Table 4

 Mean difference and 95% limits of agreement between GAT and other tonometric instruments—summary of findings from this and previous studies. Values (mm Hg) are given as means (95% CI); a positive mean difference indicates that Goldmann values are higher

StudyGAT interobserver differencesTono-PenOBFNCTNCT type
OBF, ocular blood flow; NCT, non-contact tonometer.
*Oculab Tono-Pen; **Mentor Tono-Pen XL; ***Bio-Rad Tono-Pen XL; OBF tonograph (OBF Labs).
†Overall value: tonometer overestimates GAT at low IOPs and underestimates at high IOPs.
‡Overall value: tonometer underestimates GAT at low IOPs and overestimates at high IOPs.
This study−0.4 (2.6)‡+0.6 (6.5)**+ 0.1 (5.4)‡+ 0.7 (4.8)‡Canon TX-10
Thorburn, 197814−0.7 (3.1)
Bandyopadhyay et al, 200215−1.0 (4.5)**
Iester et al, 200110+0.2 (6.3)**†
Bafa et al, 20019−0.6 (8.3)**−0.7 (7.7)
Midelfart and Wigers, 199426+2.4 (4.6)***
Geyer et al, 19925+3.9 (6.5)*
Frenkel et al, 198818+0.8 (6.1)*†
Minckler et al, 198727+1.7 (6.1)*
Kao et al, 198717−0.5 (7.4)*†
Gunvant et al, 200420−0.5 (6.3)‡
Yang et al, 20008+0.26 (4.6)†
Bhan et al, 200319−2.7 (6.6)‡
Jorge et al, 200321−0.1 (3.3)Reichert AT550
Jorge et al, 200212−0.1 (2.2) +0.9 (2.5)Reichert AT550 Reichert XpertP
Popovich and Shields, 19977+0.6 (4.5)Reichert XPERT
Hansen, 19956+0.9 (4.9)Reichert XPERT
Kretz and Demailly, 199223+0.1 (2.9)Reichert XPERT
Hollo et al, 199228−3.9 (5.7)Reichert XPERT
Myers et al, 199029−0.7 (5.3)Reichert XPERT
Parker et al, 200111−0.1 (2.2)−0.5 (2.2)Keeler Pulsair 3000
Mackie et al, 199622−1.0 (7.1)Keeler Pulsair 2000