| Table 1: Prevalence of increased intraocular pressure (IOP) and glaucomatous visual field defects | |||||
| Study and location | Age range of subjects, yr | IOP, mm Hg | Prevalence of increased IOP, % | % of subjects with visual field defects | Ratio of field defect to increased IOP |
| Hollows et al, [44] Ferndale, Wales | 40-74 | > 20 | 9.4 | 0.31 | 1:30 |
| Bengtsson, [45] Dalby, Sweden | 55-70 | > 20.5 | 7.3 | 0.33 | 1:22 |
| Liebowitz et al, [46] Framingham, Mass. | 52-85 | > 21 | 7.6 | 0.36 | 1:21 |
| Stromberg, [47] Skovde, Sweden | > 40 | > 21 | 4.5 | 0.36 | 1:12 |