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Glossary of Terms


ACC - American College of Cardiology is a nonprofit medical association of cardiovascular specialists who meet its qualifications. Education is a core component of the College, which also states it is active in the formulation of health policy and a supporter of cardiovascular research.

ACE-I - Angiotensin-converting enzyme (ACE) inhibitors help relax blood vessels. ACE inhibitors prevent an enzyme in your body from producing angiotensin II, a substance in your body that affects your cardiovascular system by narrowing your blood vessels and releasing hormones that can raise your blood pressure. This narrowing can cause high blood pressure and force your heart to work harder.

Academic Research Organization (ARO) - An academic institution contracted by a sponsor to perform one or more research-related functions.

Acute coronary syndromes - A range of conditions that reflect reduced or absent blood flow to the heart muscle; includes angina (stable and unstable) and heart attack

ACS - Acute coronary syndrome is a term used for any condition brought on by sudden, reduced blood flow to the heart. Acute coronary syndrome symptoms may include the type of chest pressure that you feel during a heart attack, or pressure in your chest while you're at rest or doing light physical activity (unstable angina).

Adjudication - The use of standard, objective criteria to classify events such as stroke or heart attack.

ADL - Activities of Daily Living - The tasks of everyday life. Basic ADL’s are eating, dressing, getting into or out of a bed or chair, taking a bath or shower and using a toilet.

Adverse Event (AE) -Also known as side effects, adverse reactions include any undesired actions or effects of the experimental drug or treatment. Experimental treatments must be evaluated for both immediate and long-term side effects.

AHA - The American Heart Association is the nation’s oldest, largest voluntary organization devoted to fighting cardiovascular diseases and stroke.

ALT - The alanine aminotransferase (ALT) test is typically used to detect liver injury. It is often ordered in conjunction with aspartate aminotransferase (AST) or as part of a liver panel to screen for and/or help diagnose liver disease.

ALP - The alkaline phosphatase test (ALP) is used to help detect liver disease or bone disorders.

Approval - A drug, device or biologic must be approved by a country’s regulatory agency before it can be marketed. The approval process involves several steps including pre-clinical (animal) studies, clinical trials for safety and efficacy, filing of a New Drug Application (NDA) in the United States or Marketing Authorization Application (MAA) in Europe by the manufacturer, regulatory agency review of the application, and agency approval/rejection of application.

Arm - Any of the treatment groups in a clinical trial. Most randomized trials have two “arms,” but some have three “arms,” or even more.

AST - Aspartate aminotransferase (AST) is usually used to detect liver damage. It is often ordered in conjunction with another liver enzyme, alanine aminotransferase (ALT), or as part of a liver panel to screen for and/or help diagnose liver disorders.

Baseline - Baseline information is gathered at the beginning of a study from which variations found in the study are measured. Baseline can also be described as a known value or quantity with which an unknown is compared when measured or assessed. Safety and efficacy of a drug are often determined by monitoring changes from the baseline values.

Bias - When a point of view prevents impartial judgment on issues relating to the subject of that point of view. In clinical studies, bias is controlled by blinding and randomization.

Blind, Blinded or Blinding - A clinical trial is “blinded” if the participants are unaware on whether they are in the experimental or control arm of the study. Blinding may also be extended to the investigators so that their patient observations are less likely to be biased by their awareness of the treatment the patient is receiving.

Bpm – Heart rate, also known as pulse, is the number of times a person's heart beats per minute.

BUN - The blood urea nitrogen or BUN test is primarily used, along with the creatinine test, to evaluate kidney function in a wide range of circumstances, to help diagnose kidney disease, and to monitor people with acute or chronic kidney dysfunction or failure.

CABG - Coronary bypass surgery is a procedure that restores blood flow to your heart muscle by diverting the flow of blood around a section of a blocked artery in your heart. Coronary bypass surgery uses a healthy blood vessel taken from your leg, arm, chest or abdomen and connects it to the other arteries in your heart so that blood is bypassed around the diseased or blocked area.

CAD - Coronary artery disease develops when your coronary arteries — the major blood vessels that supply your heart with blood, oxygen and nutrients — become damaged or diseased. Cholesterol-containing deposits (plaque) in your arteries and inflammation are usually to blame for coronary artery disease.

CATH - Cardiac catheterization is a procedure used to diagnose and treat cardiovascular conditions. During cardiac catheterization, a long thin tube called a catheter is inserted in an artery or vein in your groin, neck or arm and threaded through your blood vessels to your heart. Using this catheter, doctors can then do diagnostic tests as part of a cardiac catheterization. Some heart disease treatments, such as coronary angioplasty, also are done using cardiac catheterization.

CBC - A complete blood count (CBC) is a blood test used to evaluate your overall health and detect a wide range of disorders, including anemia, infection and leukemia. A complete blood count test measures several components and features of your blood, including:

  • Red blood cells, which carry oxygen
  • White blood cells, which fight infection
  • Hemoglobin, the oxygen-carrying protein in red blood cells
  • Hematocrit, the proportion of red blood cells to the fluid component, or plasma, in your blood
  • Platelets, which help with blood clotting

CCTA - A computerized tomography coronary angiogram is an imaging test that looks at the arteries that supply your heart with blood. Unlike traditional coronary angiograms, CT angiograms don't use a catheter threaded through your blood vessels to your heart.

CK - A creatine kinase (CK) test may be used to detect inflammation of muscles (myositis) or serious muscle damage.

CK – MB - A CK-MB test may be used as a follow-up test to an elevated CK in order to determine whether the increase is due to heart damage or skeletal muscle damage. The test is most likely to be ordered if a person has chest pain or if a person's diagnosis is unclear, such as if a person has nonspecific symptoms like shortness of breath, extreme fatigue, dizziness, or nausea.

Clinical Research - medical research that involves people to test new treatments and therapies.

Cmax - is a term that refers to the maximum (or peak) serum concentration that a drug achieves in a specified compartment or test area of the body after the drug has been administrated and prior to the administration of a second dose.

CMR - Magnetic resonance imaging (MRI) is a safe, noninvasive test that creates detailed pictures of your organs and tissues. Cardiac MRI creates both still and moving pictures of your heart and major blood vessels. Doctors use cardiac MRI to get pictures of the beating heart and to look at its structure and function.

CNS - The central nervous system is that part of the nervous system that consists of the brain and spinal cord.

CPT-II - is a task-oriented computerized assessment of attention-related problems in individuals aged 8 years and older.

CMAPs - Compound Muscle Action Potentials is an electromyography investigation (electrical study of muscle function).

Confidentiality Regarding Trial Participants - Refers to maintaining the confidentiality of trial participants including their personal identity and all personal medical information. The trial participants' consent to the use of records for data verification purposes must be obtained prior to the trial. The Informed Consent Document will explain how personal health information and study data will be used in accordance with pertinent data protection laws and regulations.

Contraindication - A specific circumstance in which the use of certain treatments are not allowed usually because they could be harmful or fatal.

Controlled Trials - A control is a standard against which experimental observations may be evaluated. In a controlled clinical trial, one group of participants is given an experimental drug, while another group (i.e., the control group) is given either a standard treatment for the disease or a placebo.

Crossover Trial - A clinical trial in which all participants receive both treatments, but at different times. At a predetermined point in the study, one group is switched from the experimental treatment to the control treatment (standard treatment), and the other group is switched from the control to the experimental treatment.

CrCl - The creatinine clearance test helps provide information about how well the kidneys are working. The test compares the creatinine level in urine with the creatinine level in blood.

CRP C - The level of C-reactive protein (CRP), which can be measured in your blood, increases when there's inflammation in your body.

CRPS - Complex regional pain syndrome (CRPS) is a chronic pain condition most often affecting one of the limbs (arms, legs, hands, or feet), usually after an injury or trauma to that limb.

C-SSRS - Columbia-Suicide Severity Rating Scale is a scale used to determine the presence of suicidal ideation or behavior.

CT - Computerized tomography (CT scan) combines a series of X-ray views taken from many different angles and computer processing to create cross-sectional images of the bones and soft tissues inside your body.

CV – Cardiovascular- dealing with the heart and blood vessels.

CVD - Cardiovascular Disease or heart disease describes a range of conditions that affect your heart. Diseases under the heart disease umbrella include blood vessel diseases, such as coronary artery disease; heart rhythm problems (arrhythmias); and heart defects you're born with (congenital heart defects), among others.

DBP - Diastolic Blood Pressure is the bottom number and indicates the pressure in the arteries when the heart rests between beats.

DNA - deoxyribonucleic acid is the hereditary material in humans and almost all other organisms.

Data Safety Monitoring Board (DSMB) - A committee, independent of the sponsor, composed of clinical research experts that review trial data while a clinical trial is in progress to ensure that participants are not exposed to undue risk. A DSMB may recommend that a trial be stopped if there are safety concerns or if the trial objectives have been achieved and further continuing the study would not benefit the patients.

Data Safety Monitoring PLAN (DSMP) - This plan is meant to assure that each clinical trial has a system for appropriate oversight and monitoring of the conduct of the trial. This oversight ensures the safety of the participants and the validity and integrity of the data.

Demographic Data - The characteristics of participant group or populations. This could include data on race, age, sex and medical history, all of which can be relevant to the clinical trial study findings.

Device - An instrument, apparatus, implement, machine, contrivance, implant, in vitro reagent, or other similar or related article, including any component, part or accessory, that is used to diagnose, cure, treat, or prevent disease. A device does not achieve its intended purpose through chemical action or metabolism in the body.

Diagnostic Trials - Refers to trials that are conducted to find better tests or procedures for diagnosing a particular disease or condition. Diagnostic trials usually include people who have signs or symptoms of the disease or condition being studied.

Dose-Ranging Study - A clinical trial in which two or more doses of an agent (such as a drug) are tested against each other to determine which dose works best and is least harmful.

Double-Blind Study - A clinical trial design in which neither the participating individuals nor the study staff knows which participants are receiving the experimental drug and which are receiving a placebo or another therapy). Double-blind trials are thought to produce objective results, since the knowledge, expectations and biases of the doctor and the participant about the experimental drug or treatment do not affect the outcome.

Drug-Drug Interaction - A modification of the effect of a drug when administered with another drug. The effect may be an increase or a decrease in the action of either substance, or it may be an adverse effect that is not normally associated with either drug.

DVT – Deep Vein Thrombosis is the formation of a blood clot in a deep vein, usually in a calf or thigh muscle.

Early termination or withdrawal - Any subject who is randomized and discontinues from the study prior to completing the study requirements.

ECAP - Evoked Compound Action Potential is a neural response to spinal cord stimulation.

ECG - Electrocardiogram (EKG or ECG) is a test that checks for problems with the electrical activity of your heart. An EKG translates the heart's electrical activity into line tracings on paper. The spikes and dips in the line tracings are called waves.

EEG – Electroencephalograph is a test which records electrical impulses from the nerves in the head. “Electro” refers to the electrical impulses sent from one nerve cell to another. These impulses are the way nerves talk to each other and get information from the brain to the rest of the body. “Encephalo” refers to the head, and “gram” refers to the printed record.

Effectiveness - Whether a drug achieves its desired effect in the real world.

Efficacy - (Of a drug or treatment) the ability of a drug or treatment to produce a beneficial result. A drug demonstrates efficacy if it is effective at the dose tested against the illness for which it is prescribed.

eGFR - The eGFR is used to screen for and detect early kidney damage and to monitor kidney status. It is performed by ordering a creatinine test and calculating the estimated glomerular filtration rate.

Eligibility Criteria - Summary criteria for participant selection; includes inclusion and exclusion criteria.

Empirical - Based on observation or experience, not experimental data.

Epidemiology - The branch of medical science that deals with the study of incidence, distribution and control of a disease in a population.

EMG - Electromyography is a diagnostic procedure to assess the health of muscles and the nerve cells that control them (motor neurons).

Endpoint - The endpoint is an event or outcome that may be measured objectively to determine whether the intervention being studied is beneficial.

EQ-5D - is a standardized instrument for use as a measure of health outcome.

ESR - Erythrocyte Sedimentation Rate is the rate at which red blood cells sediment in a period of one hour. It is a common hematology test, and is a non-specific measure of inflammation.

ETS - External Trial System, the complete system for spinal cord stimulation.

First-In-Human/Man Study - A clinical trial where a medical procedure or medicinal product, previously developed and assessed through laboratory model or animal testing, or through mathematical modeling is tested on human subjects for the first time.

GCS - The Glasgow Coma Scale is the most common scoring system used to describe the level of consciousness in a person following a traumatic brain injury.

Generic Drugs - A medicine with the same active ingredient, but not necessarily the same inactive ingredients, as a brand-name drug. A generic drug may be marketed only after the original drug's patent has expired.

GOAT - Galveston Orientation and Amnesia Test is a measure of attention and orientation, especially to see if a patient has recovered from post-traumatic amnesia (PTA) after a traumatic brain injury.

GOS-E - Glasgow Outcome Scale-Extended is a questionnaire used to define broad outcome categories for people who sustain acute brain damage from head injury or non-traumatic brain insults. The scale reflects disability and handicap rather than impairment.

HbA1c - The hemoglobin A1C test is a blood test that provides information about a person’s average levels of blood glucose, also called blood sugar, over the past 3 months. The A1C test is sometimes called the hemoglobin A1c, HbA1c, or glycohemoglobin test. The A1C test is the primary test used for diabetes management

Hct – Hematocrit is the proportion of your total blood volume that is composed of red blood cells. A hematocrit (Hct) test indicates whether you have too few or too many red blood cells.

HDL-C - High-density lipoprotein cholesterol is the well-behaved "good cholesterol." It removes harmful bad cholesterol from the bloodstream. High HDL levels reduce the risk for heart disease -- but low levels increase the risk.

Hgb - Hemoglobin is the protein in your red blood cells that carries oxygen.

HIPAA - The Health Insurance Portability and Accountability Act of 1996 (HIPAA) established national standards for electronic health care transactions and national identifiers for providers, health plans, and employers. It also addresses the security and privacy of health data. All clinical trial data and activities performed by covered entities must comply with HIPAA regulations.

ICP - Intracranial pressure is the pressure inside the skull and in the brain tissue and cerebrospinal fluid (CSF).

ICU - Intensive care unit is a unit in the hospital where seriously ill patients are cared for by specially trained staff.

INR - International Normalized Ratio which provides some information about a person’s blood’s tendency to clot (which is often described as how “thin” or “thick” their blood is).

Investigational Product (IP) - Pharmaceutical form of an active ingredient or placebo, comparator, vaccine, biological product, or device being tested or used as a reference in a clinical trial, including a product with a marketing authorization, when used or assembled in a way different from the approved form, or for an unapproved indication, or used to gain further information about an approved use.

IPG - Implantable Pulse Generator is a battery powered electronic device that generates electric pulses that can be used by spinal cord stimulation devices to control pain. It is one of the items in a spinal cord stimulation system.

Intent To Treat - Analysis of clinical trial results that includes all data from participants in the groups to which they were randomized even if they never received the treatment.

Intervention Name - The generic name of the experimental treatment being studied.

Interventions - Primary experimental treatments being studied. Types of treatments may include drug, gene transfer, vaccine, behavior, device, or procedure.

Investigational New Drug Application (IND) - The petition through which a drug sponsor requests the FDA to allow human testing of a new drug, antibiotic drug, or biological drug in a clinical investigation. This includes an application for a biological product used in vitro for diagnostic purposes.

IN VIVO - Testing or action inside an organism, such as a human subject or patient.

IN VITRO - Testing or action outside an organism (e.g. inside a test tube or culture dish.)

i.v. - Intravenous simply means "within vein". It is the infusion of liquid substances directly into a vein.

KOOS - Knee Injury and Osteoarthritis Outcome Score is a questionnaire developed as an instrument to assess a patient’s opinion about their knee and associated problems.

LAR - Legally authorized representative is an individual or judicial or other body authorized under applicable law to consent on behalf of a prospective subject to the subject's participation in the procedures involved in the research.

LDL - Low-density lipoprotein are one of the five groups of lipoproteins. Lipoproteins transfer fats through the bloodstream, then the intracellular (water) to all cells around the body

MAP - Mean arterial pressure is a term used in medicine to describe an average blood pressure in an individual.

MF – Microfracture is a surgical procedure in which an instrument is used to poke holes in the bone surrounding the knee. These tiny punctures are meant to stimulate blood flow to repair torn cartilage in the area. This has to be done because the human body doesn’t regenerate cartilage on its own. So the blood brought in by the microfracture surgery can ideally latch on to the injured area and help protect the bone.

MI - Myocardial Infarction, commonly known as a heart attack, occurs when blood flow stops to part of the heart causing damage to the heart muscle.

MPAI-4 - Mayo-Portland Adaptability Inventory – (4th Edition) is and evaluation to assist in the clinical evaluation of people during the post-acute (post hospital) period following acquired brain injury (ABI).

MRI - Magnetic Resonance Imaging is a technique that uses a magnetic field and radio waves to create detailed images of the organs and tissues within your body.

MS - Multiple sclerosis is an unpredictable, often disabling disease of the central nervous system that disrupts the flow of information within the brain, and between the brain and body.

Multicenter Trial - Clinical trial conducted according to a single protocol but at more than one site, and, therefore, carried out by more than one investigator.

NAART - North American Adult Reading Test is a quickly administered index that is widely used to estimate verbal intellectual ability.

NCS - Non-convulsive seizure is an episode when a patient has prolonged absence and atypical absence events, lasting a half-hour, an hour, or days.

NDI - National Death Index is a centralized database of death record information on file in state vital statistics offices.

National Institutes Of Health (NIH) - Agency within the Department of Health and Human Services that funds research, conducts studies, and funds multicenter national studies.

New Drug Application (NDA) - An application submitted by a sponsor to the FDA for approval to market a new drug (a new, non-biological molecular entity) for human use in interstate commerce in the United States.

NRS - Numerical Rating Scale is a pain scale that measures a patient's pain intensity or other features. Pain scales are based on self-report, observational (behavioral), or physiological data.

Observational Study - An epidemiologic study that does not involve any intervention, experimental or otherwise. Such a study may be one in which nature is allowed to take its course, with changes in one characteristic being studied in relation to changes in other characteristics. Analytical epidemiologic methods, such as case-control and cohort study designs, are properly called observational epidemiology because the investigator is observing without intervention other than to record, classify, count, and statistically analyze results.

Outcomes Trial/Study - An outcomes trial evaluates the effect of a treatment on patients. Treatments may include medications or other therapies and outcomes may include changes in disease status, morbidity or mortality.

Parallel Study - A parallel designed clinical trial compares the results of a treatment on two separate groups of patients. The sample size calculated for a parallel design can be used for any study where two groups are being compared.

PE - Pulmonary embolism, or PE, is a sudden blockage in a lung artery. The blockage usually is caused by a blood clot that travels to the lung from a vein in the leg.

Pharmacology - The study of how drugs interact with living organisms to produce a change in function. Pharmacology deals with how drugs interact within biological systems to affect function.

Pharmacokinetics - The processes (in a living organism) of absorption, distribution, metabolism, and excretion of a drug or vaccine.

Pharmacovigilance - The science of collecting, monitoring, researching, assessing and evaluating information from healthcare providers and patients on the adverse effects of medications, biological products, herbalism and traditional medicines with a view to identify new information about hazards associated with medicines and preventing harm to patients.

Prospective Study - A prospective study identifies subjects, applies a treatment and follows them over time to measure their progress/outcomes relative to a predetermined set of criteria or endpoints.

POMS - Profile of Mood States is a psychological rating scale used to assess transient, distinct mood states.

PTSD - Post traumatic stress disorder once called shell shock or battle fatigue syndrome, is a serious condition that can develop after a person has experienced or witnessed a traumatic or terrifying event in which serious physical harm occurred or was threatened.

RA - Rheumatoid arthritis is a chronic inflammatory disorder that typically affects the small joints in your hands and feet. Unlike the wear-and-tear damage of osteoarthritis, rheumatoid arthritis affects the lining of your joints, causing a painful swelling that can eventually result in bone erosion and joint deformity.

RBANS - Repeatable Battery for the Assessment of Neuropsychological Status is a neuropsychological assessment. It consists of ten subtests which give five scores, one for each of the five domains tested (immediate memory, visuospatial/constructional, language, attention, delayed memory).

Rescue Medication - A quick-relief or fast-acting medication patients in clinical trials may be given besides the investigational drug or control that can alleviate symptoms due to disease or lack of efficacy of the study treatment. It acts quickly to stop symptoms, but the effects are not long lasting.

Retrospective Study - A study in which investigators select groups of patients that have already been treated and analyze data from the events experienced by these patients. These studies are subject to bias because investigators can select patient groups with known outcomes.

RPSQ - Rivermead Post-concussion Symptoms Questionnaire is a questionnaire that can be administered to someone who sustains a concussion or other form of traumatic brain injury to measure the severity of symptoms.

SBP - Systolic blood pressure. When your heart beats, it contracts and pushes blood through the arteries to the rest of the body. This force creates pressure on the arteries. This is called systolic blood pressure.

Screen failure - Only a subject who has signed an informed consent form and is not randomized due to failing inclusion or exclusion criteria will be designated a screen failure.

SCS - Spinal Cord Stimulation is a procedure that uses an electrical current to treat chronic pain. Peripheral nerve stimulation (PNS) and spinal cord stimulation (SCS) are two types of electrical nerve stimulation. In either, a small pulse generator sends electrical pulses to the nerves (in peripheral nerve stimulation) or to the spinal cord (in spinal cord stimulation). These pulses interfere with the nerve impulses that make you feel pain.

SF-MPQ-2 - Short Form-McGill Pain questionnaire provides a comprehensive measure of pain symptoms of both neuropathic and non-neuropathic pain conditions

SF-36 - Short Form – 36 is a patient-reported survey of patient health.

Stimulation side effects - Overstimulation or other unwanted changes in stimulation.

TBI - Traumatic brain injury is a complex injury with a broad spectrum of symptoms and disabilities.

TIA - Transient Ischemic Attack is like a stroke, producing similar symptoms, but usually lasting only a few minutes and causing no permanent damage. Often called a mini-stroke, a transient ischemic attack may be a warning.

TMT - Trail making test is a neuropsychological test of visual attention and task switching.

TSH - Thyroid stimulating hormone (also known as thyrotropin, TSH, or hTSH for human TSH) is a pituitary hormone that stimulates the thyroid gland to produce thyroxine (T4), and then triiodothyronine (T3) which stimulates the metabolism of almost every tissue in the body.

UADE - Unanticipated Adverse Device Event is “any serious effect on health or safety or any life-threatening problem or death caused by, or associated with, a device, if that effect, problem, or death was not previously identified in nature, severity, or degree of incidence in the investigational plan or application (including a supplementary plan or application), or any other unanticipated serious problem associated with a device that relates to the rights, safety, or welfare of subjects”.

VAS - Visual Analogue Scale is a numerical scale used to rate pain.

WAIS-R - Wechsler Adult Intelligence Scale-Revised is a test designed to measure intelligence in adults and older adolescents.

WBC - White blood cell count The WBC is usually measured as part of the CBC (complete blood count). White blood cells are the infection-fighting cells in the blood and are distinct from the red (oxygen-carrying) blood cells known as erythrocytes.

WPAI:OA - Work Productivity and Activity Impairment Questionnaire is a well validated instrument to measure impairments in work and activities.