Table 3.

Quality assessment of included observational studies using the modified Newcastle–Ottawa scale

Selection	Representativeness of the exposed cohort	This item will be assigned a ‘⋆’ when all eligible patients with severe sepsis or septic shock are included in the analysis during the study period
	Selection of the non-exposed cohort	This item will be assigned a ‘⋆’ when all eligible patients without aPC treatment are included in the analysis during the study period
	Ascertainment of exposure	This item will be assigned a ‘⋆’ when aPC administration is directly obtained from a medical chart, not from reporting by the patient
	Outcome of interest is not present at the start of the study	This item will be assigned a ‘⋆’ when the subject is alive at the time of enrolment
Comparability	Comparability of cohorts on the basis of design or analysis	Baseline characteristics of aPC and control groups are comparable. Usually this can be found in table 1 of the original article.
Outcome	Assessment of outcome	This item will be assigned a ‘⋆’when mortality is assessed by the investigator, not by the report of the patient's family or next-of-kin
	Is follow-up long enough for outcome to occur?	Adequate follow-up is carried out during hospital stay, ICU stay or redefined study time
	Adequacy of follow-up of the cohort	This item will be assigned a ‘⋆’ when the follow-up rate is >80%

aPC, activated protein C.