Memory Effects in Subjective Quality Assessment of X-Ray Images

Experiments with human observers is considered as the most precise way for the assessment of image quality. Although widely used, such experiments have its pitfalls and hazards. In this work we investigate if the quality rating of previously viewed images influence the rating given to the current image, which we refer to as the rating memory effect. A subjective experiment with a group of observers rating x-ray images of different radiation dose was used for the basis of the analysis. The results indicate a memory effect, meaning that the rating of an image can be influenced by the ratings given in previously judged images.