Ruling Out Conditions for a Mental Health Diagnosis in Teens

Therapists rule out various mental health issues when they meet with teens.
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The term "rule out" is used by mental health professionals who are trying to make an accurate diagnosis. The symptoms of many mental health conditions are similar or overlap so before a clear diagnosis can be made, clinicians must rule out a variety of other conditions.

If your teen is having trouble concentrating, a therapist may want to rule out ADHD or PTSD. Or, if your teen seems depressed, a mental health professional may want to rule out bipolar disorder before making a depressive disorder diagnosis. 

Figuring Out the Right Diagnosis

Finding an accurate diagnosis for troubled teens can be difficult and initially several possible mental health disorders may seem to explain your teen's emotional or behavioral problems.

Because of this, the process of finding a correct diagnosis is conducted in a logical, step-by-step manner that considers all the possibilities, and then narrows them down to the diagnosis or diagnoses (sometimes more than one) that most closely match your teen's symptoms.

Getting the right diagnosis is extremely important in order to be able to successfully treat your teen's symptoms. It's a mental health professional's job to use different methods to figure out exactly which disorder in the Diagnostic and Statistical Manual (DSM-5) fits your teen best.

Through this process, which is also used with medical conditions, the most accurate diagnosis is reached through a process of elimination. A clinician determines the best diagnosis by methodically discarding the ones that do not fit. 

An Example of the Difficulty of Diagnosis

Defiant behavior may be a symptom of several conditions, such as oppositional defiant disorder, depression, or substance abuse. But a little defiance may not necessarily signal a mental health issue.

Oppositional behavior may also stem from past trauma or learned behavior from an unhealthy group of friends. The mental health professional evaluating this teen is likely to say, “First we will rule out depression, then we will consider other possibilities.”

Steps Mental Health Professionals Use to Rule Out Diagnoses

Mental illnesses aren't always cut and dried. Professionals don't simply use a checklist to arrive at a diagnosis.

Instead, most conditions are diagnosed after a series of interviews where a clinician considers an individual's background and environment.

This is important because symptoms need to be taken in context. For example, a teen who is misbehaving at school may be acting out because they have a learning disability or because they are bullied, not necessarily because they have a primary behavior disorder.

  1. The mental health professional will gather information about your teen. A thorough history is obtained and the clinician will consider information from a variety of sources, including the teen, parents, physician, and teachers. A clinician may interview everyone or might provide forms to fill out.
  2. Substance abuse issues are considered. If there is substance abuse involved, the clinician needs to figure out to what degree your teen's symptoms may be due to the substance abuse or if they are abusing the substance because of the psychiatric symptoms. Depression and anxiety disorders, for example, often increase a teen's risk for substance abuse.
  3. Medical problems are considered. The next step is ruling out a medical condition as the cause of your teen's psychiatric symptoms. For example, an untreated thyroid condition can cause depression. 
  4. Environmental issues are assessed. Sometimes, mental health issues stem from stressful life events. Past trauma or a recent change, such as moving to a new city, may temporarily cause problems for a teen.
  5. Psychiatric issues are considered. Mental health providers will use the DSM-5 to consider potential mental health disorders. Symptoms are compared and a clinician may establish a clear diagnosis. 
  6. The impact on your teen's life is considered. A clinician will consider how much functioning is impaired. A clinician will evaluate whether your teen's symptoms are impacting their life enough to warrant a diagnosis. Mild anxiety that doesn't impact a teen's social life, education, or work may not meet the requirement for mental health diagnosis.

How to Get Help For Your Teen

If you suspect your teen may have a mental health condition, seek professional help. Start by talking to your teen's physician. Express any concerns you have about your teen's mood or behavior.

Your teen's physician may make a referral to a therapist, psychiatrist, or other mental health professional. A thorough assessment and evaluation can help a clinician rule out specific mental health conditions while also arriving at an accurate diagnosis if a diagnosis is warranted.

3 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. LeBano L. Six Steps to Better DSM-5 Differential Diagnosis. Psychiatry & Behavioral Learning Network.

  2. Post by Former NIMH Director Thomas Insel: Transforming Diagnosis. National Institute of Mental Health.

  3. Ghosh A, Ray A, Basu A. Oppositional defiant disorder: current insightPsychol Res Behav Manag. 2017;10:353–367. Published 2017 Nov 29. doi:10.2147/PRBM.S120582

By Amy Morin, LCSW
Amy Morin, LCSW, is a psychotherapist and international bestselling author. Her books, including "13 Things Mentally Strong People Don't Do," have been translated into more than 40 languages. Her TEDx talk,  "The Secret of Becoming Mentally Strong," is one of the most viewed talks of all time.