Tests and diagnosisBy Mayo Clinic staff
If your doctor or mental health provider believes you may have obsessive-compulsive disorder, he or she typically runs a series of medical and psychological tests and exams. These can help pinpoint a diagnosis, rule out other problems that could be causing your symptoms and check for any related complications.
These exams and tests generally include:
- Physical exam. This may include measuring height and weight; checking vital signs, such as heart rate, blood pressure and temperature; listening to your heart and lungs; and examining your abdomen.
- Laboratory tests. These may include a complete blood count (CBC), screening for alcohol and drugs, and a check of your thyroid function.
- Psychological evaluation. A doctor or mental health provider will talk to you about your thoughts, feelings and behavior patterns. He or she will ask about your symptoms, including when they started, how severe they are, how they affect your daily life and whether you've had similar episodes in the past. You'll also discuss any thoughts you may have of suicide, self-harm or harming others. Your doctor may also want to talk to your family or friends, if possible.
Diagnostic criteria for obsessive-compulsive disorder
To be diagnosed with obsessive-compulsive disorder, you must meet the criteria spelled out in the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV). This manual is published by the American Psychiatric Association and is used by mental health professionals to diagnose mental illnesses.
For OCD to be diagnosed, you must first meet these general criteria:
- You must have either obsessions or compulsions.
- You must realize that your obsessions and compulsions are excessive or unreasonable.
- Obsessions and compulsions significantly interfere with your daily routine.
Your obsessions must meet these specific criteria:
- Recurrent and persistent thoughts, impulses or images are intrusive and cause distress.
- The thoughts aren't simply excessive worries about real problems in your life.
- You try to ignore or suppress these thoughts, images or impulses.
- You know that these thoughts, images and impulses are a product of your own mind.
Compulsions must meet these specific criteria:
- Repetitive behavior that you feel driven to perform, such as hand washing, or repetitive mental acts, such as counting silently.
- These behaviors or mental acts are meant to prevent or reduce distress about unrealistic obsessions.
It's sometimes difficult to diagnose obsessive-compulsive disorder because symptoms can be similar to those of generalized anxiety disorder, depression, schizophrenia or other mental illnesses. Be sure to stick with it, though, so that you can get appropriate treatment.
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