Now let’s try applying the same concepts to another clinical situation. This time we will look at the sensitivity, specificity and positive and negative predictive values of otoscopic examination of the tympanic membrane (TM) to identify acute otitis media (middle ear infection).

You are working in a pediatric clinic with an experienced pediatrician. You examine 50 children whose parents are concerned about the possibility of ear infection. You believe that 15 children have red and bulging tympanic membranes consistent with otitis media (OM). The pediatrician examines these same children and makes a diagnosis of otitis media in 25 children.

Please start the 2x2 table.