Höffling‐Lima 2001.

Methods	Parallel‐group RCT
Participants	40 participants with allergic conjunctivitis
Interventions	Two treatment arms: ketotifen 0.05%; olopatadine 0.1%. Duration of treatment 30 days
Outcomes	Participants' assessment of severity of ocular symptoms: itching, burning, watering, discharge, photophobia (4‐point scale; 0 = none, 3 = severe) Investigator assessment of ocular signs Time points: at days 1, 2, 7, 14, and 30 after treatment
Country	Brazil
Number randomised, gender (male:female)	40 participants randomised, 34 participants analysed. M:F 15:19
Age mean (SD), median, range	Mean (range) 27 years (5‐73)
Notes	Study conducted from 1 February to 30 June 1999. Source of funding not stated. The authors declared no commercial interest in the drugs evaluated and did not receive any direct or indirect benefit or financial support for this study
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation (p.416 ‐ methods): "A masked and randomised clinical study was conducted..." "the introduction of treatment was randomized beforehand..."
Allocation concealment (selection bias)	Unclear risk	The method used to conceal the allocation sequence was not described
Incomplete outcome data (attrition bias) All outcomes	Low risk	Data were nearly fully reported, with 15% lost to follow‐up, and reasons were given
Selective reporting (reporting bias)	Low risk	Evidence was available of proper outcome reporting
Other bias	Low risk	No apparent evidence of other risk of bias
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Masking of participants (p.416 ‐ methods): "A masked and randomised clinical study was conducted..." "... and bottles with topical medications were masked by ophthalmos laboratory."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Masking of investigator (p.417 ‐ methods): "only the medical monitors delivered the drugs to patients..."