Figure 3. Bland-Altman plots with subgroup analysis. The eyes with an average intraocular pressure (IOP) of >15.8 mmHg are compared to those with an average IOP of <15.8 mmHg. The differences between the two devices are plotted against the mean value of both for each subgroup. The upper and lower lines represent the 95% limits of agreement. Non-contact tonometer (NCT), Goldmann applanation tonometer (GAT), Goldmann-correlated IOP (IOPg), corneal compensated IOP (IOPcc).