Forbes 1972.

Methods	Single‐centre double‐blind RCT.
Participants	28 individuals with haemophilia (20 haemophilia A, 8 haemophilia B; 15 severe, 11 moderate, 2 mild) Age: range 13 ‐ 65 years. 32 separate episodes of dental extractions.
Interventions	Tranexamic acid 1 g 3‐times‐a‐day, starting 2 hours before dental extractions, for 5 days. Placebo tablets given with the same schedule. Both interventions in association with IV factor VIII or IX equivalent of 1000 ml of human plasma 1 hour before extraction and, in the case of excessive bleeding, further administrations sufficient to stop bleeding.
Outcomes	Efficacy outcomes: Blood loss measured with 51Cr‐labelled red cells in oral secretions and faeces over 24‐hr collections for 5 days. Need for further replacement therapy after the initial dose. Safety: renal and liver function tests, electrocardiogram, adverse events.
Notes	Significant increase in ESR and fibrinogen levels in the placebo group were recorded, reflecting the amount of plasma or concentrate infused. Significant depression of urokinase sensitivity after treatment with tranexamic acid was shown.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Random allocation is stated. No further details given.
Allocation concealment (selection bias)	Unclear risk	Double‐blind technique and random allocation are stated. No further details given.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Both participants and clinicians did not know which tablet was given.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	The clinician did not know the treatment type and the results of laboratory assays.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No trial withdrawal or incomplete outcome data stated.
Selective reporting (reporting bias)	Low risk	Outcome data reported in the methods and results sections correspond.
Other bias	Low risk	No difference in haemophilia severity, mean level of plasma factor VIII/IX and the number of roots extracted in the 2 groups.