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How Do You Diagnose a Mental Illness?

Getting a professional assessment is critical.

I’m often asked a lot of questions about how mental illnesses are diagnosed. What’s the diagnostic process? How is a specific diagnosis determined? Are diagnoses helpful or harmful? Let’s try to address some of these frequently asked questions now.

How are mental illnesses diagnosed?

The word diagnosis is defined in two different ways. It not only means “the act of identifying a disease, illness, or problem by examining someone” but it also refers to “a statement or conclusion that describes a disease or illness.” Similarly, the process for diagnosing a mental illness reflects both of these definitions and can be boiled down into three major steps:

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1. Gathering information

A mental health professional will first gather information from a person through a detailed interview which includes finding out the person’s main concerns, their symptoms, and their life history. Additional information is sometimes obtained from the person’s family or caregivers and from previous treatment records. A physical examination, lab tests, and psychological questionnaires may be included, often to rule out other illnesses.

2. Narrowing down the options

As all of this information is obtained and integrated, the professional will begin to determine if the person’s symptoms match up with one or more official diagnoses. Each diagnosis is made up of a list of common signs or symptoms. The professional will compare the symptoms the person is experiencing with the list of symptoms that comprises a specific diagnosis. If the person’s symptoms closely match the ones on the official list for a particular disorder, the diagnosis can then be made.

3. Forming a diagnostic impression

After all the information is reviewed, the professional will form an initial or tentative impression, using established diagnostic terms. There are well over two hundred different diagnoses for mental disorders. For example, schizophrenia, bipolar disorder, agoraphobia and alcohol use disorder are examples of diagnoses. It’s not unusual for someone to have more than one diagnosis, particularly if they are dealing with multiple problems at the same time.

What are some of the benefits from an accurate diagnosis?

Obtaining an accurate diagnosis can be helpful in several ways:

  • Getting the right diagnosis is an extremely important step because effective treatments for that illness can then be recommended and started.
  • Understanding your diagnosis can be a source of hope and relief. You begin to learn that your condition is shared by others, that effective treatments are available and that recovery is possible.
  • Health care providers use diagnostic terms to communicate with other professionals to coordinate treatment.
  • Typically a formal diagnosis is required by insurance companies in order to reimburse the provider for your care and treatment.

What are some of the concerns about diagnosis?

Diagnosis of a mental illness is not without potential drawbacks. Some of these include:

  • Sometimes the wrong diagnosis is made. Different illnesses can have similar symptoms, so it may appear a person has one illness when they actually have another one. Also the health care provider may not have enough information about the person or their symptoms to arrive at the right diagnosis.
  • When an incorrect diagnosis is made, the wrong treatments may be recommended, which could be of little or no benefit, or even detrimental to the person.
  • Sometimes a person will “buy in” to their diagnosis and start acting in a manner consistent with how they think a person with that illness would behave. For example, if a person sees themself as “depressed,” they may limit themselves and act as they assume a depressed person might behave, such as withdrawing from other people or not displaying much emotion.
  • Some diagnoses and labels related to mental illness or addiction create prejudice or discrimination when used inappropriately. This could mean that the person with the diagnosis is treated unfairly, denied services or opportunities, ridiculed, or may receive negative reactions from others because they have been labeled as “mentally ill.”

You can see how the diagnosis of mental health conditions is often a very sensitive topic. Where do I stand? While I fully understand the concerns related to diagnosis, I believe it’s important to have an accurate determination of one’s condition by a health care professional in order to benefit from the most effective options for treatment and recovery.

Copyright David Susman 2018

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