Effectiveness and safety of antifibrinolytic agents in the management of pulmonary haemorrhage: A systematic review with narrative synthesis

Table 2 Simplified GRADE-informed certainty of evidence for main outcomes

Outcome	Population/setting	Certainty	Main reasons for rating
Bleeding cessation	Stable non-massive adult haemoptysis, nebulised TXA	Low	Two consistent randomised trials; downgraded for imprecision (small samples)
Mortality	ICU/mixed-acuity adult haemoptysis	Very low	Directly conflicting observational signals; serious risk of bias from confounding by indication; downgraded for inconsistency and risk of bias
Recurrence	Stable non-massive adult and CF haemoptysis	Low	Sparse data from one trial and one uncontrolled pathway study; downgraded for imprecision and indirectness
Need for invasive procedures	Stable non-massive adult haemoptysis, nebulised TXA	Low	Consistent direction across two randomised trials and observational data; downgraded for imprecision
Length of stay	Stable non-massive adult haemoptysis, nebulised TXA	Low	Consistent direction across trial and observational data; downgraded for imprecision and indirectness across settings
Adverse events (thromboembolism, bronchospasm)	All settings	Very low	Most studies not designed or powered to detect these events; inconsistent or absent reporting; serious risk of bias and imprecision
Bleeding cessation, safety, and feasibility	ICU, paediatric, and ECMO populations	Very low	Small, retrospective, uncontrolled studies with serious risk of bias and indirectness; downgraded on all major domains

Certainty ratings are based on a simplified application of GRADE domains (risk of bias, inconsistency, indirectness, imprecision, publication bias) rather than a full formal GRADE assessment with separate domain scoring. CF: Cystic fibrosis; ECMO: Extracorporeal membrane oxygenation; ICU: Intensive care unit; TXA: Tranexamic acid.