Table 2 Heterogeneity assessments and sensitivity analysis

CRP (all cut-offs)

Predetermined cut-off

Studies using a predetermined cut-off had slightly lower accuracy

0.003

Gestational age range

Excluding studies that included GA < 24 weeks resulted in a slightly lower accuracy

Interval between sampling and delivery

Studies > 72 h had lower accuracy

< 0.001

Applicability concerns in patient selection domain

Excluding studies with high concerns did not change the SROC curve

Risk of bias in patient selection domain

Studies with low risk score had lower accuracy

< 0.001

Publication year after 2000

Excluding studies published before year 2000 yielded a slightly lower accuracy

Assay type

Studies with CRP assays after standardisation (year 1993) had lower accuracy

< 0.001

PCT

Predetermined cut-off

Studies using a predetermined cut-off had slightly lower accuracy

0.026

Gestational age range

Excluding studies that included GA < 24 had no effect

Interval between sampling and delivery

No difference

0.178

Applicability concerns in patient selection domain

Excluding studies with high concerns resulted in a much lower accuracy and a change in shape of the curve

Risk of bias in patient selection

Studies with low risk score had lower accuracy

< 0.001

Publication year after 2000

Not assessed as all studies were published after year 2000

IL6

Predetermined cut-off

Not assessed as 1 subgroup had < 2 studies

Gestational age range

Excluding studies that included GA < 24 weeks resulted in a slightly higher accuracy and change in shape of SROC curve

Interval between sampling and delivery

Studies ≤ 72 h had lower accuracy

< 0.001

Applicability concerns in patient selection domain

Not assessed as all studies had low applicability concerns

Risk of bias in patient selection

Not assessed as 1 subgroup had < 2 studies

Publication year after 2000

Not assessed as all studies were published after year 2000