Related Experiment Video
Updated: Jun 25, 2025
Trabecular Meshwork Response to Pressure Elevation in the Living Human Eye
Published on: June 20, 2015
Test-Retest Reliability of Intraocular Pressure Measurements With Office-Based Versus Home-Based Rebound Tonometers
Tony Realini1, Kevin Halenda1, Joel Palko1
1Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV.
PréCis:
Intraocular pressure (IOP) measurements obtained with the HOME2 rebound tonometer are interchangeable with measurements obtained using the office-based IC100 and IC200 rebound tonometers, making characterization of circadian IOP achievable with no inter-device sources of variability.
Objective:
To evaluate test-retest reliability between IOP measurements obtained with a home rebound tonometer operated by patients and those obtained with office rebound tonometers operated by experienced clinical staff.
Methods:
After training and practice with a home rebound tonometer (iCare HOME2) in a randomly selected eye, patients with established or suspected open angle glaucoma underwent IOP measurement in the fellow eye as follows in randomized order: 3 good quality measurements with the iCare IC100 operated by experienced clinical staff, 3 good quality measurements with the iCare IC200 operated by experienced clinical staff, and 3 good quality measurements with the HOME2 operated by the patient. The Shrout-Fleisch intraclass correlation coefficient (ICC; 2,1) was the measure of reliability utilized based on the model using 2-way random effects, absolute agreement, and single measurement.
Results:
Thirty eyes of 30 patients were evaluated. The Pearson correlation coefficient ( r ) for IOP measurements taken with the IC100 and HOME2 was 0.97, with the IC200 and HOME2 was 0.96, and with the IC100 and IC200 was 0.97. Test-retest reliability between HOME2 and IC100 (ICC: 0.90), HOME2 and IC200 (ICC: 0.92), and IC100 and IC200 (ICC: 0.94) all reflected excellent test-retest reliability.
Conclusion:
The test-retest reliability of IOP measurements taken by patients using the iCare HOME2 self-tonometer compared with IOP measurements taken by trained operators using the iCare IC100 and IC200 tonometers was uniformly excellent (ICCs all ≥0.9). These findings indicate that these three devices should be considered interchangeable for the clinical assessment of circadian IOP.
More Related Videos
Related Concept Videos
01:23Assessment of blood pressure in brachial artery(two-step method)
01:21Sites for measruring blood pressure
The Brachial Artery: Primary Site for Blood Pressure Measurement
01:28Special considerations while measuring blood pressure
Monitoring Both Arms:
Monitoring BP in both arms during the initial assessment is advisable, as the systolic value may differ by five to ten mm Hg between arms. For subsequent BP assessments, use the arm with the higher reading.
01:15Assessment of blood pressure in brachial artery(one-step method)
Prepare for the Procedure:
01:10Pre-Procedural Guidelines for Assessing Blood Pressure
01:25Errors occurring during blood pressure monitoring
Several factors...