Journal of Current Science and Technology

ISSN 2630-0656 (Online)

Inter-instrument agreement of anterior corneal curvature measurements: Topographer, auto kerato-refractometer and manual keratometer


In this paper, inter-instrument agreement among topographer, auto kerato-refractometer and manual keratometer are the main concerns. The corneal steep, flat and average powers from the 61 right eyes of 61 healthy undergraduate students at Rangsit University were measured by three different instruments.  In statistical analysis, measurement concordance and correlation between pairs of instruments were analyzed by Bland-Altman analysis.  Intraclass correlation coefficient and paired t-test analysis were also performed.  It was found that the three instruments showed indifferent mean corneal steep and flat and average powers at a significance level of 0.05.  Therefore, topographer, auto kerato-refractometer and manual keratometer can be practically interchangeable.

Keywords: auto kerato-refractomete; Bland-Altman analysis; corneal curvature measurements; inter-instrument agreement; manual keratometer; topographer

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DOI: 10.14456/jcst.2021.14


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