Psychiatric diagnoses

Psychiatric diagnoses are different from diagnoses of physical diseases.

There are no biomarkers for a psychiatric diagnosis – no images, no lab tests, no objective data. Physical diagnoses are based on tests and exams. Psychiatric diagnoses are based on conversations with the patient and other people:

Psychiatric screening tools are scripted interviews (a list of questions with possible answers) and rating scales (a list of symptoms to be rated according to severity).

The diagnosis depends on the answers to the interview, or/and the doctor’s rating of the symptoms.

There is no known brain disease that causes schizophrenia, bipolar disorder, depression, or any other condition described by a psychiatric diagnosis.

The concept that each psychiatric diagnosis may correspond to some yet undiscovered brain disease remains hypothetical. For now, words like “schizophrenia” or “bipolar disorder” refer to symptoms – hearing voices, having unusual beliefs and experiencing extreme mood changes.

If you talk and behave in a certain way, you have “schizophrenia.” This is similar to saying that, if your head hurts, you have a headache. Headache is a real problem, but it is not a diagnosis. Likewise, mood swings, or distressing voices telling you to do stupid things are real problems, but diagnoses that describe them are not “real” in the same sense as diagnoses of physical illnesses are.

To understand your, or loved one’s, condition, it is important to know the difference between physical and mental diagnostic procedures

Making a diagnoses includes three steps:

1. Interviewing the patient and compiling or verifying their clinical history: “Documentation of the current concern, past medical history, family history, social history, and other relevant information, such as current medications.”

2. Physical Exam: “A hands-on observational examination of the patient.”

3. Diagnostic Testing: “Laboratory medicine, anatomic pathology, and medical imaging” in physical medicine and “screening tools used in making mental health diagnoses” in psychiatry.

In diagnosing physical illness, these three steps are different in nature, but in diagnosing mental illness, they all consist of interviews and observations.

Diagnostic process for physical illness

is based on both medical symptoms and medical signs (biomarkers):

• During the interview, the doctor asks questions and hears about symptoms reported by the patient. Parents and guardians are interviewed when the patient is a minor or legally incompetent.

• A physical exam is “the process of evaluating objective anatomic findings.”

• It requires instruments, such as thermometer to take temperature, or stethoscope to hear better internal body sounds.

• Diagnostic testing is a lab analysis of bodily fluids or tissues and imaging, such as X-ray, ultrasound, or MRI performed by specially trained medical technologists using special equipment.

‍Physical exam and testing are used to find biomarkers of a specific disease.

Biomarkers are “medical signs – that is, objective indications of medical state observed from outside the patient – which can be measured accurately and reproducibly.”

For example:

— During the interview, the patient tells the doctor about cough and fever.

— During the physical exam, the doctor takes temperature and listens to the patient’s lungs.

— During the diagnostic testing, the patient’s nasal fluid is examined in a lab, and a chest X-ray is performed in another lab.

A presence of a specific virus in the nasal fluid, or white spots on the X-ray image can be biomarkers of Covid or pneumonia.‍ ‍

Diagnostic process for mental illness

is based on symptoms only (lab and imaging testing may be used to rule out physical reasons for altered behavior):

• During the interview, the doctor asks questions and hears about symptoms reported by the patient and by other people (e.g., family, roommates, colleagues, employers, police).

• During the physical exam, the doctor observes the patient’s behavior without any special instruments.

  Additionally, the patient may be hospitalized for 72 hours and observed by hospital staff members, who do not use any special instruments. They describe the patient’s behavior, and the doctor uses these descriptions when making a diagnosis.

• During the diagnostic testing, the doctor can use blood and urine tests to check for chemicals that affect behavior (e.g., alcohol, street drugs) and imaging tests of the brain to check for stroke, brain injuries, tumors and other physical reasons for the patient’s symptoms.

  If intoxication or brain damage are ruled out (everything looks normal), the doctor uses psychiatric screening tools.

  For example:

  — During the interview the patient tells the doctor about being threatened or persecuted by somebody; the doctor asks questions to evaluate whether this is true.

  — During the physical exam, the doctor observes that the patient looks scared; notes from the hospital staff state that the patient looks like they see something in the room that others are not seeing.

  — During the diagnostic testing, the doctor finds no mind-altering chemicals in the patient’s system and no physical brain damage.

  If the doctor comes to conclusion that nobody threatens or persecutes the patient in real life and that the staff observations indicate that the patient is out of touch with reality, the patient can be diagnosed with schizophrenia.