Table 1. Diagnostic criteria for POAG.

Diagnostic test	Criteria
Visual field
++	At least two abnormal visual field tests by Humphrey automated perimetry, as defined by computer-based objective criteria, i.e., positive results of hemimeridional analyses of threshold tests (C24-2 or C30-2 full-threshold program) and/or the presence of one or more absolute defects in the central 30 degrees (as tested with the C64 suprathreshold program; 3-zone strategy), with ophthalmologic interpretation as definite or suspect glaucomatous field loss
+	Less than two abnormal visual field tests or an inability to perform reliable automated perimetry (because of severe visual impairment or infirmity), with ophthalmologic interpretation as definite glaucomatous field loss
Optic disc
++	At least two signs of optic disc damage present in fundus photographs and/or the ophthalmologic evaluation, including either a horizontal or vertical cup-disc ratio ≥0.7, narrowest remaining neuroretinal rim ≤0.1 disc diameters, notching, asymmetry in cup–disc ratios between eyes >0.2, or disc hemorrhages
+	Less than two signs of optic disc damage as described above (or unavailable photographs), with an ophthalmologic assessment or clinical record documenting definite glaucomatous optic nerve damage
Ophthalmologic examination
++	Clinical diagnosis of definite POAG after examination by the study ophthalmologist to exclude other possible causes for disc and field changes
+	Previous POAG history and treatment and/or visual field and disc damage, although a definite POAG diagnosis was not made at the time of the BFSG visit (e.g., because of inconclusive or incomplete data); the study ophthalmologist confirmed the diagnosis through record review or rE-examination

++, most complete classification data; +, less complete but sufficient for classification.

Those with POAG had a minimum of at least one plus (+) sign in each of the three categories.