### Materials and Methods

### Patients and visual field data

### Rates of visual field decay and modified glaucoma hemifield test clusters

*y = e*, that is,

^{a + bx}*log*. The rate of change was represented by the coefficient

_{e}y = a + bx*b*, which is the average annual rate of change in

*log*. The quantity

_{e}y*e*is interpreted as the residual y at each time interval. The rate of decay is defined as (

^{b}*1 - e*). To facilitate clinical understanding of the magnitude of the rates, the rates of decay derived from exponential regression were converted into %/year deterioration rates, where rate of decay (%/year) = (

^{b}*1-e*)(100). Thus, we measured the proportion of loss of visual sensitivity remaining.

^{b}*p*-value for the difference in rates. For each partition, we computed a

*t*-test statistic, and the corresponding

*p*-values were adjusted for multiple testing. The Benjamini-Hochberg correction was used to find the optimal

*p*-value to maximize the difference between the fast and slow component subgroups [10]. Each subgroup consisted of at least five test locations. The rate of decay (%/year) was also determined for the visual field series of each eye by taking the mean individual decay rates for each of the 52 test locations analyzed. The fast and slow components are the means of the rates for all points in each of these clusters.

### Estimation of spatial concordance

#### 1) Calculation of concordance ratio

#### 2) Calculation of average rates of decay in modified glaucoma hemifield test clusters

*R*[11].

### Results

### Patients and visual field data

### Evaluation of spatial concordance of visual field deterioration

#### 1) Concordance ratio

*p*= 0.049).

#### 2) Average rates of decay in the modified glaucoma hemifield test clusters

*p*< 0.05 in the concordant clusters of both eyes. Table 2 compares the frequency of belonging to the fast component for individual test locations and worsening frequency in modified GHT clusters. The mean number of deteriorating clusters and patients with bilateral deterioration increased significantly as the disease severity increased as categorized based on the baseline MD. The diagram on the right side of Fig. 3 shows the frequency distribution for cluster worsening across the visual field (defined as average rate of decay ≥10%/year for a cluster). The number of deteriorating clusters for the superior and inferior hemifields was 298 (59.4%) and 204 (40.6%), respectively (

*p*= 0.035).

### Discussion

*p*< 0.05). Concordant bilateral deterioration may merely reflect widespread glaucomatous deterioration, as those with concordant worsening had a higher number of clusters with deterioration compared to those with non-concordant bilateral deterioration. These worsening defects were evenly distributed between the modified GHT clusters. This suggests that visual field algorithms cannot assume that the region of deterioration in one eye would accurately predict the topography of early deterioration in the fellow eye.