Patient & Family Guide to Laboratory Testing:
Frequently Asked Questions (FAQs)
Disclaimer: This guide provides general information about laboratory tests. For any questions or concerns regarding your specific lab results, always consult your physician or healthcare provider to ensure you get the most accurate advice for your situation.
Your Laboratory Test Results
What influences the time it takes to get my lab results?
The time it takes to receive lab results—commonly referred to as turnaround time (TAT)—depends on several factors, including:
● In-House Testing vs. Send-Outs: Not all lab tests your physician orders can be performed in the hospital laboratory, as some tests need special equipment or expertise. These tests are sent to outside laboratories. Tests performed within the hospital laboratory generally have faster turnaround times compared to those sent to external reference labs.
● Test Complexity: Routine tests (e.g., complete blood count, basic metabolic panel) typically return results within hours, while specialized tests (e.g., genetic testing) may take days to weeks.
● Specimen Transport & Processing: The time needed to transport, prepare, and analyze samples can also affect TAT.
● STAT vs. Routine Orders: Urgent (STAT) tests are prioritised over routine tests but may still take time depending on the lab's workload and the complexity of the test being performed.
Why does my result have a flag for ‘high’ or ‘low,’ but my clinician said everything looked “normal”?
A reference range is a set of values that is considered “normal” for a specific test and represents values found in 95% of a healthy population. Lab reports often flag results as high (H) or low (L) based on these predefined reference ranges. However:
● Individual Variability: A slightly high or low value may not be clinically significant based on your medical history and overall health. Even in a group of 100 healthy individuals, only 95 (i.e., 95%) will have results in the reference range. The remaining 5 (i.e., 5%) will not.
● Context Matters: Your clinician interprets results in the context of your symptoms, history, and other test results before making medical decisions.
Why have I seen my abnormal results, but my clinician hasn’t contacted me?
Due to the 21st Century Cures Act, patients often receive electronic access to their test results as soon as they are available. However:
● Clinicians Need Time for Interpretation: Your provider may need additional time to review results, compare them with past tests, and determine the best course of action before contacting you .
● Not All Abnormal Results Are Concerning: Some flagged results may not require immediate follow-up, but your clinician may discuss them at your next visit if needed.
● If You Have Concerns, Reach Out: If you see abnormal results and have not heard from your provider, you are encouraged to contact their office for clarification.
Preparing for Laboratory Tests
Why do I have to prepare for some lab tests but not others?
Certain lab tests require special preparation to ensure accurate results. Common reasons include:
● Fasting (e.g., glucose levels, lipid panels): Eating before these tests can alter blood sugar and cholesterol levels.
● Timed Testing (e.g., cortisol levels, drug levels): Some tests must be collected at specific times of the day due to natural fluctuations.
● Medication Restrictions (e.g., coagulation studies, hormone testing): Some medications can interfere with lab results, so clinicians may ask you to pause certain drugs before testing.
● Hydration & Diet: Dehydration or certain foods can affect some tests (e.g., creatinine, potassium levels).
Always follow the instructions provided by your healthcare team to ensure the most accurate results.
Variability in Lab Results
Why are my results different when tested at different hospitals or labs?
Lab tests are not always standardized across different healthcare institutions. Variability can arise due to:
● Different Laboratory Methods & Equipment: Labs may use different instruments to perform testing, which can produce slight differences in results.
● Reference Ranges May Vary: Ranges are often determined by the patient population served by that specific lab.
● Sample Handling & Processing: How your sample was stored, transported, and processed can impact final results.
● Point-of-Care Testing vs. Laboratory Testing: Some tests performed at the bedside may differ from those analyzed in a central lab due to differences in testing methodologies.
If you notice a significant difference in your lab results between two tests, contact your doctor to discuss whether the changes are important for your health.
Importance & Value of Routine Lab Testing
Why are routine lab tests important?
Routine lab testing helps monitor overall health, detect diseases early, and guide medical decisions. Common benefits include:
● Early Disease Detection: Conditions like diabetes, anemia, and kidney disease may be detected before symptoms arise.
● Monitoring Chronic Conditions: Tests help track treatment effectiveness for conditions like hypertension and thyroid disorders.
● Medication Management: Certain tests ensure medications (e.g., blood thinners) are at safe and effective levels.
● Pre-Surgical Screening: Labs can identify potential risks before procedures, improving patient safety.
Questions or Concerns?
If you have questions about your lab tests, do not hesitate to reach out to your healthcare provider or the laboratory for further clarification.
Source:
American Society for Clinical Pathology (ASCP), Negotiation & Advocacy Toolbox, Understanding Your Lab Test Results. https://www.supportcdconelab.org/toolbox/pillar-1/
