Signs vs. Symptoms: Understanding the Key Differences

When reading about medical diseases and illnesses, you will notice that there are often lists of signs and symptoms. These terms may seem interchangeable, but although both are indicators of an illness or injury, they have otherwise completely different definitions. There are many differences between signs and symptoms.

Objectivity vs. Subjectivity

• Signs are objective, which means that they are more obvious and observable by doctors and others. Symptoms are subjective, which means that only the patient perceives them. Signs typically include bruising, an open wound or high temperature, while symptoms include nausea, vertigo, diarrhea and chills.

Description

• Patients typically visit a doctor because of their symptoms. Because symptoms are more subjective, the patient will have to be as descriptive as possible so that the doctor can diagnose the problem. However, since signs are visible, they will not require the same type of description because the doctor will already be able to notice them.

Verification

• Because only the patient experiences symptoms, the doctor cannot verify them. Symptoms such as fatigue, pain and dizziness are not measurable. Signs, however, can actually be measured by a physician. Rapid heart rate, blood pressure and fever are examples of signs that a doctor can measure.

Visibility and Vagueness

• Symptoms may be vague to the physician, while signs may not be noticed or mean anything to the patient. Signs are an objective and visible indication of an illness or injury that the patient is experiencing. These signs will lead the doctor to detect the problem.