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Why It Is Done

Lab tests are generally done for one of the following reasons:

To find the cause of symptoms
To confirm a diagnosis
To screen for a disease. Screening tests are often done for people of a specific age or those who have a high risk for a specific disease.
To help rule out a disease or condition
To assess the severity of a disease
To monitor the progression of a disease, how well an organ is working, or if treatment is helping
To verify specific events (for example, DNA testing after a rape, or urine testing to look for drug use)

Many conditions can change your lab results. Your doctor will talk with you about any abnormal results as they relate to you.

WebMD Medical Reference from Healthwise

Last Updated: July 08, 2009

This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.