Lowest sodium*	mmol/L (continuous)
Highest sodium*	mmol/L (continuous)
Lowest bicarbonate*	mmol/L (continuous)
Treatment variables
Use of vasopressors/inotropes†	Yes/no (binary)
Use of mechanical ventilation†	Yes/no (binary)
Use of renal replacement therapy†	Yes/no (binary)
Outcome variable
Vital status 90 days after inclusion	Dead/alive (binary)

For detailed definitions of the variables, please refer to the original publications/protocols.^{8–10 22–24}

All variables registered at inclusion in the different studies/trials except where otherwise noted.

*Worst value registered during the 24 hours prior to inclusion (6S, TRISS, CLASSIC and SUP-ICU trials) or during the first 24 hours in the ICU (SUP-ICU and AID-ICU inception cohorts).

†Treatment initiated or continued on the day of inclusion.

6S, Scandinavian Starch for Severe Sepsis/Septic Shock; AID-ICU, Agents Intervening against Delirium in Intensive Care Unit; ICU, intensive care unit; CLASSIC, Conservative versus Liberal Approach to fluid therapy of Septic Shock in Intensive Care; SUP-ICU, Stress Ulcer Prophylaxis in the Intensive Care Unit; TRISS, Transfusion Requirements In Septic Shock.