Let’s suppose you have a toothache and visit the dentist. The dentist will diligently follow a differential diagnosis process to address the toothache.

        First, the dentist asks questions to understand the patient’s health history, because the health history or medical condition like sinuses can affect the tooth.  Second, they begin to ask questions about the symptoms: What makes the tooth sensitive? Which tooth do you think it is? Third, they may take an x-ray. An x-ray clearly is not a 100 percent diagnosing tool (just like a standardized test). It’s only helpful for a diagnosis. The x-ray might provide direction on what may be going on or maybe not. Fourth, they take a clinical look in the mouth. Are there cracks? How much decay is in the mouth? Then, they may then tap on the tooth, spray air, cold water, or hot water on the tooth. With these steps, and using this body of evidence, the dentist may diagnose up to 95 percent of the root cause to address the toothache.