Which Diagnostic Test For What?
Which Diagnostic Test Is Right for What?
There are numerous medical tests available today, each designed to detect, diagnose, or monitor specific health conditions. Often, multiple tests are used together to confirm a diagnosis, assess the severity of a condition, or monitor treatment progress.
Diagnostic tests serve various essential purposes, including:
- Screening – Detecting potential health issues before symptoms appear.
- Diagnosis – Identifying the cause of a patient’s symptoms.
- Staging or Severity Assessment – Determining how advanced or serious a condition is.
- Monitoring – Evaluating how well a treatment is working over time.
Some tests may serve multiple roles. For example, a blood test can detect anemia (a low red blood cell count), and the same test may be repeated after treatment to see if red blood cell levels have improved. In some cases, treatment may even begin during or immediately after the test, especially for urgent conditions.
Major Categories of Diagnostic Tests
Most diagnostic tests fall into one of the following six broad categories. Understanding these categories can help patients and caregivers grasp why certain tests are recommended.
1. Bodily Fluid Analysis
One of the most common types of diagnostic testing involves analyzing fluids from the body. These tests can detect infections, inflammation, organ function, and more. Common fluids tested include:
- Blood – Used to evaluate organ function, infections, anemia, hormone levels, and more.
- Urine – Helps detect kidney problems, infections, or metabolic disorders.
- Cerebrospinal Fluid (CSF) – Surrounds the brain and spinal cord; tested for meningitis, bleeding, or neurological conditions.
- Joint (Synovial) Fluid – Collected from joints to identify arthritis, infections, or gout.
- Other Fluids – Less frequently, saliva, sweat, and gastric juices are tested in specific conditions.
- Pathological Fluid Accumulations:
- Ascitic Fluid – Collected from the abdominal cavity (ascites) to check for liver disease, infection, or cancer.
- Pleural Fluid – Drawn from the space around the lungs (pleural effusion) to evaluate for infections, heart failure, or malignancies.
2. Imaging Tests
Imaging tests create pictures of the internal structures of the body. They are widely used to detect abnormalities, injuries, tumors, infections, or blockages and are often non-invasive.
- X-ray – Useful for viewing bones, lungs, and certain soft tissues.
- Ultrasound – Uses sound waves to examine organs and tissues; commonly used in pregnancy and abdominal conditions.
- CT (Computed Tomography) Scan – Combines X-rays from different angles to create cross-sectional images of the body.
- MRI (Magnetic Resonance Imaging) – Uses magnets and radio waves to produce detailed images of organs and tissues, especially the brain, spine, and joints.
- Mammography – A specialized X-ray used for breast cancer screening.
3. Endoscopic Procedures
Endoscopy involves inserting a thin, flexible tube with a camera into the body to view internal structures and collect tissue samples if needed. These procedures help diagnose and sometimes treat gastrointestinal, respiratory, or urinary issues.
- Upper GI Endoscopy – Examines the esophagus, stomach, and upper intestine.
- Colonoscopy – Inspects the colon and rectum; used for detecting polyps, bleeding, or cancer.
- Bronchoscopy – Used to view the airways and lungs.
- Cystoscopy – Checks the bladder and urethra.
- Laparoscopy – A surgical diagnostic tool used to examine organs in the abdomen or pelvis through small incisions.
4. Biopsy and Tissue Analysis
A biopsy involves removing a small sample of tissue or cells for examination under a microscope. It is often used to diagnose cancer, infections, and inflammatory diseases.
- Skin Biopsy – Removes skin tissue to diagnose rashes, infections, or skin cancer.
- Needle Biopsy – Uses a thin needle to extract tissue from organs like the liver, thyroid, or lymph nodes.
- Surgical Biopsy – Involves removing a larger tissue section, sometimes during surgery.
- Bone Marrow Biopsy – Assesses bone marrow function and helps diagnose blood disorders and cancers.
5. Genetic and Molecular Tests
These tests examine DNA, RNA, proteins, or chromosomes to detect genetic disorders, inherited diseases, or risks for certain cancers and conditions. They are also increasingly used in personalized medicine.
- Genetic Screening – Identifies inherited conditions like cystic fibrosis or BRCA mutations (breast/ovarian cancer risk).
- Pharmacogenetic Testing – Predicts how a patient may respond to specific medications.
- Newborn Screening – Detects rare metabolic or genetic disorders shortly after birth.
- Gene Panels or Whole Genome Sequencing – Comprehensive tests used in advanced diagnostics.
6. Functional and Performance Tests
These tests evaluate how well organs or systems are functioning in real-time, rather than just identifying abnormalities in structure or cells.
- Electrocardiogram (ECG/EKG) – Measures electrical activity of the heart to detect arrhythmias or damage.
- Stress Test – Assesses how the heart performs under physical exertion.
- Pulmonary Function Tests (PFTs) – Measure how well the lungs are working.
- EEG (Electroencephalogram) – Detects electrical activity in the brain, used for diagnosing epilepsy or sleep disorders.
- Eye and Hearing Tests – Evaluate sensory organ function and detect vision or hearing loss.
Common Diagnostic Test Procedures: Reference Table
Here is a list of common diagnostic procedures for your reference. It includes the name of the procedure, the type of sample collected, and a brief description of how the test is performed and its purpose.
| Test Procedure | Sample Tested | Procedure Description |
|---|---|---|
| Amniocentesis | Amniotic fluid | Fluid is withdrawn from the sac surrounding the fetus using a needle inserted through the abdomen. It helps detect fetal abnormalities, genetic disorders, and infections. |
| Blood Culture | Blood | A blood sample is taken and incubated to check for the presence of bacteria or fungi in the bloodstream. |
| Bone Marrow Biopsy | Bone marrow tissue | A needle is inserted into a large bone (usually the hip) to extract marrow for diagnosing blood disorders or cancers like leukemia. |
| Colonoscopy | No fluid sample; visual inspection | A flexible tube with a camera is inserted into the rectum to examine the colon and detect polyps, cancer, or inflammation. |
| Lumbar Puncture (Spinal Tap) | Cerebrospinal fluid (CSF) | CSF is collected via a needle inserted into the lower back to diagnose infections, bleeding, or neurological diseases. |
| Endoscopy | No fluid sample; visual and sometimes tissue biopsy | A thin tube with a camera is inserted through the mouth or rectum to inspect the digestive tract and collect biopsy samples. |
| Pleural Tap (Thoracentesis) | Pleural fluid | Fluid is withdrawn from the pleural space around the lungs to diagnose infection, malignancy, or heart failure. |
| Urinalysis | Urine | Urine is tested for the presence of proteins, glucose, red/white blood cells, or infection markers to evaluate kidney and metabolic health. |
| Electrocardiogram (ECG/EKG) | No sample; electrical signals from the heart | Electrodes placed on the chest record the electrical activity of the heart to detect arrhythmias or damage. |
| Pap Smear | Cervical cells | Cells are collected from the cervix and examined for pre-cancerous or cancerous changes caused by HPV. |
| Test Procedure | Sample Tested | Procedure Description |
|---|---|---|
| Amniocentesis | Fluid from the sac surrounding the fetus | Analysis of fluid, removed by a needle inserted through the abdominal wall, to detect an abnormality in the fetus |
| Arteriography (angiography) | Any artery in the body, commonly in the brain, heart, kidneys, aorta, or legs | X-ray study using radiopaque dye injected through a thin tube (catheter), which is threaded to the artery being studied, to detect and outline or highlight a blockage or defect in an artery |
| Audiometry | Ears | Assessment of the ability to hear and distinguish sounds at specific pitches and volumes using headphones |
| Auscultation | Heart | Listening with a stethoscope for abnormal heart sounds |
| Barium x-ray studies | Esophagus, stomach, intestine, or rectum | X-ray study to detect ulcers, tumors, or other abnormalities |
| Biopsy | Any tissue in the body | Removal and examination of a tissue sample under a microscope to check for cancer or another abnormality |
| Blood pressure measurement | Usually an arm | Test for high or low blood pressure, usually using an inflatable cuff wrapped around the arm |
| Spirometry | Lungs | Test of lung function that involves blowing into a measuring device |
| Stress testing | Heart | Test of heart function during exertion using a treadmill or other exercise machine and electrocardiography (if people cannot exercise, a drug is used to simulate exercise’s effects) |
| Thoracentesis | The space between the pleura, a two-layered membrane that covers the lungs and lines the chest wall (pleural space) | Removal of fluid from this space with a needle to detect abnormalities |
| Thoracoscopy | Lungs | Examination of the lung surfaces, pleura, and pleural space through a viewing tube |
| Tympanometry | Ears | Measurement of the resistance to pressure (impedance) in the middle ear using a device inserted in the ear and sound waves to help determine the cause of hearing loss |
| Ultrasonography (ultrasound scanning) | Any part of the body | Imaging using sound waves to detect structural or functional abnormalities |
| Urinalysis | Kidneys and urinary tract | Chemical analysis of a urine sample to detect protein, sugar, ketones, and blood cells |
| Venography | Veins | X-ray study using a radiopaque dye (similar to arteriography) to detect blockage of a vein |
| Blood tests | Usually a blood sample from an arm | Measurement of substances in the blood to evaluate organ function and to help diagnose and monitor various disorders |
| Bone marrow aspiration | Hipbone or breastbone | Removal of a bone marrow sample by a needle for examination under a microscope to check for abnormalities in blood cells |
| Bronchoscopy | Airways of the lungs | Direct examination with a viewing tube to check for a tumor or other abnormality |
| Cardiac catheterization | Heart | Study of heart function and structure using a catheter inserted into a blood vessel and threaded to the heart |
| Chorionic villus sampling | Placenta | Removal of a sample for examination under a microscope to check for abnormalities in the fetus |
| Chromosomal analysis | Blood | Examination under a microscope to detect a genetic disorder or to determine a fetus’s sex |
| Colonoscopy | Large intestine | Direct examination with a viewing tube to check for a tumor or other abnormality |
| Colposcopy | Cervix | Direct examination of the cervix with a magnifying lens |
| Computed tomography (CT) | Any part of the body | Computer-enhanced x-ray study to detect structural abnormalities |
| Cone biopsy | Cervix | Removal and examination of a cone-shaped piece of tissue, usually using a heated wire loop or a laser |
| Culture | A sample from any area of the body (usually a fluid such as blood or urine) | Growth and examination of microorganisms from the sample to identify infection with bacteria or fungi |
| Dilation and curettage (D and C) | Cervix and uterus | Examination of a sample under a microscope to check for abnormalities in the uterine lining using a small, sharp instrument (curet). |
| Dual x-ray absorptiometry (DEXA) | Skeleton, focusing on specific regions, usually the hip, spine, and wrist | Low-dose x-ray study to determine the thickness of bones |
| Echocardiography | Heart | Study of heart structure and function using sound waves |
| Electrocardiography (ECG) | Heart | Study of the heart’s electrical activity using electrodes attached to the arms, legs, and chest |
| Electroencephalography (EEG) | Brain | Study of the brain’s electrical function using electrodes attached to the scalp |
| Electromyography | Muscles | Recording of a muscle’s electrical activity using small needles inserted into the muscle |
| Electrophysiologic testing | Heart | Test to evaluate rhythm or electrical conduction abnormalities using a catheter inserted into a blood vessel and threaded to the heart |
| Endoscopic retrograde cholangiopancreatography (ERCP) | Biliary tract | X-ray study of the biliary tract done after injection of a radiopaque dye and using a flexible viewing tube |
| Endoscopy | Digestive tract | Direct examination of internal structures using a flexible viewing tube |
| Enzyme-linked immunosorbent assay (ELISA) | Usually blood | Test that involves mixing the sample of blood with substances that can trigger allergies (allergens) or with microorganisms to test for the presence of specific antibodies |
| Fluoroscopy | Digestive tract, heart, or lungs | A continuous x-ray study that enables a doctor to see the inside of an organ as it functions |
| Hysteroscopy | Uterus | Direct examination of the inside of the uterus with a flexible viewing tube |
| Intravenous urography | Kidneys and urinary tract | X-ray study of the kidneys and urinary tract after a radiopaque dye is injected into a vein (intravenously) |
| Joint aspiration | Joints, especially those of the shoulders, elbows, fingers, hips, knees, ankles, and toes | Removal and examination of fluid from the space within joints to check for blood cells, crystals formed from minerals, and microorganisms |
| Laparoscopy | Abdomen | Direct examination using a viewing tube inserted through an incision in the abdomen to diagnose and treat abnormalities in the abdomen |
| Magnetic resonance imaging (MRI) | Any part of the body | Imaging test using a strong magnetic field and radio waves to check for structural abnormalities |
| Mammography | Breasts | X-ray study to check for breast cancer |
| Mediastinoscopy | Chest | Direct examination of the area of the chest between the lungs using a viewing tube inserted through a small incision just above the breastbone |
| Myelography | Spinal column | Simple or computer-enhanced x-ray study of the spinal column after injection of a radiopaque dye |
| Nerve conduction study | Nerves | Test to determine how fast a nerve impulse travels using electrodes or needles inserted along the path of the nerve |
| Occult blood test | Large intestine | Test to detect blood in stool |
| Ophthalmoscopy | Eyes | Direct examination using a handheld device that shines light into the eye to detect abnormalities inside the eye |
| Papanicolaou (Pap) test | Cervix | Examination of cells scraped from the cervix under a microscope to detect cancer |
| Paracentesis | Abdomen | Insertion of a needle into the abdominal cavity to remove fluid for examination |
| Percutaneous transhepatic cholangiography | Liver and biliary tract | X-ray study of the liver and biliary tract after a radiopaque dye is injected into the liver |
| Positron emission tomography (PET) | Brain and heart | Imaging test using particles that release radiation (positrons) to detect abnormalities in function |
| Pulmonary function tests | Lungs | Tests to measure the lungs’ capacity to hold air, to move air in and out of the body, and to exchange oxygen and carbon dioxide as people blow into a measuring device |
| Radionuclide imaging | Many organs | Imaging test using particles that release radiation (radionuclides) to detect abnormalities in blood flow, structure, or function |
| Reflex tests | Tendons | Tests using a physical stimulus (such as a light tap) to detect abnormalities in nerve function |
| Retrograde urography | Bladder and ureters | X-ray study of the bladder and ureters after a radiopaque dye is inserted into the ureter |
| Sigmoidoscopy | Rectum and last portion of the large intestine | Direct examination using a viewing tube to detect tumors or other abnormalities |
| Skin allergy tests | Usually an arm or the back | Tests for allergies done by placing a solution containing a possible allergen on the skin, then pricking the skin with a needle |
| Spinal tap (lumbar puncture) | Spinal canal | Removal of spinal fluid, using a needle inserted into the hipbone, to check for abnormalities in spinal fluid |
| X-ray | Any part of the body | Imaging test using electromagnetic waves to create pictures of the inside of the body |
| X-ray angiography | Blood vessels | X-ray study using radiopaque dye injected into blood vessels to detect blockages or abnormalities |
| X-ray computed tomography (CT) | Any part of the body | Imaging test using x-rays and computer technology to create detailed cross-sectional images |
| X-ray dual energy x-ray absorptiometry (DEXA) | Bones | Low-dose x-ray study to determine bone mineral density and diagnose osteoporosis |
| X-ray fluoroscopy | Digestive tract, heart, or lungs | Continuous x-ray study that enables visualization of the inside of organs as they function |
| X-ray mammography | Breasts | X-ray study used to screen for breast cancer or detect abnormalities |
| X-ray projection radiography | Any part of the body | Basic x-ray imaging technique that produces 2D images |
| X-ray radiography | Any part of the body | Imaging technique that uses x-rays to create pictures of the inside of the body |
| X-ray voiding cystourethrography (VCUG) | Bladder and urethra | X-ray study using radiopaque dye to visualize the bladder and urethra during urination |
| X-ray xeroradiography | Any part of the body | X-ray imaging technique using dry development process to produce images |
| X-ray arthrography | Joints | X-ray study using contrast dye injected into a joint to visualize structures |
| X-ray hysterosalpingography | Uterus and fallopian tubes | X-ray study using contrast dye to visualize the uterus and fallopian tubes |
| X-ray intravenous pyelogram (IVP) | Kidneys and urinary tract | X-ray study using contrast dye to visualize the urinary system |
| X-ray myelography | Spinal column | X-ray study using contrast dye injected into the spinal canal to visualize the spinal cord and nerve roots |
| X-ray sialography | Salivary glands | X-ray study using contrast dye to visualize the salivary glands |
| X-ray small bowel series | Small intestine | X-ray study using contrast dye to visualize the small intestine |
| X-ray upper gastrointestinal (GI) series | Esophagus, stomach, and small intestine | X-ray study using contrast dye to visualize the upper GI tract |
| X-ray voiding urethrography | Urethra | X-ray study using contrast dye to visualize the urethra during urination |
| X-ray barium enema | Large intestine | X-ray study using contrast dye to visualize the colon and rectum |
| X-ray barium swallow | Esophagus | X-ray study using contrast dye to visualize the esophagus and swallowing function |
| X-ray barium follow-through | Small intestine | X-ray study using contrast dye to track the movement of barium through the small intestine |
| X-ray barium meal | Stomach | X-ray study using contrast dye to visualize the stomach |
| X-ray myelography | Spinal column | X-ray study using contrast dye injected into the spinal canal to visualize the spinal cord and nerve roots |
| X-ray upper gastrointestinal (GI) series | Esophagus, stomach, and small intestine | X-ray study using contrast dye to visualize the upper GI tract |
| Angioplasty | Blood vessels | Procedure to open narrowed or blocked blood vessels using a balloon-tipped catheter |
| Aortography | Aorta | X-ray study using contrast dye to visualize the aorta |
| Bronchography | Bronchi | X-ray study using contrast dye to visualize the bronchi |
| Cerebral angiography | Blood vessels in the brain | X-ray study using contrast dye to visualize blood vessels in the brain |
| Cholangiography | Biliary tract | X-ray study using contrast dye to visualize the biliary tract |
| Coronary angiography | Coronary arteries | X-ray study using contrast dye to visualize the coronary arteries |
| Cystography | Bladder | X-ray study using contrast dye to visualize the bladder |
| Enteroclysis | Small intestine | X-ray study using contrast dye to visualize the small intestine |
| Fistulography | Fistula | X-ray study using contrast dye to visualize a fistula |
| Gallbladder radionuclide scan | Gallbladder | Imaging test using radionuclides to visualize the gallbladder |
| Gastrointestinal motility studies | Gastrointestinal tract | Studies to assess the movement and function of the GI tract |
| Heart catheterization | Heart | Study of heart function and blood flow using a catheter inserted into a blood vessel |
| Hysterosalpingography | Uterus and fallopian tubes | X-ray study using contrast dye to visualize the uterus and fallopian tubes |
| Intravenous pyelogram (IVP) | Kidneys and urinary tract | X-ray study using contrast dye to visualize the urinary system |
| Lymphangiography | Lymphatic vessels | X-ray study using contrast dye to visualize the lymphatic vessels |
| Magnetic resonance angiography (MRA) | Blood vessels | Imaging test using magnetic resonance imaging to visualize blood vessels |
| Magnetic resonance cholangiopancreatography (MRCP) | Biliary and pancreatic ducts | Imaging test using magnetic resonance imaging to visualize the biliary and pancreatic ducts |
| Myelography | Spinal column | X-ray study using contrast dye injected into the spinal canal to visualize the spinal cord and nerve roots |
| Phlebography | Veins | X-ray study using contrast dye to visualize the veins |
| Pulmonary angiography | Pulmonary arteries | X-ray study using contrast dye to visualize the pulmonary arteries |
| Radionuclide angiography | Heart and blood vessels | Imaging test using radionuclides to visualize heart and blood vessel function |
| Renal angiography | Kidneys and blood vessels | X-ray study using contrast dye to visualize the kidneys and blood vessels |
| Sialography | Salivary glands | X-ray study using contrast dye to visualize the salivary glands |
| Small bowel enteroclysis | Small intestine | X-ray study using contrast dye to visualize the small intestine |
| Ventriculography | Heart ventricles | X-ray study using contrast dye to visualize the heart ventricles |
| Vessel Doppler ultrasound | Blood vessels | Ultrasound test to visualize blood flow in the blood vessels |
| Visual acuity test | Eyes | Test to measure the clarity of vision using an eye chart |
| Visual field test | Eyes | Test to measure the extent of peripheral vision |
| Vitamin B12 assay | Blood | Blood test to measure vitamin B12 levels |
| Vitamin K assay | Blood | Blood test to measure vitamin K levels |
| Von Willebrand factor antigen | Blood | Blood test to measure von Willebrand factor levels |
| Von Willebrand factor multimers | Blood | Blood test to evaluate the size distribution of von Willebrand factor multimers |
| Von Willebrand factor ristocetin cofactor activity | Blood | Blood test to measure the ristocetin cofactor activity of von Willebrand factor |
| Von Willebrand factor collagen binding assay | Blood | Blood test to measure the collagen binding activity of von Willebrand factor |
| Von Willebrand factor activity | Blood | Blood test to measure the activity of von Willebrand factor |
| White blood cell count (WBC count) | Blood | Blood test to count the number of white blood cells |
| White blood cell differential | Blood | Blood test to identify and count the different types of white blood cells |
| X-ray | Any part of the body | Imaging test using electromagnetic radiation to visualize structures inside the body |
| X-ray computed tomography (CT scan) | Any part of the body | Imaging test using x-rays and computer technology to create detailed cross-sectional images of the body |
| X-ray, chest | Chest | X-ray study of the chest to check for abnormalities in the lungs and other structures |
| X-ray, skeletal survey | Skeleton | X-ray study of the entire skeleton to detect abnormalities |
| Arterial blood gases | Blood from an artery | Measurement of the levels of oxygen, carbon dioxide, and other gases in the blood |
| Urine culture and sensitivity | Urine | Growth of microorganisms from a urine sample to identify the specific bacteria causing an infection and to determine the most effective antibiotic treatment |
| Urine protein test | Urine | Measurement of the amount of protein in the urine to detect kidney damage or other medical conditions |
| Urodynamic testing | Bladder and urethra | Assessment of the bladder's ability to hold and release urine and the pressure within the bladder and urethra during urination |
| Vaginal wet mount | Vaginal discharge | Microscopic examination of vaginal discharge to diagnose infections and other vaginal conditions |
| Vitamin B12 level | Blood | Measurement of vitamin B12 levels in the blood to assess vitamin deficiency or other medical conditions |
| Vitamin D level | Blood | Measurement of vitamin D levels in the blood to assess bone health and overall well-being |
| Voiding cystourethrogram (VCUG) | Bladder and urethra | X-ray study of the bladder and urethra during urination to detect abnormalities |
| Von Willebrand factor (vWF) testing | Blood | Measurement of vWF levels and activity to diagnose bleeding disorders |
| West Nile virus testing | Blood or cerebrospinal fluid | Detection of West Nile virus in blood or cerebrospinal fluid to diagnose infection |
Know the Blood Tests Reference Range
Imaging: Seeing Inside the Body
Medical imaging provides visual representations of the inside of the body, either entirely or focused on specific areas. It plays a vital role in diagnosing diseases, evaluating their severity, and guiding treatment and follow-up care.
Most imaging procedures are noninvasive, painless, and generally safe. They don’t require cutting the skin or inserting tools into the body (though a few specialized procedures may involve minor intervention).
Imaging techniques use various energy forms:
- Radiation-based: X-rays, CT (Computed Tomography), PET (Positron Emission Tomography), angiography, and radionuclide scanning.
- Sound waves: Ultrasonography (Ultrasound) is safe, commonly used in pregnancy and abdominal evaluations.
- Magnetic fields: MRI (Magnetic Resonance Imaging) offers detailed images without radiation exposure.
Sometimes, contrast agents (special dyes) are swallowed, injected, or inserted to make certain tissues or blood vessels more visible in the images. Doctors will inform you about any allergies or risks before using contrast.
Endoscopy: A Direct Look Inside the Body
Endoscopy allows doctors to look directly into organs and cavities using a thin, flexible tube called an endoscope, which has a camera and light source. Images are shown on a monitor for clarity and precision.
Many endoscopic procedures are done through natural body openings, such as:
- Nose: For laryngoscopy (voice box) or bronchoscopy (lungs).
- Mouth: For esophagoscopy (esophagus), gastroscopy (stomach), and upper GI endoscopy (small intestine).
- Anus: For colonoscopy (large intestine and rectum).
- Urethra: For cystoscopy (bladder).
- Vagina: For hysteroscopy (uterus).
If internal access isn't possible via natural openings, a small incision is made for:
- Arthroscopy: Joints
- Laparoscopy: Abdomen
- Mediastinoscopy: Chest area between lungs
- Thoracoscopy: Lungs and pleura (chest lining)
Many endoscopes also have channels that allow doctors to insert instruments for procedures such as biopsies or removing abnormal tissues.
Measuring Body Functions
Some tests assess how well your organs are functioning by recording their activity. These are vital for diagnosing functional disorders, even when anatomy looks normal in imaging tests.
- Electrocardiography (ECG/EKG): Measures the heart’s electrical activity to detect arrhythmias, heart attacks, or other heart conditions.
- Electroencephalography (EEG): Tracks brain wave patterns, commonly used in epilepsy or sleep disorder diagnosis.
- Pulmonary Function Tests (PFTs): Evaluate how well your lungs inhale, exhale, and exchange gases.
Biopsy: Examining Tissue at the Cellular Level
When imaging or symptoms suggest a suspicious area, a biopsy is often needed. This involves removing a small sample of tissue to be examined under a microscope.
Biopsies help diagnose:
- Inflammatory conditions
- Infections
- Pre-cancerous or cancerous cells
Genetic Testing: Insights from Your DNA
Genetic analysis involves studying your chromosomes, genes, or DNA to detect inherited or spontaneous changes that may lead to disease. This powerful diagnostic tool can:
- During pregnancy: Detect genetic abnormalities in the fetus.
- In children: Diagnose inherited disorders early for timely treatment.
- In adults: Predict risk for future illnesses or determine the likelihood of passing on a condition.
Modern genetic tests are becoming more accurate and faster with technologies like gene sequencing and mutation detection.
Navigating the Risks and Rewards of Medical Testing
While medical tests are crucial for accurate diagnosis and treatment planning, they are not without risks. Potential concerns include:
- Physical risks: Discomfort, bleeding, or rare complications during or after the test.
- False positives/negatives: May lead to unnecessary follow-up tests, emotional stress, or delayed treatment.
- Cost and accessibility: Some tests can be expensive or require specialized facilities.
Doctors always weigh the potential benefits of the test against its risks and only recommend those that are truly necessary.
Understanding Test Results
Most test results are compared against a “normal range,” which represents typical values seen in healthy individuals. However, these ranges can vary depending on:
- Age and sex of the patient
- The specific method or equipment used by the lab
- Individual health conditions or medications
Therefore, your doctor interprets the results in the context of your symptoms, medical history, and the lab’s reference values. Never self-interpret reports—always consult your healthcare provider for accurate guidance.
Disclaimer: This information is for educational purposes only. The intention is to provide assistance to patients and caregivers. The information provided here is referenced from MSD Manuals. However, it is important to consult your doctor for accurate medical advice and diagnosis.