Diagnostic Testing A-Z

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    AIDS Walk

    Join Quest Diagnostics for AIDS Walk New York City, San Francisco, and Los Angeles

  • How To Request a Test

    How to Request a Test

    When you visit your physician or other healthcare professional, go prepared. You may have heard about a new medical study, a new medication or a new laboratory test that might be right for you.

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    What is the ColoVantage® Blood Test?

    Your doctor can order ColoVantage® as part of routine blood testing. The convenient test doesn’t require you to avoid certain foods or involve any advance preparation. But it can aid in the detection of colorectal cancer.

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    What Is Fasting and Do I Need to Fast?

    When your healthcare provider orders certain tests, you may be told to fast for several hours before the test or overnight. Here’s what you need to know to comply with your doctor’s instructions.

Explore "The 9 Visual Rules of Wellness"

Rule #1 is baseline your health.  Learn more from

Learn About a Test

Learn about various tests at, a public resource on clinical lab testing.

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Popular and Featured Tests

Talking to Your Doctor About Prescription Drug Testing

Prescription pain-relief drugs require careful monitoring to ensure that they are used as intended.