False Positive Test Result Blood Work

What is False Positive Test Result?

A false positive test result occurs when a laboratory test incorrectly indicates the presence of a condition, substance, or antibody that is not actually present in your body. It is caused by cross-reactivity with other antibodies, technical laboratory errors, medication interference, recent vaccinations, or individual biological variations. The Hepatitis B Core Antibody Total test is the most important confirmatory test when false positives are suspected, as it commonly requires additional verification to distinguish true infection from cross-reactive antibodies.

RECOMMENDED TEST Hepatitis B Core Antibody, Total
What's included
Fast & easy, results by email & SMS
No extra fees paid at the lab
No need to visit a doctor
Private & confidential
No insurance needed
Results explained
Why Private MD Labs?
90-day money-back guarantee Lab order in minutes Save a trip to the doctor Low prices since 2005 Labs within 2 miles

What causes false positive test results?

False positive test results are caused by several factors including cross-reactivity with other antibodies in your body, technical errors during laboratory processing, and interference from medications or supplements. Recent vaccinations can trigger antibody production that mimics disease markers, while autoimmune conditions may produce antibodies that react with test components. Biological variations such as pregnancy, liver disease, or other infections can also create substances in your blood that interfere with test accuracy, leading to incorrect positive readings even when the target condition is not present.

What is the best test for confirming a false positive result?

The Hepatitis B Core Antibody Total test is the most important confirmatory test when false positives are suspected because it frequently requires additional verification to distinguish true Hepatitis B infection from cross-reactive antibodies. When this test shows a positive result without other supporting markers like Hepatitis B Surface Antigen, additional confirmatory testing is essential to determine whether antibodies represent actual viral exposure or a false positive reaction. Follow-up testing typically includes more specific assays or different testing methodologies that can eliminate cross-reactivity and provide definitive answers about your true health status.

When should I get confirmatory testing for a false positive?

You should get confirmatory testing immediately if you receive an unexpected positive test result that does not match your symptoms or risk factors. Get tested if you have a positive result for a condition you have been vaccinated against, if your healthcare provider suspects test interference from medications or supplements, or if an initial positive conflicts with subsequent negative results. Anyone with positive results for infectious diseases without known exposure, or those with autoimmune conditions receiving unexpected positive findings, should pursue confirmatory testing to avoid unnecessary anxiety and inappropriate treatment decisions.

What are the symptoms of a false positive test result?
False positive test results do not cause physical symptoms themselves, but rather create a mismatch between test findings and your actual health status. You might have no symptoms at all despite a positive test indicating disease, or your symptoms might not match the condition the test identified. The key indicator is receiving a positive laboratory result when you have no clinical signs of the tested condition, no known exposure to infectious agents, or when subsequent testing produces conflicting results that suggest the initial finding was incorrect.
Who is at risk for false positive test results?
People taking multiple medications or supplements face higher risk of false positives due to test interference, while those with autoimmune diseases like lupus or rheumatoid arthritis often produce antibodies that cross-react with various test components. Pregnant women experience biological changes that can trigger false positives on certain tests, and individuals recently vaccinated may show positive results for antibodies without actual infection. People with liver disease, kidney dysfunction, or other chronic conditions have altered blood chemistry that increases the likelihood of test interference and inaccurate positive findings.
What happens if false positive test results are not confirmed?
If false positive test results are not confirmed through additional testing, you may undergo unnecessary treatments with medications that have serious side effects and health risks. Unverified positive results can lead to incorrect diagnoses in your medical record that affect insurance coverage and future healthcare decisions. The psychological impact of believing you have a serious condition when you do not can cause significant anxiety and stress, while unnecessary treatments waste financial resources and time. False positives for infectious diseases may lead to partner notification and contact tracing that creates social complications when no actual infection exists.
Can false positive results be identified with blood tests?
Yes, false positive results can be identified through confirmatory blood testing using different methodologies or more specific assays that eliminate cross-reactivity. Repeat testing with the same or alternative test methods helps verify initial findings, while testing for additional markers related to the suspected condition provides a more complete picture. For example, if Hepatitis B Core Antibody tests positive, checking for Hepatitis B Surface Antigen and other viral markers can confirm whether true infection exists or the initial result was a false positive due to antibody cross-reactivity.
How are false positive test results managed?
False positive test results are managed through confirmatory testing using more specific laboratory methods that can definitively rule out the suspected condition. Healthcare providers review your medical history, medications, recent vaccinations, and symptoms to identify potential causes of test interference. Once a false positive is confirmed, the incorrect result is documented in your medical record with notation that additional testing ruled out the condition. No treatment is needed for false positives themselves, but addressing any underlying conditions that contributed to the false result may be necessary to prevent future testing complications.
How can I prevent false positive test results?
You can reduce false positive risk by informing your healthcare provider about all medications, supplements, and recent vaccinations before testing. Schedule blood work at optimal times, avoiding testing immediately after vaccinations or during acute illnesses that might interfere with results. Choose laboratories that use high-quality testing methods with established accuracy rates and participate in quality control programs. When receiving unexpected positive results, always pursue confirmatory testing rather than accepting initial findings, and ensure your healthcare provider considers your complete clinical picture including symptoms, exposure history, and risk factors before making treatment decisions.
What can I do at home after receiving a false positive result?
After receiving a potential false positive result, gather all relevant medical records including vaccination history, medication lists, and previous test results to share with your healthcare provider. Keep a symptom journal noting whether you experience any signs of the condition the test identified, as the absence of symptoms supports the likelihood of a false positive. Avoid starting any treatments or making major lifestyle changes until confirmatory testing is complete. Research your specific test to understand known causes of false positives, but rely on your healthcare provider for interpretation rather than self-diagnosis, and schedule confirmatory testing promptly to resolve uncertainty.
How’s this work?
Getting your blood test with us is easy, private & backed by the power of science.

Long story short:
  1. In the test options, use the filters or search box to narrow your choices and find the test you want.
  2. If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test.
  3. Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout.
  4. If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want.
  5. When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system.
  6. Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way.
  7. You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy!
  8. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.
How do I know which test to get?
In the test options, find the test you want. If you’re not sure which test to get, we can lend a hand in finding the right option.

Just text or call us at 754-799-7833, email us at support@privatemdlabs.com, and we'll gladly help you. We've got your back and reply quickly.
Is it possible to make changes to my lab order if I made a mistake with the name, date of birth, or any other details?
Absolutely! We totally understand that errors can happen. No worries, we're here to help you.

Just reach out to us via text at 754-799-7833 or shoot us an email at support@privatemdlabs.com. Remember to include your order number and let us know the correct information you’d like to update. Our awesome team will jump right in and make sure everything is sorted out and accurate for you.

There are no changes necessary if your address is wrong on the requisition though. We don’t mail anything out.

Our lab requires an address to be listed to generate an order.
Do you accept health insurance?
Only HSA & FSA is accepted.

Our services are strictly self-pay and cannot be submitted to your health insurance provider except for Health Savings Accounts or Flexible Savings Accounts.

This policy applies to all insurance companies, including federal health insurance programs like Medicare.

If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com.
Can I cancel my order?
Yes.

We get it – sometimes your needs change.

As long as your samples haven’t been collected yet, we’re happy to help you cancel your order.

If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com.

You can read more about our cancellation policy here.
How can I find a lab location near me?
During the ordering process, you’ll be able to select a specific lab near you, with no strings attached! You can switch it up later easily and visit any of our authorized locations as long as it’s the same lab company you selected your test for (Quest Diagnostics or Labcorp).

Before you proceed with your order, feel free to browse through all our lab locations here. This will give you the peace of mind of knowing that there's a lab nearby your home, office or your favorite gym.

If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.
Here’s how easy it is to get blood work done on your terms
Choose a checkup
Order your test Save a trip to the doctor. Your results will come with clear, friendly explanations. Takes 2 minutes
Book a lab
Book an appointment Visit any of our 4,000 nearby lab locations to have your samples collected. Book or walk-in
Choose a checkup
Get results Receive a clear, easy-to-digest health report by email & SMS within a few business days. Get answers, fast

Here’s why 1,000,000+ customers chose us for affordable hassle-free private blood testing.

You get clinical lab reports & simplified health insights.
Save time & gas, go straight to the lab. Our doctors cover the rest.
Results start landing the next day after your lab visit.*
We don’t sell or share your data. Your time & privacy matter.
US-licensed doctors have your back if things get unclear.
No hidden fees, nice discounts for regular checkups.
Save a trip to the doctor, go directly to the lab
Instant orders, results often overnight*
Results explained in simple language
Reviewed by US licensed doctors
Fast & confidential, we never sell or share your data
No insurance needed, transparent pricing
Demo results
Testosterone 375 ng/dL
Demo results
Normal Optimal 400 - 1000 High
375 ng/dL

What this means

Your testosterone levels are slightly below the optimal range. While this is not necessarily cause for concern, it may contribute to occasional fatigue, reduced motivation, or lower muscle mass over time.

* Regular blood test results (e.g., CBC) typically start arriving the next business day after sample collection. More complex tests, such as hormone panels, may take up to 10–15 business days due to their complexity.

Us vs. Them

Not overhyped or overpriced. Just comprehensive blood testing made simple and for everyone.

* Regular blood test results (e.g., CBC) typically start arriving the next business day after sample collection. More complex tests, such as hormone panels, may take up to 10–15 business days due to their complexity.

1,000,000+ blood tests later, here's what our customers say

Google reviews 505 reviews Next
Hepatitis B Core Antibody, Total
What's included
Fast & easy, results by email & SMS
No need to visit a doctor
Private & confidential
No insurance needed
Results explained
No extra fees paid at the lab

Sample results

Sample image
For you & your coach Health insights Written in human language, backed by science.
Sample image
For you & your doc Classic lab report A familiar and comprehensive lab report.

Ask AI

Your 24/7 Lab Guide

Quick questions:

Which test is right for my symptoms?
What could be causing this?
When should I get tested?
A
Hi, I'm AI. I can help you find the right test, explain results, or prepare for your visit. What can I help with?
Just now
A
AI provides insights, not medical diagnoses.