Thirteen RCTs were included in the review (n=2,222 patients). Sample sizes of included trials ranged from 21 patients in a cross-over design to 595 patients in a parallel design trial. Trial quality was generally moderate to good: Jadad scores ranged from 5 to 7 out of 8. There was no evidence of statistical heterogeneity in any of the analyses; fixed-effect and random-effects meta-analyses showed the same results. There was no evidence of publication bias based on a visual inspection of funnel plots.
Latanoprost (0.005% solution) versus travoprost (0.004% solution): There was a statistically significant reduction in the incidence of conjunctival hyperaemia in the latanoprost patients compared with the travoprost patients (OR 0.51, 95% CI 0.39 to 0.67; six trials, n=1,118 patients).
Latanoprost (0.005% solution) versus bimatoprost (0.003% solution): There was a statistically significant reduction in the incidence of conjunctival hyperaemia in the latanoprost patients compared with the bimatoprost patients (OR 0.32, 95% CI 0.24 to 0.42; eight trials, n=1,240 patients).
Sensitivity analyses indicated that the results were robust to removal of single trials; removal of any trial did not change the statistical significance of the results for either comparison.