Medical terminology is confusing. Australian doctors have to study for at least seven years before being able to practice1, so we can be forgiven for not knowing the difference between a murmur and a flutter, heatstroke and a hot flush, or when we’ll need to swallow the bitter pill that we’re being told about.
A common mixup in the medical world is the difference between signs and symptoms. The words are synonyms, and tend to be used interchangeably when describing medical conditions, despite there being a clear distinction between the two.
In the medical world, a sign is a health issue that can be observed. This might be a skin rash that indicates eczema, the rasping sound of a bronchitis cough, or red rings around the eyes brought on by dermatitis. Signs can be identified by anyone, but should be professionally diagnosed by doctors, who have the training and experience to identify their possible cause. Many signs are able to be measured by doctors, which is an important part of the diagnosis.
The most important medical signs are called vital signs, and include your heart rate (pulse), breathing rate, temperature, and blood pressure. Doctors observe these signs to diagnose various medical problems. During operations, when the patient is at a higher level of risk, vital signs are closely observed to monitor their health status5.
Signs can indicate symptoms. If a person is squinting their eyes and rubbing their temples, this could be a sign that they’re experiencing symptoms of pain, possibly from a headache. If your pregnant partner wakes up and flies to the bathroom like a bat out of hell, her vomiting is probably a sign of nausea symptoms, as a result of morning sickness.
Pathology has four different signs in total, which are as follows.
A diagnostic sign is one that helps a doctor to diagnose a medical problem. On days with high pollen counts, if you find yourself congested, constantly sneezing, and with itchy red eyes, these are diagnostic signs of a pollen allergy.
A pathognomic sign is the same as a diagnostic sign, but with much greater certainty. An example of a pathognomic sign is a bronze-like skin pigmentation, caused by Addison’s Disease.
A prognostic sign forms part of a prognosis—a predicted health outcome for a patient. Doctors use prognostic signs to predict what will happen to a patient. A common example is a breast cancer lump, which when combined with other telltale prognostic signs, can determine the patient’s chance of survival3.
An anamnestic sign is an indicator of a past medical condition. A common example of an anamnestic sign is somebody with visible paralysis on one side of their face, after suffering from a stroke4.
A symptom is the subjective experience of a potential health issue, which cannot be observed by a doctor. Examples include stomach cramps as a result of eating undercooked meat, a throbbing headache brought on by stress, or an overwhelming feeling of fatigue. The doctor cannot see, hear, feel, or smell any of these issues, which makes them symptoms, not signs. If you’re having symptoms, you’re the only person who can describe them.
There’s three different types of symptoms:
Chronic symptoms tend to recur over a long period of time. For somebody suffering from undiagnosed heart disease, chronic symptoms can include chest pain, palpitations, and breathlessness2, which return regularly.
Relapsing symptoms are symptoms that have occurred previously, were considered to be resolved, but have returned. Depression symptoms are a common example, which can strike again after years of being absent.
Remitting symptoms are symptoms that improve or disappear. If a person had regular headaches, and those headaches haven’t appeared for a long time, they can be described as remitting symptoms.
Sign vs symptom
A sign is an objective, observable phenomenon that can be identified by another person. A symptom is a subjective experience that cannot be identified by anyone else.
Put simply—a sign is objective, and a symptom subjective. A doctor can usually diagnose a medical condition more easily if they have observable signs, and a subjective description of a patient’s symptoms.
Examples of signs vs symptoms
|Medical issue||Sign (objective)||Symptom (subjective)|
|Common cold||Runny nose||Sinus pain from congestion|
|Chickenpox||Spots and blisters||Fatigue|
|Type 2 diabetes||Poor wound healing||Thirst|
|Coronary heart disease||Fast heart rate||Chest pain|
|COVID-19||Fever||Loss of taste or smell|
|Depression||Withdrawing from friends||Feelings of misery|
- Becoming a Doctor: How Long Does It Take?, i-student-global
- Chronic Heart Disease, Sunrise Medical Centre
- Coral Omene, Amy Tiersten, 2010, Prognostic Factor – an overview, Principles of Gender-Specific Medicine (Second Edition)
- Medical sign, Wikipedia
- Rod Brouhard, EMT-P, 2019, Medical Signs Versus Symptoms, Verywell Health