Each time a patient receives treatment, a detailed record is maintained containing observations, medical or surgical interventions and treatment outcomes. In addition, patients provide information including family history, x-ray and lab results and treatment plans. Coders are responsible for assigning a code to each specific diagnosis or procedure. They consult classification manuals but also rely on their acquired knowledge of disease processes. Coders have a wide variety of career choices, including doctors’ offices, hospitals, insurance companies and physician billing services.