Incidence and prevalence are terms commonly used in describing disease epidemiology. The science builds on many sub-fields, including biology, biochemistry, physics, epidemiology, pharmacology, medical sociology. Classical immunology ties in with the fields of epidemiology and medicine. Digitization of forms facilitates the collection of data for epidemiology and clinical studies. NIDKK operates the Phoenix Epidemiology and Clinical Research Branch in Phoenix, AZ. Osterholm is a frequently invited guest lecturer on the topic of epidemiology of infectious diseases. Prospective cohort studies are considered to yield the most reliable results in observational epidemiology. Federal-funded research into firearm injury, epidemiology, violence, and prevention is minimal. Goldberger is remembered as the "unsung hero of American clinical epidemiology". It became an important case study in epidemiology. The credential awarded is CIC, Certification in Infection Control and Epidemiology. Epidemiology, medical ethics and questions on empathy are also emphasized. This experience sparked an interest in epidemiology and public health. There is a lack of comprehensive statistics about the epidemiology of frostbite. Causal models have found applications in signal processing, epidemiology and machine learning.