Related Experiment Video
Updated: Dec 30, 2025
Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter
Published on: September 16, 2025
Repeatability of the amplitude of accommodation measured by a new generation autorefractor
Chang-Chi Weng1, De-Kuang Hwang1,2, Catherine Jui-Ling Liu1,2
1Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan.
Significance:
This is the first study to validate the repeatability of objective measurements of amplitude of accommodation (AA) using the TONOREF III (NIDEK Co., Ltd., Japan), which can measure the AA in 30 seconds.
Purpose:
To evaluate the repeatability of objective measurements of AA using the TONOREF III and explored the association between objectively measured AA and factors, including age, sex, spherical equivalent, baseline pupil size and pupil size change during accommodation.
Methods:
This cross-sectional study recruited 35 healthy subjects aged 26 to 52 years. The Bland-Altman method and intraclass correlation coefficients (ICCs) were used to assess the repeatability of TONOREF III measurements. The relationships between AA and age, sex, baseline pupil size, changes in pupil size (ΔPS) during accommodation were analyzed using linear regression for univariate and multivariate analysis.
Results:
The mean difference in AA (ΔAA) between two sessions of TONOREF III measurements was 0.23 D (95% CI: -1.07 to +1.53 D), while no significant correlation was found between the mean and ΔAA (p = .14). The ICCs of the TONOREF III was 0.96. Age, sex, and ΔPS during accommodation were significant factors affecting the AA in multivariate analysis.
Conclusions:
The repeatability of objective AA measurements using the TONOREF III was good. Measuring AA using the TONOREFTM III in clinical practice is feasible.
