[A ROC analysis for comparing contrast perception in grey scale reversal of digital images].
Based on ROC (receiver operating characteristic) analysis, contrast perception by eight physicians engaged in x-ray diagnostics for different lengths of time was examined in respect of inversion of grey scale values of digital x-ray film images. The ROC analysis showed a significantly superior contrast perception for imaging by the negative mode (bones white) than by the positive mode (bones black). With r* = + 0.61 a positive correlation was obtained between the period of the physicians' activity in x-ray diagnostics and the difference between the areas below the ROC curves for both imaging modes. Hence, the negative mode is to be preferred for diagnostic work based on digital x-ray film images.
Dölken
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Institut für Röntgendiagnostik, Universität Würzburg.
Krahe
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Landwehr
P
P
Horwitz
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AE
Lackner
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K
D006801:Humans; D012372:ROC Curve; D011856:Radiographic Image Enhancement; D014796:Visual Perception / Q000502:physiology*