Table of ContentsView AllTable of ContentsPositive and Negative TestsFactors That Affect ResultsRelative Value TestsAt-Home Tests
Table of ContentsView All
View All
Table of Contents
Positive and Negative Tests
Factors That Affect Results
Relative Value Tests
At-Home Tests
There are two basic kinds of medical test results:
Thousands of medical tests are done to make diagnoses, measure the progression of a disease or condition, or monitor the effectiveness of treatment. But they all have some basic truths about what they mean and how they are best interpreted.
This article provides information about medical test results and the kinds of questions you’ll want answered to better understand what they mean.
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When you are given a medical test that yields a positive or negative result, you will need to know what the results mean and whether the result is trustworthy.
Positive and negative tests are typically used for diagnostic purposes to ascertain whether a disease or condition is present (positive) or not (negative). In layperson’s terms:
There are alsofalse-positive resultswhich means your test shows you have a disease or condition, but you don’t actually have it, andfalse-negative resultsin which a test shows you don’t have a disease or condition, but you really do.Certain tests have limitations and may be less accurate than others.
For example, you may be given anHIV test, and it comes back negative. Because the test detects proteins produced in response to the disease, rather than the disease itself, it may not be able to make an accurate diagnosis if you are tested too soon after HIV exposure.
Other tests have low specificity. This means the test may be able to detect certain organisms, but are less able to tell one strain of the organism from another.
What Is a Testing Window Period?
Factors That Affect Medical Results
If your test results are not what you expect, you may want to ask to be tested again. There are many ways mistakes can occur, usually because of errors in collecting, storing, or processing lab samples.
Once you have been diagnosed, further testing for that condition will usually yield relative results that will be important to you.
When you are given a medical test that yields relative results, usually in the form of a number (value), you will want to know what those results mean and how they compare to previous results.
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.
By definition, a relative value test is one that measures specific components of blood, urine, or other lab samples and compares those values to what would be expected in a normal, healthy population.
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. What is often more important is how values trend between tests, as this can indicate that a treatment is working or failing or if a disease is progressing or resolving.
Common Healthy Results for Medical Tests
Examples of healthy relative value results include:
Cholesterol results, also called a lipid panel, include several types of cholesterol and a blood fat called triglycerides. Healthy relative value results include:
Questions to Ask Your Healthcare Provider
Questions toask your healthcare providerabout relative tests include:
Ask for copies of your test results. 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.
What Common Blood Tests Mean
What to Know About At-Home Tests
At-home medical tests are kits you can buy online, at a pharmacy, or grocery store. The kits provide everything you need to collect a sample of body fluid or cells at home.
You may be able to read the results at home or you may need to send the sample to a lab to test for, screen, or monitor certain diseases and conditions.
Common at-home tests include:
At-home tests should never replace testing that your healthcare provider orders. Ask your provider or pharmacist to recommend test kits, and talk with your provider about your results, even if they’re normal.
Summary
Medical tests are done to make diagnoses, measure the progression of a disease or condition, or monitor the effectiveness of treatment. Test results may be positive, negative, inconclusive, or a relative number.
Several factors can affect test results. It’s important to talk to your healthcare provider about your test results to make sure you understand the results and what they mean for your health and possible treatments.
Why You Need an Appointment to Get Your Medical Test Results
7 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Medline Plus.How to understand your lab results.nam: aidsmap.False negative results on HIV tests.Plebani M.Diagnostic errors and laboratory medicine - causes and strategies.EJIFCC. 2015;26(1):7–14.American Heart Association.High blood pressure.American Diabetes Association.Blood glucose and A1C diagnosis.Johns Hopkins Medicine.Lipid panel.Medline Plus.At-home medical tests.
7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Medline Plus.How to understand your lab results.nam: aidsmap.False negative results on HIV tests.Plebani M.Diagnostic errors and laboratory medicine - causes and strategies.EJIFCC. 2015;26(1):7–14.American Heart Association.High blood pressure.American Diabetes Association.Blood glucose and A1C diagnosis.Johns Hopkins Medicine.Lipid panel.Medline Plus.At-home medical tests.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Medline Plus.How to understand your lab results.nam: aidsmap.False negative results on HIV tests.Plebani M.Diagnostic errors and laboratory medicine - causes and strategies.EJIFCC. 2015;26(1):7–14.American Heart Association.High blood pressure.American Diabetes Association.Blood glucose and A1C diagnosis.Johns Hopkins Medicine.Lipid panel.Medline Plus.At-home medical tests.
Medline Plus.How to understand your lab results.
nam: aidsmap.False negative results on HIV tests.
Plebani M.Diagnostic errors and laboratory medicine - causes and strategies.EJIFCC. 2015;26(1):7–14.
American Heart Association.High blood pressure.
American Diabetes Association.Blood glucose and A1C diagnosis.
Johns Hopkins Medicine.Lipid panel.
Medline Plus.At-home medical tests.
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