Abstract
We have devised a package for the statistical analysis of computerized visual fields. It is based on a new mathematical model of the normal visual field and intended to facilitate interpretation of single fields and to illustrate changes over time in consecutive threshold fields. Single field analyses include maps showing pointwise total and pattern deviations from the age-corrected normal reference field. These maps are displayed both numerically, in dB, and as noninterpolated greyscaled probability maps illustrating the statistical significance of measured deviations. These probability maps help emphasize shallow, but significant, depressions in the paracentral field while frequently occurring false positive deviations occurring in the midperiphery are de-emphasized. Visual field indices, summarizing the deviations of height (Mean Deviation) and shape (Pattern Standard Deviation and Corrected Pattern Standard Deviation) of the measured field are weighted according to the normal variance among healthy individuals and printed out together with level of statistical significance. For follow-up the programme contains several different options. These range from an Overview format where threshold printouts and probability maps from several tests are printed in reduced size, but without any reduction of data, on a single sheet of paper, to a box plot format where the development of the field is shown with an intermediate degree of data reduction and a format employing a high degree of data reduction: graphs over visual field indices over time. If five or more tests are available a linear regression analysis of Mean Deviation is automatically performed. The programme will become available in the Humphrey Field Analyzer.
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© 1987 Martinus Nijhoff Publishers/Dr W. Junk, Publishers, Dordrecht
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Heijl, A., Lindgren, G., Olsson, J. (1987). A package for the statistical analysis of visual fields. In: Greve, E.L., Heijl, A. (eds) Seventh International Visual Field Symposium, Amsterdam, September 1986. Documenta Ophthalmologica Proceedings Series, vol 49. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-3325-5_23
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DOI: https://doi.org/10.1007/978-94-009-3325-5_23
Publisher Name: Springer, Dordrecht
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