A new study conducted by researchers from the University of Michigan Medical School and Harvard Medical School revealed that 46% of antibiotics prescribed at 514 outpatient clinics were prescribed without an infection-related diagnosis. In addition, the study showed that clinicians prescribed 20% of antibiotics outside of in-person visits. According to a general internist Jeffrey Linder at Northwestern University Feinberg School of Medicine, 80% of all antibiotic prescriptions are made at the outpatient setting. Centers for Disease Control and Prevention (CDC) has estimated that 30% of antibiotic prescriptions in the US are unnecessary. Most often antibiotics are prescribed to acute respiratory tract infections (ARIs), but most ARIs are viral infections for which antibiotic treatment is ineffective. These figures demonstrate more in depth the problems with outpatient antibiotic prescribing and illustrate how much antibiotics are used without proper targeting.