Chaudhry 2000.

Methods	Single‐centre, uncertain number of surgeons, single‐masked RCT. Study dates not reported.
Participants	80 people with open‐angle glaucoma or CACG undergoing trabeculectomy for the first time on one eye. 29% were men, the mean age was 68 years, and 5 participants were black, the rest were white.
Interventions	Subconjunctival injections, of 5 mg 5‐FU, in the first 11 postoperative days (total of 3 injections). The control group did not receive placebo injections.
Outcomes	Proportion failed (IOP > 21 mm Hg without medication) at 1 year; mean IOP; complications and reduction in number of medications.
Notes	Main outcome measure stated as with or without medications but quoted as without only. Funding sources were not reported. The authors do not include a statement about declarations of interest.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	The authors informed us by personal communication that random number lists were used to determine randomisation. "Forty patients were randomised to the low‐dose 5‐fluorouracil group and received three subconjunctival injection of 5 mg each over 11 postoperative days after initial trabeculectomy. Forty patients were randomised to initial trabeculectomy without 5‐fluorouracil injections."
Allocation concealment (selection bias)	Low risk	The authors responded to enquiries to inform us that treatment group was allocated according to a predetermined random number list by a secretary that was unaware of the patient's identity. Randomisation occurred at the time of surgical scheduling.
Blinding (performance bias and detection bias) All outcomes	High risk	"The surgeon was masked as to the patient group." "Beyond the first visit after the surgery, the team was no longer masked as to which group the patients were in." Therefore, postoperative measurements of IOP were not blinded. No masking of patients.
Incomplete outcome data (attrition bias) All outcomes	High risk	"Of the 40 patients in each group, 38 completed the study. Two patients from each group failed to meet the postoperative treatment protocol criteria and were not included in the analysis." This implies per protocol as opposed to intention‐to‐treat analysis. Mean follow‐up reported for 5‐FU and non‐5‐FU group.
Selective reporting (reporting bias)	Low risk	Primary outcomes clearly stated in the statistical methods section and there was no statistically significant difference in these primary outcomes.