Ventilator‐free days
Study	High PEEP	Low PEEP	P Value
Brower 2004	Means: 13.8	Means: 14.5	0,50
Brower 2004	SD: 10.6	SD: 10.4
Brower 2004	No. of patients: 276	No. of patients: 273
Mercat 2008	Median: 7	Median: 3	0,04
Mercat 2008	Interquartile range: 0.0‐19	Interquartile range: 0.0‐17
Mercat 2008	No. of patients: 385	No. of patients: 382
Talmor 2008	Median: 11.5	Median: 7	0,50
Talmor 2008	Interquartile range: 0.0‐20.3	Interquartile range: 0.0‐17
Talmor 2008	No. of patients: 30	No. of patients: 31
Villar 2006	Means: 10.9	Means: 6	0,008
Villar 2006	SD: 9.4	SD: 7.9
Villar 2006	No. of patients: 50	No. of patients: 45