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
| Study | GAT interobserver differences | Tono-Pen | OBF | NCT | NCT type |
| 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 |
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.