Expected findings - The individual will be able to discriminate between the hot and cold stimuli with 100% accuracy.

Equipment - Hot (115 to 120 °F) and cold (40 °F) metal probe thermometers or clean vials/test tubes filled with hot (115 to 120 °F) or cold (40 °F) water.

Testing procedure

1. Explain the procedure to the patient with his/her eyes open. For example, “I am going to touch various parts of your arms (or other body part) with these test tubes filled with hot and cold water, and when you feel the tube, tell me if it feels hot or cold.”
2. Demonstrate the procedure with the patient’s eyes open until the patient understands the procedure to be performed.
3. The patient closes his/her eyes, or vision is otherwise occluded.
4. Place the hot or cold test tube against the patient’s skin, making certain not to vary the surface area of contact between the test tube and skin or the pressure of contact.
5. Have the patient identify each stimulus as hot or cold. Make certain the appropriate temperatures of the stimulus objects are maintained throughout testing.
6. Vary the time between stimuli to avoid developing a rhythmic pattern. 
7. Repeat throughout suspected areas.
8. Document findings.