🩺Diagnostic Tests

    Understanding Lab Test Results: A Comprehensive Guide to Taking Control of Your Health

    Everyone deserves to understand their health through clear and accessible information. This inclusive guide helps you make sense of your lab test reports, interpret your lab test results in the context of your life, and ask the lab test questions that lead to real answers. Whether you’re reviewing a routine panel or navigating complex results, you’ll find practical steps, examples, and expert insights to help you take charge of your care with confidence.

    Tamara Lobban-Jones, Contributing Writer
    Understanding Lab Test Results: A Comprehensive Guide to Taking Control of Your Health

    Understanding Lab Test Results: A Comprehensive Guide to Taking Control of Your Health

    Table of Contents

    Introduction

    Understanding your clinical laboratory test results isn’t just “nice to have,” it can be the difference between catching a problem early and missing it until it becomes dangerous. Numbers on a page drive many medical decisions, yet many reports are written for clinicians, not patients. When results are misunderstood, diagnoses are delayed, treatments get off-track, and anxiety spikes. When results are understood, trends are spotted sooner, risks are addressed faster, and care becomes a true partnership. This guide translates laboratory data into plain language, so you can ask better lab test questions, avoid common pitfalls, and use your results to protect your health.

    Key Takeaways

    • Understanding saves lives: Clear interpretation catches problems early, reduces errors, and guides the right treatments.
    • Context and trends matter most: Always use your lab’s reference interval, compare against your personal trend, and factor in fasting, timing, hydration, medications, illness, and stress.
    • Think in panels, not single numbers: Read related markers together and pay attention to subtle shifts—like rising RDW or “normal” ferritin during inflammation.
    • Advocate with humans: Ask precise questions (“What are we ruling in or out? When should we recheck?”) and lean on MLS/DCLS experts—because everyone deserves clear, equitable answers.

    When you receive clinical laboratory test results from your medical provider, do you understand what those numbers actually mean? You're not alone if the answer is no. Millions of patients receive lab test reports each year without fully comprehending the information contained within them. This knowledge gap can lead to missed diagnoses, delayed treatment, and unnecessary anxiety. Understanding your lab test results is a fundamental component of taking charge of your healthcare. Whether you're managing a chronic condition, investigating unexplained symptoms, or simply maintaining wellness through routine screening, knowing how to interpret your lab test reports empowers you to have more meaningful conversations with your healthcare providers and to make informed decisions about your health.

    This comprehensive guide will help you navigate the often-confusing world of clinical laboratory testing, answer common lab test questions, and provide you with the tools you need to become an active participant in your healthcare journey.

    Why Understanding Your Lab Test Results Matters

    Healthcare providers order millions of laboratory tests daily, yet studies suggest that many patients leave their appointments without a clear understanding of what their results mean or what actions they should take. This disconnect doesn’t reflect a lack of understanding. Lab test reports are written for medical professionals, not the people receiving the results.

    Laboratory results contain technical terminology, reference intervals that vary by age and gender, and abbreviations that can seem like a foreign language. Add to this the time constraints many physicians face during appointments, and it becomes clear why so many people struggle to understand their lab test results.

    When you don't understand your lab test results, several problems can arise:

    • Delayed diagnosis occurs when subtle abnormalities that warrant further investigation go unnoticed.
    • Medication errors can happen when results are misunderstood, leading to incorrect adjustments
    • Unnecessary anxiety from not knowing what "slightly elevated" or "borderline" means
    • Missed opportunities for early intervention when changes in lab values over time aren't recognized
    • Poor adherence to treatment plans when you don't understand why a test was ordered or what it measures

    The real-world impact of this knowledge gap extends far beyond confusion. When patients can’t make sense of their lab test results, they may overlook early warning signs, miss opportunities to prevent disease progression, or experience unnecessary anxiety over normal fluctuations.

    When patients do understand their results, everything changes. They become empowered participants in their care, able to recognize trends, ask informed questions, and make confident decisions grounded in real data about their health.

    Yet what’s often overlooked is who makes this understanding possible. Behind every accurate lab test result stands a Medical Laboratory Scientist (MLS), a highly trained healthcare professional who performs and analyzes the vast majority of tests that guide diagnoses and treatments. These professionals are the unsung heroes of modern medicine: essential members of the care team who rarely meet patients but whose expertise influences nearly every medical decision.

    Research shows that roughly 70 percent of all clinical decisions rely on laboratory data produced by these professionals. With more than 14 billion laboratory tests ordered each year, according to the Centers for Disease Control and Prevention (CDC), MLS experts truly form the scientific backbone of healthcare.

    Working behind the scenes, they operate sophisticated instruments, validate results for accuracy, detect patterns across multiple tests, and uphold the highest standards of quality before results ever reach your provider. They are the quiet guardians of diagnostic accuracy, translating biological data into information clinicians can trust.

    In many ways, Medical Laboratory Scientists are the bridge between science and understanding. They know what can cause false results, recognize subtle variations that signal early disease, and understand how different conditions or medications can alter test outcomes. Recognizing their role isn’t just about honoring expertise, it’s about ensuring that every patient has access to clarity, accuracy, and informed care.

    In recent years, a new and essential role has evolved to strengthen this bridge between the laboratory and the clinic: the Doctor of Clinical Laboratory Science (DCLS). Building upon the foundation of the MLS, DCLS professionals expand their expertise beyond the bench to consult directly with physicians, pharmacists, nurses, and patients. They interpret complex testing patterns, recommend follow-up investigations, and help prevent diagnostic errors, transforming raw data into actionable insight at the point of care.

    In essence, DCLS practitioners make the invisible visible. They ensure that laboratory findings are not only technically accurate but also clinically meaningful. By engaging directly with healthcare teams, they enhance diagnostic precision, reduce unnecessary testing, and advance equitable outcomes—especially for patients whose concerns have too often been overlooked or dismissed.

    Together, the MLS and DCLS professions exemplify what Diagnostic Equity stands for: science serving humanity through clarity and connection. They are the living bridge between laboratory science and lived experience, proving that true healthcare happens when data becomes dialogue.

    A movement with a heart: the pioneer behind the platform?

    The Diagnostic Equity platform is shaped by pioneers in laboratory medicine and patient communication, including Dr. Susan Leclair, a widely respected educator and voice for patient-friendly interpretation. Her influence underscores a simple but transformative idea: reference intervals are guideposts, not absolutes, and real understanding begins when your numbers are interpreted in the context of your life.

    In 2019, Diverse Health Hub was launched to explore different dimensions of health equity, and later the Diagnostic Equity platform was developed to further that mission.

    Today, a community of nearly three dozen credentialed experts from different disciplines (Clinical Chemistry, Hematology, Microbiology, Immunology/Immunohematology, Molecular/Genetics) respond to questions from around the world, because everyone deserves a clear explanation of their lab test results, not just those with extra time in the exam room.

    Understanding your lab results helps you spot trends early, communicate clearly, and make informed decisions with less fear and more confidence.

    How to Read a Lab Test Report (Step-by-Step)

    Every lab test report is a story told in numbers. Here’s a simple, repeatable way to read yours:

    • Confirm the basics
      * Test name (e.g., Complete Blood Count/CBC, Comprehensive Metabolic Panel/CMP, Hemoglobin A1C)
      * Date & time of collection (timing can change results, especially for glucose, cortisol, and some hormones)
      * Fasting vs. non-fasting (if fasting was required but not followed, results may be misleading)

    • Find your result, the reference interval, and the units
      Example: Glucose: 97 mg/dL (70–99)
      Reference intervals (sometimes also known as reference ranges or “normal ranges”) show where most healthy people fall, but they don’t define what’s ideal for you. Units of measurement matter; a number without units can’t be compared meaningfully. In this example the units of measurement are mg/dL (milligrams per deciliter)

    • Check for flags
      High (H), low (L), or an asterisk (*) indicates something outside the listed range. Small deviations are common and not always worrisome.

    • Compare to your typical ranges
      Track your own trend line over time. A value that’s “within range” can still be concerning if it’s a big change from your personal history.

    • Look at related markers together
      Laboratory tests are grouped together for a reason. Together they construct a picture in context. For example, in a CBC, hemoglobin, hematocrit, MCV, and RDW tell a richer story about the red blood cells together than any number alone.

    • Note medication and life-context factors
      New meds, supplements, intense exercise, dehydration, or a recent illness can shift results.

    • Write down your questions
      Use the question prompts later in this guide to structure a focused, productive conversation with your clinician.

    Common Lab Tests Explained: CBC, CMP, Lipids, Thyroid, A1C

    Below are the tests most people encounter. Many questions submitted on this platform include many of these test names. Each bullet lists what the test generally looks for and what certain patterns may mean. (These are examples, not diagnoses.)

    What it measures: Red blood cells (RBC), hemoglobin (Hgb), hematocrit (Hct), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), red cell distribution width (RDW), white blood cells (WBC), Differential (Diff which contains absolute number of each cell type,, specific percentages of these cells when compared to each other, quality comments, and platelets. (PLT, MPV, PDW, and PCT)

    What it can suggest:

    • Low Hgb/Hct/RBC: Possible anemia (e.g., iron, vitamin B12, folate deficiency; chronic disease; blood loss)
    • MCV high: Larger RBCs—can point to vitamin B12/folate deficiency or other causes
    • MCV low: Smaller RBCs—can point to iron deficiency or certain inherited traits
    • RDW high: Wider variation in RBC size—an early hint of bone marrow stress, mixed anemia, or recovery phase
    • WBC high: Infection, inflammation, stress response, certain meds
    • WBC low: Some infections, marrow suppression, medication effects
    • Platelets low or high: Bleeding risk vs. clotting risk signals—context is crucial

    Hidden gem: RDW can whisper “something’s off” before other values change. Persistent or rising RDW deserves attention even when Hgb and MCV look normal.

    Comprehensive Metabolic Panel (CMP)

    What it measures: Glucose; electrolytes (sodium, potassium, chloride, CO₂/bicarbonate); kidney markers (BUN, creatinine, (eGFR); liver markers (ALT, AST, ALP, bilirubin; proteins (albumin, total protein)

    What it can suggest:

    • Glucose: Short-term blood sugar snapshot; elevated values may suggest pre-diabetes/diabetes; confirm with A1C or repeat tests
    • Electrolytes: Hydration status, nerve and muscle function; significant imbalances can cause cramps, confusion, or heart rhythm issues
    • BUN/Creatinine/eGFR: Kidney filtration; rises can reflect dehydration or true kidney dysfunction—compare with your typical ranges
    • ALT/AST/ALP/Bilirubin: Liver stress or injury; mild elevations can accompany meds, alcohol, or strenuous exercise
    • Albumin/Total Protein: Nutritional status, liver synthesis, or kidney/gut protein loss

    Lipid Panel

    What it measures: Total cholesterol, LDL (“bad”), HDL (“good”), triglycerides

    What it can suggest:

    • High LDL: Plaque-building risk—managed with diet, activity, meds as needed
    • Low HDL: Less protective clearing of LDL
    • High triglycerides: Often linked to diet, insulin resistance, or genetics; very high levels require urgent attention
    • Fasting matters: Some labs allow non fasting lipids, but fasting can still improve accuracy for triglycerides. Ask your clinician what they recommend for you.

    Thyroid Function Tests

    What it measures: TSH (screening), Free T4 (active hormone), sometimes Free T3

    What it can suggest:

    • High TSH + Low Free T4: Hypothyroidism (underactive)
    • Low TSH + High Free T4/T3: Hyperthyroidism (overactive)
    • Normal TSH but symptoms present: Discuss repeat timing, antibodies (e.g., TPO), or other causes

    Hemoglobin A1C (HbA1c)

    What it measures: Average blood sugar over ~3 months

    What it can suggest:

    • 5.7–6.4%: Pre-diabetes range (discuss lifestyle changes and monitoring)
    • ≥6.5%: Diabetes range (confirm with repeat and discuss treatment options)
    • Rapid changes: Consider anemia, kidney disease, or conditions that affect red blood cell lifespan, which can skew A1C
      • Remember: A1C is an average. Glucose swings may still require attention even if your A1C looks “fine.”

        This isn't just about individual confusion—it's a diagnostic equity issue. When certain communities face language barriers, shorter appointment times, or providers less familiar with how conditions present differently across populations, the gap between test results and understanding widens.

    Think about it: Two patients might get the exact same blood test, but one walks out understanding what it means and what to do next, while the other leaves with a printout full of confusing numbers and no clear answers. That's not fair, and it's not random.

    Who gets left without answers? Often, it's patients who need medical interpreters but can't access them. It's women whose symptoms get dismissed as "just anxiety" when something physical is actually wrong. It's older adults whose treatable conditions get waved off as "normal aging." It's anyone without the time, resources, or confidence to push back and demand clearer explanations.

    The result? Real harm. Missed diagnoses. Delayed treatment. Worse health outcomes, not because of differences in biology, but because of differences in how the healthcare system treats people.

    Diagnostic equity means ensuring everyone has equal access not just to testing, but to clear, accurate interpretation of what those tests mean. Your ZIP code or postal mail code, primary language, race, gender, or insurance status shouldn't determine whether you get answers to your lab test questions. The same lab value can mean different things for different people, and truly personalized medicine requires understanding your unique context, your statistical trends, and your lived experience.

    That's exactly why platforms like this exist to level the playing field so everyone can understand their results, not just those with extra time in the exam room or the confidence to keep asking questions.

    We hear these lab test questions often. Here are concise, plain language answers you can trust as a starting point.

    Q: My results are “normal,” but I still feel unwell. What now?
    A: Two possibilities: (1) Your body is compensating (for example, the bone marrow working overtime so numbers look okay), or (2) we’re not testing the right thing at the right time. Ask for trend comparisons, repeat timing, or related tests that complete the picture.

    Q: Do I need to fast before my blood work?
    A: It depends. Lipids and some glucose tests often require 8–12 hours of fasting. Iron studies and CMP may, too. If you ate when fasting was required, tell the phlebotomist (again a trained, certified staff member who collects your specimen) or your provider, as results can be misleading.

    Q: A value is flagged high/low. Should I panic?
    A: Not usually. Mild shifts can reflect dehydration, stress, exercise, or time of day. Context, symptoms, and trends matter far more than a single flag. It is important to have that conversation with your provider who can connect the results to your current status.

    Q: How soon should I repeat an abnormal lab?
    A: Your clinician will guide you. Some results warrant same day confirmation; others need weeks. Ask, “What is the ideal retest window and why?”

    Q: Can medications change my lab test results?
    A: Yes. Blood pressure meds, statins, antibiotics, steroids, thyroid hormones, supplements, and even high-dose biotin can alter certain tests. Share everything you take.

    Q: What numbers should I memorize?
    A: Start with your typical trends for hemoglobin, creatinine/eGFR, lipids, and A1C (if relevant). Knowing your personal normal helps you spot meaningful change early.

    Q: Should I use direct to consumer (DTC) tests?
    A: They can be useful, but lack of clinical context can confuse. If you go with DTC, plan ahead for how you’ll interpret results and with whom you’ll discuss them.

    lab test tubes

    When “Normal” Isn’t Normal (Hidden Signals)

    Numbers within range can hide important clues. Here are common “quiet signals” to discuss with your care team:

    • Rising RDW with normal Hgb/MCV: Early marrow stress or mixed deficiency—consider iron, vitamin B12, folate, blood loss, or recovery phase.
    • “Normal” ferritin in chronic inflammation: Ferritin is an acute phase reactant; normal doesn’t always mean “iron stores are fine.” Consider transferrin saturation or a full iron panel.
    • Gradual trends over time: A dip from Hgb 15 → 12 g/dL over months is meaningful even though both values may be inside range.
    • Timing matters: Cortisol, some thyroid parameters, sex hormones, and glucose can vary by hour. Testing at the wrong time can miss the signal.
    • Hydration and activity: Dehydration concentrates results; heavy exercise can transiently alter enzymes and other markers.

    Please note: The reference intervals mentioned in this article are examples only. Each laboratory uses different testing methods and equipment, which means reference intervals can vary. For an accurate interpretation of your clinical laboratory results, always refer to the specific range provided on your report by the lab that performed your analysis.

    Disease-Specific Considerations: Understanding Your Unique Lab Test Results

    For individuals with sickle cell disease, understanding lab test results is particularly crucial because values differ significantly from the general population. Knowing your personal values becomes essential for detecting complications early. As Maya Bloomberg, a hematology nurse practitioner, explains, these typical ranges vary not just from healthy individuals but also between different sickle cell genotypes. Hemoglobin SC patients generally have higher hemoglobin ranges than Hemoglobin SS patients, and recognizing these differences matters when interpreting acute changes.

    Hemoglobin resultsrepresent the most critical value for sickle cell patients to know. In the typical sickle cell disease patient, hemoglobin results ranging from 7 to 11 g/dL are common and lower than the standard reference interval of 12 to 18 g/dL seen in non-sickle cell patients. A hemoglobin of 8 g/dL might indicate severe anemia requiring urgent intervention in someone with a historical trend of 11 g/dL, while representing the stability for someone whose hemoglobin typically runs 7 to 8 g/dL. During emergency department visits for pain crises, healthcare providers unfamiliar with your statistical trends might dismiss your concerns if your hemoglobin falls within your typical range, not recognizing that any decrease from your personal typical ranges can indicate significant problems requiring treatment.

    The reticulocyte count measures immature red blood cells and reflects bone marrow activity. In sickle cell disease, the reticulocyte count is typically elevated because the body constantly replaces destroyed cells. This ongoing high level of red blood cell production represents your body's attempt to maintain adequate oxygen delivery despite the chronic destruction of sickled cells. However, an unexpectedly low reticulocyte count combined with low hemoglobin suggests the bone marrow isn't compensating appropriately, which could indicate kidney disease affecting erythropoietin production, infection suppressing bone marrow function, or other complications. The kidneys produce erythropoietin, a hormone that stimulates red blood cell production, so kidney damage from sickle cell disease can impair this response.

    White blood cell count patterns in sickle cell disease also provide important clinical information. Chronically elevated WBC indicates ongoing inflammation from repeated sickling episodes and vascular occlusions, and may predict who will benefit from hydroxyurea therapy. Bloomberg notes that patients with lower white blood cell counts while on hydroxyurea tend to have better clinical outcomes, even with identical fetal hemoglobin levels. This occurs because white blood cells and platelets are "sticky" cells that worsen vascular blockages during sickling crises. Hydroxyurea intentionally reduces these cell counts to the lower end of normal, improving blood flow and reducing crisis frequency.

    Conversely, persistently elevated white blood cell counts despite optimal medical therapy might indicate undertreated disease requiring additional interventions or consideration of newer therapies like gene therapy or bone marrow transplantation.

    Bilirubin levels in sickle cell disease warrant particular attention because elevated bilirubin causes the yellowing of eyes, or jaundice, commonly seen in this condition. The chronic breakdown of damaged sickled red blood cells produces excess bilirubin that the liver must process.

    While bilirubin elevation is expected, significant increases signal increased red blood cell destruction that should prompt consideration of hydration status, rest needs, and stress management. Bloomberg advises patients to ask themselves when jaundice worsens: "What am I doing that might be contributing to this? Is it a matter of me needing to drink more water? Am I overdoing it and need to rest? Do I need to manage my stress and start saying no or asking for help?" These practical questions help patients identify modifiable factors affecting their disease activity.

    For investigating chronic fatigue, a condition affecting millions, laboratory tests play a crucial role in identifying physical causes that require treatment. Dr. Susan Leclair, an expert in laboratory medicine, emphasizes that while fatigue can stem from psychological factors like depression or anxiety, laboratory testing can identify physiological causes that must be addressed before attributing symptoms solely to mental health. The challenge lies in fatigue being a symptom rather than a sign such as blood pressure, only the patient can feel it, making it difficult for providers to quantify or evaluate objectively.

    The essential screening tests for fatigue evaluation include:

    • Complete blood count with differential to rule out anemia and infection
    • Comprehensive metabolic panel to evaluate kidney, liver, and metabolic function
    • Thyroid function tests since hypothyroidism ranks among the most common treatable causes of fatigue
    • Vitamin B12 and folate levels, as deficiencies cause anemia and neurological symptoms including profound fatigue
    • Vitamin D levels, since deficiency associates with fatigue and muscle weakness Iron studies including ferritin to identify iron deficiency, the most common cause of anemia worldwide

    However, interpreting these results requires clinical context. Ferritin interpretation in someone with chronic inflammation differs dramatically from interpretation in an otherwise healthy person. Dr. Leclair emphasizes the importance of asking the right questions about fatigue duration and pattern. Fatigue the week before Thanksgiving when you're preparing a large family meal has different implications than persistent fatigue lasting weeks or months without clear cause.

    Primary care physicians are trained to ask when fatigue increases or decreases over time, whether other symptoms accompany it like joint pain suggesting chronic inflammation or breathing difficulty suggesting cardiopulmonary disease, and whether the fatigue improves with rest or persists regardless of sleep quality. These clinical details guide which lab tests to order and how to interpret the results within the full context of your health picture. The correct interpretation depends on the person in front of the numbers.

    Sickle Cell Disease (SCD)

    • Lower hemoglobin is expected compared to general population ranges; track your personal steady state.
    • Reticulocyte count (immature red blood cells) is typically elevated as the marrow compensates. If both Hgb and retic drop, that’s a signal worth urgent attention.
    • Bilirubin is often higher due to ongoing red blood cell turnover; sudden jumps can indicate increased hemolysis or dehydration.

    Chronic Fatigue Evaluation

    • Start with a CBC, CMP, thyroid panel, vitamin B12/folate, vitamin D, and iron studies.
    • Ask about test timing, recent illness, sleep quality, and meds/supplements that affect energy.
    • If clinical laboratory test results are unrevealing, discuss next questions (sleep apnea? chronic inflammation? mental health?) rather than stopping at “normal.”

    Tailor testing to your history, symptoms, and goals. “Normal” is the beginning of a conversation, not the end.

    health consumer with questions

    Asking the Right Lab Test Questions: How to Advocate for Yourself

    Navigating healthcare appointments effectively requires preparation and assertiveness, especially when lab test results are involved and appointment times are limited. Making the most of brief encounters with your healthcare provider demands strategic thinking about how to communicate your concerns and to ensure your questions get addressed.

    Before Your Appointment:

    • Obtain copies of your lab test reports in advance, so you can review them thoughtfully. Many laboratories have the ability to either send you a hard copy or email the results.
    • List your symptoms specifically, documenting when they occur, their severity, and what makes them better or worse.
    • Note all medications and supplements you're taking, including over-the-counter (OTC) products.
    • Prepare written questions, prioritizing your most important lab test questions at the top.

    During your appointment, Dr. Leclair offers powerful advice for patients whose providers dismiss their concerns or attribute symptoms to psychological factors without adequate investigation. "I want you to sit up as straight as you can, look your provider in the eye and say, 'Okay, that's nice that you don't think anything's going on. I'm telling you something is going on.'" This direct approach acknowledges your provider's perspective while firmly asserting that your symptoms are real and deserve investigation.

    Key Questions to Ask:

    "What do you think could be causing my symptoms besides 'it's in my head'?" This question forces your provider to generate differential diagnoses and consider physical causes. Then wait for the answer, fighting the urge to fill the silence with nervous talking gives your provider time to think through possibilities.
    <"What are you going to do about it? What tests will you order?" This moves the conversation from abstract possibilities to concrete action plans.
    "What specific answers are you looking for in those tests?" Understanding what results would confirm or rule out suspected diagnoses helps you interpret your lab test reports when they return.
    "What should be within the reference interval, and what will we do if values are too high or too low?"
    "If we don't get the answers you expect, what's your second hypothesis?" This asks your provider to share their internal prioritization of possible diagnoses, preparing you for alternative paths if initial testing doesn't provide clear answers.
    .

    Understanding Lab Test Limitations:

    Ask your provider directly about test accuracy, whether medications might affect results, if repeat testing is needed to confirm findings, and whether testing at a different time of day would be more informative. No medical test is perfect, all have sensitivity (ability to detect disease when present) and specificity (ability to correctly identify absence of disease). Understanding these limitations helps you interpret both positive and negative results appropriately.

    medical laboratory scientist at microscope

    The Critical Role of Context in Lab Test Results

    Laboratory values don't exist in isolation, they must be interpreted within the complete context of your clinical picture, lifestyle, and individual circumstances. The same laboratory value can have completely different meanings for different people depending on numerous contextual factors that affect both the values themselves and their clinical significance.

    Pre-Analytical Factors that significantly influence lab test results include:

    • Fasting status: Did you eat before testing when fasting was required?
    • Hydration: Dehydration concentrates blood components, artificially elevating many values
    • Exercise: Vigorous activity before testing affects multiple lab values through muscle enzyme release and fluid shifts
    • Medications: Both prescription and over-the-counter drugs can interfere with tests
    • Time of day: Many hormones and other substances follow circadian rhythms
    • Stress: Can elevate glucose, white blood cells, cortisol, and numerous other markers

    Patient-Specific Factors add another layer of necessary context:

    • Age: reference intervals change dramatically throughout the lifespan
    • Gender: Different normal ranges exist for males and females due to hormonal differences
    • Pregnancy: Dramatically alters numerous lab values to support the growing fetus
    • Ethnicity: Historically influenced some reference intervals, though this is being reconsidered
    • Underlying chronic diseases: Affect how we interpret multiple lab values

    The evolution of reference intervals reflects growing understanding of how social factors rather than genetics drive many population health differences. Recent years have seen important changes in how reference intervals are established, particularly regarding race-based adjustments. Historical race-based adjustments to reference intervals for tests like hemoglobin, creatinine, and glomerular filtration rate are being eliminated across many health systems. As Maya Bloomberg notes, "We're now acknowledging that these racial disparities are often due to systemic racism as opposed to genetics itself." This shift recognizes that race is a social construct rather than a biological determinant of health, and that environmental factors, access to healthcare, nutrition, stress from discrimination, and other

    These race-based reference intervals historically led to underdiagnosis of conditions like anemia and kidney disease in African American patients, delaying treatment and contributing to health disparities. For example, if a lower hemoglobin is considered "normal" for African Americans, mild anemia might be missed and left untreated, leading to ongoing fatigue and reduced quality of life.

    Similarly, race-adjusted calculations for kidney function led to delayed recognition of kidney disease progression in African American patients, potentially delaying referral for transplant or other advanced treatments. Eliminating these race-based adjustments represents an important step toward diagnostic equity, ensuring everyone receives accurate diagnosis and timely treatment regardless of their race or ethnicity.

    When to Seek Expert Help (How Diagnostic Equity Works)

    Even with a great clinician, there are moments when you need more time and clearer explanations. That’s why this platform exists.

    Why people come to Diagnostic Equity

    • Their lab test results are confusing or conflicting.
    • They have persistent symptoms but “normal” laboratory test results.
    • They want a “second set of eyes”, from people who read laboratory test results every day.
    • They need an answer in plain language that honors their lived experience.

    Who answers your questions

    Your questions are answered by a team of over 35 credentialed clinical laboratory scientists representing multiple specialties. These are real people, never chatbots, who combine technical expertise with empathy. Following a specialized mentorship, they translate complex science into clear, useful insights you can apply in real life.

    Privacy and process at a glance

    1. You submit your lab test questions and any relevant context.
    2. Identifying details are removed to protect your privacy.
    3. Your question routes to an appropriate expert within the Pro Hub.
    4. A reviewed, plain language answer comes back, usually within 1–2 business days.
    5. After 30 days, only an anonymized version of the question is retained.

    Important: The platform offers education and interpretation support and does not replace your own clinician’s diagnosis or treatment plan. We encourage and equip you to take our explanations back to your care team.

    The laboratory of the future will look and function very differently. Automation will accelerate processes, artificial intelligence will refine analysis, and data will flow more seamlessly between systems and clinicians. Yet one element must never change: the human presence guiding it all. Because while machines can measure, only people can interpret meaning.

    Every data point represents a human being with a unique history, biology, and story. And it takes another human, a Medical Laboratory Scientist, a Doctor of Clinical Laboratory Science, a provider, or an informed patient to recognize what those numbers truly signify.

    As Dr. Susan Leclair so powerfully reminds us, the laboratory is not a room full of machines; it is a living ecosystem of intelligence, ethics, and empathy. Technology may expand what we can do, but it is people who determine why we do it and how that knowledge improves lives.

    That is the heart of Diagnostic Equity: ensuring that every person, regardless of background or circumstance, has access not only to accurate testing but to understanding.

    When patients comprehend their results, when providers see the context behind the data, and when laboratory professionals are recognized as essential partners in care, medicine becomes more than a system. It becomes a dialogue rooted in trust, transparency, and shared humanity.

    The future of lab testing isn’t about choosing between humans or machines. It’s about ensuring that technology serves human insight, not the other way around. Because the most advanced diagnostic tool will always be the human mind, and the most powerful result will always be understanding.

    Behind every lab result is a person and behind every person is a story worth understanding.

    Get clarity from the experts who make that possible. Check out our FAQ Page or connect with our team of human laboratory professionals to interpret your results, ask questions, and make confident, informed choices about your health. Get Human Help →

    Please note: The reference intervals mentioned in this article are examples only. Each laboratory uses different testing methods and equipment, which means reference intervals can vary. For an accurate interpretation of your clinical laboratory results, always refer to the specific range provided on your report by the lab that performed your analysis.

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    Diagnostic Equity Resources

    Diagnostic Equity Resources

    Staring at your lab test report with lab test questions? Understanding your lab test results starts here.

    This information is not a substitute for, nor does it replace professional medical advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a healthcare professional.