'l. Mammography uses a low-dose x-ray imaging system for examination of the human breast. Mammography is often used to diagnose breast cancer in women by identifying the presence of cancerous growths or tumors. Researchers wanted to compare the sizes of breast cancer tumors detected by mammography in Sweden and Canada. A total of 1,295 Swedish women and 880 Canadian women with breast cancer participated in this study. Tumor size was measured in centimeters