Table 2
Rates of visual field change corresponding to total change in mean deviation (MD) over 2, 3 and 5 years (a) and the number of visual fields per year required to detect the corresponding change with 80% power (b)
(a) Total MD change (dB)
Progression rate (dB/year)
2 years
3 years
5 years
−1.0
−0.5
−0.3
−0.2
−2.0
−1.0
−0.7
−0.4
−4.0
−2.0
−1.3
−0.8
(b) Total MD change (dB)
Annual examinations
2 years
3 years
5 years
−1.0
7
6
4
−2.0
5
4
3
−4.0
3
3
2