Fig. 1
figure 1

The European Glaucoma Prevention Study (EGPS) showed that treatment of ocular hypertension with dorzolamide treatment alone did not significantly reduce intraocular pressure or progression to primary open angle glaucoma when compared to treatment with placebo. This result can be explained by the study design, regression to the mean at 6 months in both arms of the study and selective loss to follow-up of participants with higher intraocular pressures. IOP intraocular pressure, POAG primary open angle glaucoma and CI confidence interval.