The clinical breast examination is an examination of the breast performed by a health care professional. The exam involves inspecting the breasts to look for asymmetry, skin dimpling, or masses. The breasts are subsequently palpated in both the upright and recumbent positions. The axillary and supraclavicular regions are palpated for the presence of abnormal lymph nodes. The American Cancer Society recommends a clinical breast examination by a health professional every three years for women between the ages of 20 and 39, and yearly for women aged 40 and older. Studies demonstrate increased breast cancer detection with a combination of clinical breast exam and mammography compared to mammogram alone. Despite this, no study has demonstrated a reduction in mortality resulting from the addition of the clinical breast exam to mammographic screening.