The BI-BADS rating of breast nodules includes multiple characteristics of the nodule, such as its morphology, borders, blood flow and internal echogenicity. A score is given based on whether the manifestation of malignancy is clear on those factors. For example, a nodule with an irregular morphology, poorly defined borders, low internal echogenicity, and very rich blood flow is often malignant. However, if it has only one feature that resembles malignancy, it does not mean that the nodule is necessarily malignant, but it has to be judged in combination with its multiple features.