"The BI-RADS assessment categories are:
- 0- incomplete
- 1-negative
- 2-benign findings
- 3-probably benign
- 4-suspicious abnormality
- 5-highly suspicious of malignancy
- 6-known biopsy with proven malignancy
A BI-RADS category 4 mammogram has a positive predictive value of about 30%. A category 5 mammogram is almost certainly predictive of breast cancer with a positive predictive value of about 95%."