Pointwise linear regression analysis was performed to estimate the rate of change of visual sensitivity in the 54 test locations. Using the conservative criteria to define progression (at least three adjacent nonedge (except for the two nasal edge points) locations with a rate of change of visual sensitivity of ≤−1 dB/y), there were 11 (6.1%), 7 (3.9%), and 6 (3.4%) eyes detected with progression by Matrix FDTP, SAP, and SAP (transformed), respectively (
Fig. 2A). With the moderate criteria (any three locations with ≤−1 dB/y for nonedge and ≤−2 dB/y for edge locations), there were 26 (14.5%), 10 (5.6%), and 13 (7.3%) eyes that progressed, respectively (
Fig. 2B). With the liberal criteria (any two locations with ≤−1 dB/y for nonedge and ≤−2 dB/y for edge locations), 36 (20.1%), 21 (11.7%), and 24 (13.4%) eyes progressed, respectively (
Fig. 2C). Matrix FDTP detected significantly more progressing eyes than SAP using the liberal and moderate criteria (
P ≤ 0.042). Likewise, the survival probability of Matrix FDTP for detection of progression was significantly worse compared to SAP (
P ≤ 0.042) and SAP (transformed) (
P ≤ 0.005) using the liberal and the moderate criteria (
Fig. 3). The agreement of progression detection between Matrix FDTP and SAP, and between Matrix FDTP and SAP (transformed) was poor to fair (
κ ranged between 0.066 and 0.403) independent of the criteria of progression. In the normal group, Matrix FDTP detected two progressing eyes using the liberal criteria. No eyes showed progression in Matrix FDTP/SAP using the conservative and the moderate criteria.
Taking all the 54 test locations into consideration (a total of 54 × 179 = 9666 locations) and defining a location as progressing when its rate of change was ≤−1 dB/y for nonedge and ≤−2 dB/y for edge locations (
P < 0.05), Matrix FDTP detected a total of 176 progressing locations in the glaucoma group, which was significantly greater than SAP (103,
P < 0.001), and SAP (transformed) (124,
P = 0.003,
Fig. 4). There were no significant differences in the number of significant improvement (≥1 dB/y for nonedge locations and ≥2 dB/y for edge locations) between Matrix FDTP (
n = 5) and SAP (
n = 10,
P = 0.804), and between Matrix FDTP and SAP (transformed) (
n = 14,
P = 0.848,
Fig. 5). This frequency distribution of the rates of change of visual sensitivity of individual locations of Matrix FDTP, SAP, and SAP (transformed) are shown in
Figure 6.
Figure 7 shows the spatial distribution of the progressing locations detected by Matrix FDTP and SAP for individual eyes. The spatial agreement of progression detection between the two perimetric tests was poor.