The authors found no studies that specifically looked at the effectiveness of screening for osteoporosis, so they considered information about the frequency of osteoporosis, the accuracy of the screening tests, and the effectiveness of treatments for osteoporosis. The authors found strong evidence that older age, weight under 70 kg (154 pounds), and not taking estrogen were risk factors for osteoporosis and related fractures. They found less strong evidence for the following risk factors: smoking, weight loss, family history of osteoporosis, low physical activity, high alcohol or caffeine intake, and low vitamin D and calcium intake. Surveys designed to screen for osteoporosis were moderately useful. Bone density measurement using DEXA is the best available test to identify women who are at risk for an osteoporosis-related fracture. Several available medications reduce the risk for fracture in women with low bone density, but evidence is currently strongest for bisphosphonates.