Systematic Review of the Agreement of Tonometers with Goldmann Applanation Tonometry

Objective To assess the agreement of tonometers available for clinical practice with the Goldmann applanation tonometer (GAT), the most commonly accepted reference device. Design A systematic review and meta-analysis of directly comparative studies assessing the agreement of 1 or more tonometers with the reference tonometer (GAT). Participants A total of 11 582 participants (15 525 eyes) were included. Methods Summary 95% limits of agreement (LoA) were produced for each comparison. Main Outcome Measures Agreement, recordability, and reliability. Results A total of 102 studies, including 130 paired comparisons, were included, representing 8 tonometers: dynamic contour tonometer, noncontact tonometer (NCT), ocular response analyzer, Ocuton S, handheld applanation tonometer (HAT), rebound tonometer, transpalpebral tonometer, and Tono-Pen. The agreement (95% limits) seemed to vary across tonometers: 0.2 mmHg (−3.8 to 4.3 mmHg) for the NCT to 2.7 mmHg (−4.1 to 9.6 mmHg) for the Ocuton S. The estimated proportion within 2 mmHg of the GAT ranged from 33% (Ocuton S) to 66% and 59% (NCT and HAT, respectively). Substantial inter- and intraobserver variability were observed for all tonometers. Conclusions The NCT and HAT seem to achieve a measurement closest to the GAT. However, there was substantial variability in measurements both within and between studies. Financial Disclosure(s) The author(s) have no proprietary or commercial interest in any materials discussed in this article.