A method for assessing the presence and/or the severity of a lesion in an organ or tissue of a subject through automated analysis of at least one image of the organ or tissue is provided. In particular, the organ or tissue is a liver organ or liver tissue. The method includes the calculation of a score that combines descriptors of the image, and includes the steps of: a) measuring on the image at least two descriptors of the image, b) mathematically combining the descriptors in a score; and c) assessing the presence and/or the severity of a lesion in the organ or tissue based on the value of the score calculated at step b).