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Erratum: Calculating the error in refractive error

The Original Article was published on 22 July 2011

Correction to: Eye (2011) 25, 1333–1336; doi:10.1038/eye.2011.169; published online 22 July 2011

Since the publication of the above article, the authors have noticed that further testing of the spreadsheet calculations in the article has revealed, in a predictable and limited set of special circumstances, that the spreadsheet calculations return a recognisable error. No candidates have been incorrectly scored as a result. The error is rectified in the following code, which also simplifies the number of calculation steps required.

If, at this stage, a dioptric power of the error is desired, as previously described, this correcting refraction can be converted as follows:

Unconventional results still occur with special scenarios, such as a one axis being entered as zero and the other as 180 (results in zero cylinder power at 135), and one axis 10, the other (minus) −170 (result zero cylinder power at 90). The calculated dioptric defocus equivalent would still be calculated correctly.

The authors would like to apologise for this mistake.


Additional information

The online version of the original article can be found at 10.1038/eye.2011.169

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Taylor, R., Ellingham, R., Subramaniam, S. et al. Erratum: Calculating the error in refractive error. Eye 26, 622 (2012).

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