But they all have some basic truths about what they mean and how they are best interpreted.
For example, you may be given anHIV test, and it comes back negative.
Other tests have low specificity.

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These values can determine whether a treatment is working or a disease or condition is progressing.
The range of values can sometimes vary based on age, sex, and other factors.
Acomplete blood test (CBC)is a prime example of a relative value test.
Anything within the range of values is considered normal.
Anything above or below the range of values is abnormal.
Abnormal values don’t necessarily have diagnostic value but may indicate a developing concern.
You might ask for written documentation about where your healthcare provider thinks those relative values should be for you.
You might even consider tracking them over time as a way to manage your health.
Common at-home tests include:
At-home tests should never replace testing that your healthcare provider orders.
Test results may be positive, negative, inconclusive, or a relative number.
Several factors can affect test results.
Medline Plus.How to understand your lab results.
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Medline Plus.At-home medical tests.