ArticleOphthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists)2019
Calibration of the PlusOptix PowerRef 3 with change in viewing distance, adult age and refractive error.
Article in Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists), 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers.
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Who cites it
8 citing papers in PubMed.
- Undiagnosed visual disorders among first-grade children in Türkiye: a school-based photoscreening cross-sectional study with cost analysis.BMC ophthalmology · 2026Article
- Comparative Analysis of Physiological Vergence Angle Calculations from Objective Measurements of Gaze Position.Sensors (Basel, Switzerland) · 2024Article
- Focusing on mixed narrow band stimuli: Implications for mechanisms of accommodation and displays.Journal of vision · 2024Article
- Comparison of the PlusoptiX A16 and vision screener V100.Frontiers in ophthalmology · 2024Article
- Introducing Dynamic Stimulation Aberrometry: Binocular Objective Accommodation versus Subjective Measures.Ophthalmology science · 2023Article
- Quantification of Oculomotor Responses and Accommodation through Instrumentation and Analysis Toolboxes.Journal of visualized experiments : JoVE · 2023Article
- Transient Eye Shortening During Reading Text With Inverted Contrast: Effects of Refractive Error and Letter Size.Translational vision science & technology · 2022Article
- Calibration of the PlusOptix PowerRef 3 with change in viewing distance, adult age and refractive error.Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists) · 2019Article
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Authors and funding
4 authors.
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Abstract
purposeThe PowerRef 3 is frequently used in studying the near triad of accommodation, vergence and pupil responses in normal and clinical populations. Within a range, the defocus measurement of the PowerRef 3 is linearly related to the eye's defocus. While the default factory-calibrated slope of this relation (calibration factor) is 1, it has been shown that the slope can vary across individuals. Here, we addressed the impact of changes in viewing distance, age and defocus of the eye on the calibration factor.
methodsWe manipulated viewing distance (40 cm, 1 m and 6 m) and recruited participants with a range of accommodative capabilities: participants in their 20s, 40s and over 60 years old. To test whether any effect was larger than the range of measurement reliability of the instrument, we collected data for each condition four times: two in the same session, another on the same day, and one on a different day.
resultsThe results demonstrated that viewing distance did not affect the calibration factor over the linear range, regardless of age or uncorrected refractive error. The largest proportion of the variance was explained by between-subject differences.
conclusionsCalibration data for the PowerRef 3 were not sensitive to changes in viewing distance. Nevertheless, our results re-emphasise the relevance of calibration for studies of individual participants.
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