Table 2.

Risk of bias assessment for the included studies[32]

Study	Participation	Attrition	Prognostic factor (Risk factors)	Outcome measurement (IAH/ACS)	Confounding	Analysis
Balogh et al., 2003 [16]	Partly	Unsure	Yes	Partly	Unsure	Yes
Balogh et al., 2011 [17]	Partly	Unsure	No	Partly	Unsure	Partly
Reintam Blaser et al., 2011 [15]	Yes	Unsure	Yes	Yes	Unsure	Yes
Dalfino et al., 2008 [9]	Yes	Unsure	No	Yes	Partly	Yes
De Keuleaner et al., 2011 [18]	Yes	Unsure	Yes	Partly	Unsure	Yes
Davis et al., 2013 [22]	Yes	Unsure	Partly	No	Unsure	Yes
Ke et al., 2012 [10]	Yes	Unsure	No	Yes	Partly	Yes
Kim et al., 2012 [19]	Yes	Unsure	Yes	Yes	Unsure	Yes
Madigan et al., 2008 [20]	Yes	Unsure	No	No	Partly	Yes
Malbrain et al., 2004 [1]	Yes	N/A – cross-sectional	Partly	Yes	Unsure	Yes
Malbrain et al., 2005 [24]	Yes	Unsure	Yes	Yes	Partly	Yes
McNelis et al., 2002 [21]	Yes	Unsure	No	Yes	Unsure	Yes
Neal et al., 2012 [23]	Partly	Unsure	Yes	No	Yes	Yes
Vidal et al., 2008 [2]	Yes	Unsure	No	Yes	Unsure	Yes

Where participation was defined as the study sample being representative of the patient population of interest, attrition was defined as loss to follow-up being described and not associated with key participant characteristics (that is, selection bias), prognostic factor indicated that risk factors were adequately defined and measured within the text of the paper (the authors of any studies not satisfying this criteria completely were contacted for definition clarification), outcome measurement indicated that intra-abdominal hypertension/abdominal compartment syndrome (IAH/ACS) is defined and adequately measured (for this category, 'yes’ specifically indicated that the WSACS consensus definitions and guidelines for intra-abdominal pressure (IAP) measurement were used by the studies whereas 'partly’ indicated IAH/ACS that the study used either the WSACS consensus definitions or IAP measurement guidelines (but not both), and 'no’ indicated that either the WSACS consensus definitions or measurement guidelines were both not used, or that some patients had their IAH or ACS diagnosed by physical examination) [42], confounding indicated that potential confounders were appropriately accounted for, and analysis indicated the statistical analysis is appropriate for the study design. In general, for each of the above categories, 'yes’ indicated conditions were satisfied, 'no’ indicated conditions were not satisfied, 'partly’ indicated conditions were partly satisfied, and 'unsure’ indicated it was unclear whether or not conditions were satisfied.