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Lab Tests FAQ

What is a medical laboratory or lab?

A laboratory (lab) is any facility that does laboratory testing on specimens derived from humans to give information for the diagnosis,prevention, treatment of disease, or assessment of health. The Clinical Laboratory Improvement Amendments of 1988 (CLIA ’88) are federal guidelines for the regulation of laboratory testing to ensure the accuracy, reliability and timeliness of patient test results regardless of where the test was performed. The Centers for Medicare & Medicaid Services (CMS) oversees the implementation of CLIA and is responsible for the oversight of these regulations in laboratory settings. Laboratories are required to be inspected and re-accredited every two years.

What are medical lab tests?

Lab tests are examinations performed on blood, body fluids, tissues, and other substances in order to determine what is normal or what is abnormal for you as a patient.

Why are medical lab tests performed?

It has been estimated that 60% to 70% of diagnoses and/or treatments are based on lab tests. Your doctor may request one or many lab tests depending on your condition. Your doctor uses lab results to identify changes in your health condition, diagnose a disease or condition, plan your treatment, evaluate your response to a treatment, or monitor the course of a disease over time.

Who can order medical lab tests?

Only your doctor or other authorized ordering healthcare provider can order lab tests. Patients cannot order their own tests.

Do I have to fast before my medical lab tests?

Fast means to not eat or drink anything for approximately 12 hours prior to the test. Fasting means you should not eat or drink any liquids except for water. You do not have to fast unless your doctor has ordered a “fasting” test. Two common tests that are generally done fasting are glucose and lipid panel.

Can I take my medications before I have medical lab tests?

Please ask your physician before having laboratory specimens collected.

Why do you need more than one tube of blood?

Different tests often require separate tubes of blood, some with special additives. We strive to draw the minimum amount of blood required for the tests your physician has ordered.

Who performs the testing on laboratory specimens?

Most lab testing is performed by certified, college degreed medical technologists or medical technicians or by pathologists who are board certified physicians with licenses to practice medicine. Testing personnel must satisfy rigid accreditation standards set forth by the federal Clinical Laboratory Improvement Amendments of 1988 (CLIA ’88).

When will my test results be available?

Most test results are available within a week. Many test results are available within 4 to 24 hours. Multiple factors affect how soon test results are available. Tissue specimens, such as a tumor that is being analyzed for cancer, may take days to complete due to the numerous, complex steps that must be performed to process the specimen and requests for additional studies. Specimens submitted to be tested for bacteria or other microorganisms are cultured so the organisms can grow to a level where it can be seen. Routine cultures (e.g. strep throat or urinary tract infections) take a minimum of 24-48 hours to grow; other cultures (e.g. tuberculosis) may take up to 21 days to grow. Many times, positive cultures require additional steps such as organism identification and susceptibility to antibiotics. Other specialized tests may be sent to an outside reference laboratory; this may lengthen the turnaround time.

Can I receive a copy of my test results?

By law, lab results are reported only to the ordering physician or other authorized ordering healthcare provider. Patients are encouraged to obtain their laboratory test results from their doctor. In some instances, hospital patients may contact the hospital Release of Information Department.

Can you tell me what the lab results mean?

Lab personnel are not allowed to interpret test results for the patient. Many tests have more than one purpose. We cannot tell you why you are having the test or what the results mean. We do not know your medical history and we are not doctors. Please speak with your doctor. Lab results are only a part of the total diagnostic picture of your health. Your doctor makes decisions based on your clinical symptoms, laboratory results, history and physical, and other diagnostic tests such as imaging studies.

I am a hospital inpatient. Why are my blood specimens collected so early in the day?

Blood samples are collected primarily during the early morning hours beginning at 3a.m. and continuing until 6:30a.m. so that most of the laboratory results are available for your physician by 7 a.m. It is important to have the results by 7a.m. for physicians to make decisions about the patient’s condition and treatment for the day. Blood specimens can be collected throughout the day depending on the patient’s condition or treatment. In some instances, blood must be obtained at timed intervals in order to monitor specific conditions like cardiac enzymes for cardiac problems or to determine a diagnosis like a glucose tolerance test for diabetes.