Screening and Diagnosis
Alice is a 45-year-old woman who has a positive screening mammogram. She asks her physician about the chance of this being actual breast cancer. The mammogram is 90% sensitive and 90% specific for detecting breast cancer, and the prevalence of breast cancer in her age group is approximately 1%. What is the probability that Alice has breast cancer?
Screening and diagnostic tests are important clinical tools for identifying diseases at an early stage and promoting treatments that benefit tested individuals. Careful implementation and interpretation of these tests are needed to avoid clinical confusion, restrain healthcare costs, and prevent unnecessary complications caused by follow-up procedures that are prompted by positive test results.