The extent of a chemosensory disorder can be determined by measuring the lowest concentration of a chemical that a person can detect or recognize. A patient may also be asked to compare the tastes of different chemicals or to note how the intensity of a taste grows when a chemical's concentration is increased.

Scientists have developed taste testing in which the patient responds to different chemical concentrations. This may involve a simple "sip, spit, and rinse" test, or chemicals may be applied directly to specific areas of the tongue.