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A localized collection of pus surrounded by inflamed tissue.


A disorder of the skin caused by inflammation of the skin glands and hair follicles; specifically, a form found mainly in adolescents and marked by pimples especially on the face.

Active-controlled trial

A research study that compares the test drug or treatment to standard-of-care therapy (vs placebo).

Adverse reaction

An unwanted effect resulting from taking a drug treatment. Effects may occur suddenly or develop over time (ex: headache, nausea, rash, etc.).

Advocacy and support groups

Organizations and groups that actively support patients and their families by providing valuable resources, including self-empowerment and coping tools.


AIDS (acquired immunodeficiency syndrome) is the most advanced stage of infection with human immunodeficiency virus (HIV). HIV/AIDS can be spread through unprotected sex with an infected person or by sharing drug needles or through contact with the blood of an infected person.


A substance, such as pollen, that causes an allergy.


Medications which may be used for the treatment of dyskinesias (involuntary movement) and wearing off.

Anaplastic lymphoma kinase (ALK) gene

This gene sends signals that make cells grow and divide.


A surgical connection made between two structures (usually tubular ones) such as blood vessels or loops of the bowel. Ends of these two structures are usually stitched or stapled together (anastomosed) by a surgeon after a part of the bowel has been removed.


Low red blood cell count (low hemoglobin). The dilute blood is less able to carry oxygen. Symptoms may include tiredness, pale appearance, palpitations (irregular heart beat) and shortness of breath. Iron deficiency anemia is common. In adults, it is often due to blood loss and sometimes to poor absorption or intake of iron. Blood loss in adults most commonly occurs from the gastrointestinal tract.

Ankylosing spondylitis

A type of arthritis of the spine; it causes inflammation between the vertebrae (bones that make up your spine) and in the joints between your spine and pelvis. In some people, ankylosing spondylitis can affect other joints.

Anti-citrullinated protein (CCP) antibody

Autoantibodies (antibodies directed against one or more of an individual’s own proteins) that are frequently detected in the blood of rheumatoid arthritis patients.


Chemical substances that stop the growth of or kill bacteria, parasites and fungus. Antibiotics do not treat viral infections – antiviral drugs may treat some viruses.


Medications that block neurotransmitter systems.


Any substance that can stimulate the immune system to produce antibodies that combine specifically with them.

Apocrine gland

Apocrine glands are special sweat glands found in hairy areas of the body such as the armpits and groin.


A surgical operation to remove the appendix.


Swelling (inflammation) of the appendix.


A tube-shaped sac located at the junction of the small and large bowel in the lower right abdomen. The function of the appendix is unknown.


A treatment group in a randomized trial. Most randomized trials have two "arms", but some have three "arms" or more.



The practice of using essential oils (generally plant-based) to improve health or a person’s mood.

Art therapy

Helps people manage physical and emotional problems by expressing themselves through art.


A condition that causes pain and inflammation within a joint. For more information click here


This is a rare childhood disease that affects the brain as well as other parts of the body.


Ophthalmic atropine may be used before eye examinations to dilate (open) the pupil (the black part of the eye). This medication can also be used to relieve pain caused by swelling and inflammation of the eye.

Autoimmune disease

An illness that occurs when the body tissues are attacked by its own immune system. The immune system is designed to “seek and destroy” disease in the body, including infectious agents. Patients with autoimmune diseases frequently have unusual antibodies circulating in their blood that target their own body tissues.


An immune response against an organism’s own cells and tissues: antibodies or T cells that attack molecules, cells, or tissues of the organism producing them. Any disease that results from such an aberrant immune response is termed an autoimmune disease.


Azathioprine is used with other medications to prevent transplant rejection (when the transplant is attacked by the body’s immune system) in people who received kidney transplants. It can also be used to treat severe rheumatoid arthritis (a condition in which the body’s immune system attacks the joints, causing pain, swelling, and loss of function) when other therapies have not helped.



Too small to be seen with the naked eye, bacteria exist in the thousands, millions, even billions in and on the body. This is normal and many types of bacteria actually help our bodies. The ‘good’ bacteria are beneficial – ‘bad’ bacteria can cause illness.

Basal-like breast cancer

This cancer make too much of a certain type of protein plus they have too many epidermal growth factor receptors which affect cell growth.


The information first gathered about a patient at the beginning of a study. Data collected throughout the trial are often compared to the baseline to see changes over the course of the trial.

Behcet’s syndrome

A disease involving inflammation of the blood vessels; it may affect many parts of the body.


When a point of view prevents objective judgment on issues relating to the patient. In clinical studies, bias is controlled through blinding and randomization.



A yellow or greenish liquid that is made by the liver, that helps the body to digest fats.

Biologic (drug)

A substance that is made from a living organism or its products, and used in the prevention, diagnosis, or treatment of diseases. Biological drugs include antibodies, interleukins, and vaccines.


The removal of samples of tissue, cells or fluids from the living body. Biopsies can be taken using a biopsy instrument that is passed through the skin or through an endoscope into the organ in question, or is collected by open surgery. A trained specialist (pathologist) examines the tissue under a microscope to establish a precise diagnosis such as cancer.

Blood thinners

If you have heart or blood vessel disease, or if you have poor blood flow to your brain, your doctor may recommend a blood thinner. Blood thinners can decrease the risk of heart attack and stroke by reducing the formation of blood clots in your arteries and veins.

Body surface area involvement

Body surface area (BSA) is the total surface area of the human body. The body surface area is used in many measurements in medicine, including as an indicator (BSA involvement) of the extent and severity of psoriasis.


A localized swelling and inflammation of the skin usually resulting from bacterial infection of a hair follicle and adjacent tissue, having a hard central core, and forming pus.

Bone scan

A bone scan is a procedure that checks for abnormal areas or damage in the bones. Prior to the scan, a very small amount of radioactive material is injected into a vein. This collects in the bones and is detected by a scanner (a special camera that takes pictures of the inside of the body).


Another name for the intestines: the small bowel (duodenum, jejunum and ileum), and the large bowel (colon and rectum).


BRCA 1 is a gene on the human chromosome 17 and BRCA 2 is a gene on chromosome 13. These genes normally help to control cell growth. A person who inherits certain mutations (changes) in one or both of these genes has a higher risk of getting breast, ovarian, prostate, and other types of cancer.


An inflammation of the lining of the tubes which carry air to and from your lungs. People who suffer from bronchitis often cough up thickened mucus, which may be discolored. Bronchitis may be acute (improves within a few days) or chronic (recurring or present for longer periods).


C-reactive protein (CRP)

CRP is a protein produced by the liver that is normally present in trace amounts in the blood serum but is elevated during episodes of acute inflammation. See ERYTHROCYTE SEDIMENTATION RATE (ESR)


Medication to block an enzyme responsible for breaking down levodopa before it reaches the brain; carbidopa is always given in combination with levodopa.


A cancer that starts in the skin or in tissues that line or cover internal organs.


A strong but flexible, somewhat elastic tissue found in some parts of the body (such as the nose, the outer ear, and some joints).

Cat-scratch disease

CSD is an infection caused by the bacterium Bartonella henselae. About half of all cats carry this bacteria. Although the infection does not make cats sick, the scratch or bite of an infected cat can cause symptoms in people.


A cataract is a clouding of the lens in your eye which may affect vision. Cataracts commonly occur in older people.

Catechol O-methyltransferase (COMT) inhibitors

Medications that block an important enzyme responsible for breaking down levodopa before it reaches the brain.


A nonsteroidal anti-inflammatory drug (NSAID) used to relieve pain, tenderness, swelling and stiffness associated with osteoarthritis (arthritis due to a breakdown of the lining of the joints), rheumatoid arthritis, and ankylosing spondylitis.


Cells are the basic building blocks of the body's tissues. The human body is made up of many different types of cells. Human cells vary in size, but all can only be seen with a microscope.

Central nervous system prophylaxis

Chemotherapy or radiation therapy used on the central nervous system (CNS) to prevent cancer spreading there.

Cerebrospinal fluid

The fluid that flows in and around the hollow spaces of the brain and spinal cord, and between the thin layers of tissue that cover and protect the brain and spinal cord.

CHEK2 gene mutation

People with this condition have a mutation in the CHEK2 tumour suppressor gene.


The choroid is the layer of blood vessels and connective tissue that rests between the white of the eye and retina (at the back of the eye). The choroid is part of the uvea and supplies nutrients to the inner parts of the eye.


An inflammation of the choroid.


Persisting over a long period of time. Relating to disease, one that is slow in progressing and long lasting.

Ciliary body

The ciliary body is a structure in the eye that releases a transparent liquid (aqueous humor) inside the eye.


Cirrhosis is a medical condition in which hard scar tissue largely replaces soft, healthy tissue in the liver. Severe scarring of the liver can prevent it from functioning well. It is important to know that cirrhosis is the end result of many kinds of injury to the liver, such as alcohol, hepatitis C, autoimmune liver disease, and others (alone or in combination). Therefore, any chronic liver disease that is severe and progressive can result in cirrhosis.

Clinical effectiveness

The efficacy of the drug or treatment in the “real-life” context of the doctor’s practice. Studying the clinical effectiveness of a drug or treatment serves to confirm the results of the controlled clinical trials used to obtain regulatory approval.



Can be used alone or with aspirin to prevent serious or life-threatening problems with the heart and blood vessels in persons who have experienced a stroke, heart attack, or severe chest pain.

CMV retinitis

Most people are exposed to CMV in their lifetime, but typically only those with weakened immune systems become ill from CMV infection. Symptoms include blind spots, blurred vision and other vision problems as well as floaters.


In epidemiology, a group of individuals sharing common characteristics such as age or gender.



Also known as the large bowel or large intestine. It connects above to the small bowel and food passes through it to form stool. The lower end, known as the rectum, is continuous with the anus.

Colony stimulating factors (CSFs)

These are treatments used to diminish some of the side effects of cancer treatments, particularly bone marrow suppression. CSFs stimulate the bone marrow so that it increases its production of blood cells. With more blood cells the risk of infection, anemia and bleeding is reduced.

Compassionate use

The way experimental therapeutics can be provided prior to final regulatory authorities' approval for use in humans.

This procedure is used to provide treatment to very sick patients who have no other treatment options. Approval from regulatory authorities for the compassionate use of a drug might be obtained on a case-by-case basis.

Consent form

The written document that is signed when giving informed consent. Informed consent is collected according to guidelines from the fields of medical ethics and research ethics. Informed consent can be said to have been given based upon a clear appreciation and understanding of the facts, implications, and future consequences of an action. In order to give informed consent, the individual concerned must have adequate reasoning faculties and be in possession of all relevant facts at the time consent is given.


Constipation means that a person has three or less bowel movements in a week. In most cases, constipation lasts a short time and is not serious.


Can spread from one person or organism to another by direct or indirect contact.


Corticosteroids are a group of natural and synthetic analogs of the hormones secreted by the pituitary gland. They are prescribed on a short-term basis as fast-working medication for particularly severe and painful symptoms.



Corticosteroids are a group of natural and synthetic analogs of the hormones secreted by the pituitary gland. They are prescribed on a short-term basis as fast-working medication for particularly severe and painful symptoms.


Cowden syndrome

Also known as Cowden disease, involves a mutation in the tumour suppressor gene phosphatase and tensin homolog (PTEN).

Crohn’s disease

A type of inflammatory bowel disease that causes irritation of the digestive, or gastrointestinal (GI) tract.


Also known as intermediate uveitis, it affects the ciliary body.


A medication used to treat cancer of the ovaries, breast, blood and lymph system, and nerves (mainly in children). Cyclophosphamide is also used for retinoblastoma (a type of eye cancer that occurs mainly in children), multiple myeloma (cancer in the bone marrow), and mycosis fungoides (tumours on the skin). Cyclophosphamide belongs to a group of cancer medicines called alkylating agents.


Paralysis of the ciliary muscles of the eye.


Ophthalmic cyclosporine is a drug used to increase tear production in people with dry eyes. Cyclosporine works by decreasing swelling in the eye to allow for tear production.


A noncancerous, closed pocket of tissue that can be filled with fluid, pus, or other substance. Cysts feel like large peas under the surface of the skin.



Inflammation of an entire digit (a finger or toe), which can sometimes be painful. Dactylitis can occur in psoriatic arthritis and ankylosing spondylitis.

Deep brain stimulation (DBS)

A type of surgical therapy for Parkinson's disease and essential tremor. DBS involves placing a metal wire into a specific site in the brain and stimulating the site with electrical impulses.


A medical condition that causes a persistent feeling of sadness, loss of interest, and hopelessness.


A dermatologist is a medical doctor specializing in the skin, the diseases of the skin, and the relationship of skin lesions to overall disease.


If a person has diabetes, their body is not able to properly use the sugar that is released from the food they eat. These sugars build up in the body and can make them feel nauseous, very hungry, very thirsty or very sick, with frequent urination.

Diagnostic mammography

Diagnostic mammography is used to x-ray the breast in women who have signs or symptoms of disease, such as pain, a lump or nipple discharge. Doctors may use diagnostic mammography to look for tumours or other abnormalities.


A nonsteroidal anti-inflammatory drug (NSAID) that works by reducing substances in the body that cause pain and inflammation. Diclofenac can be used to treat mild to moderate pain, or signs and symptoms of osteoarthritis or rheumatoid arthritis.

Disease-modifying anti-rheumatic drug (DMARD)

A category of otherwise unrelated drugs defined to slow down disease progression. The term is often used in contrast to non-steroidal anti-inflammatory drugs (which refers to agents that treat the inflammation but not the underlying cause) and steroids (which blunt the immune response but are insufficient to slow down the progression of the disease).


A neurotransmitter that regulates movement and emotions.

Dopamine agonists

Medications that work in a similar way to dopamine.

Double-blind trial

A clinical trial design in which neither the trial patients nor the study staff know which patients 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 expectations of the doctor and the patient in regards to the drug do not affect the outcome.



Any tube, canal, pipe or conduit by which a fluid, air or other substance is conducted or conveyed.


Ductography is an x-ray of the breast ducts (tubes that carry milk from the lobules to the nipple).


Duodopa is the commercial name for a levodopa/carbidopa combination that comes in gel form. It is delivered inside the upper intestine via a small tube inserted directly into the first part of the small bowel, or duodenum. This unique delivery system – called intraduodenal infusion – uses a programmable pump to let the physician and patient individually tune the delivery of active ingredients, suspended as a stable gel, from a cassette worn outside the body.


Efficacy study

Testing the ability of a drug treatment to produce the desired result. A drug passes efficacy trials if it is effective at the dose tested and against the illness for which it is prescribed.

Eligibility criteria

The inclusion and exclusion parameters that define the requirements for patient selection and whether a patient can or cannot participate in the research study.



A disease that slowly damages the air sacs (alveoli) in your lungs. Over time, people with emphysema are increasingly short of breath.


A procedure used to examine the digestive tract; using a flexible tube with a light and camera to view pictures of the digestive tract on a monitor.

Endpoint (outcome)

An outcome or result that the study has been designed to evaluate. Examples of endpoints include: the occurrence of a disease, symptom, sign or laboratory abnormality that constitutes one of the target outcomes of the trial.


Enthesis (plural: entheses) is the point at which a tendon or ligament or muscle inserts into bone, where the collagen fibers are mineralized and integrated into bone tissue.

Enthesitis is inflammation of the entheses, the sites where tendons or ligaments insert into the bone, points where recurring stress or inflammatory autoimmune disease can cause inflammation or occasionally fibrosis and calcification. One of the primary entheses involved in inflammatory autoimmune disease is at the heel, particularly the Achilles tendon.


A chemical substance in animals and plants that aids natural biological processes (such as digestion).

Epidemiological study

Epidemiology is the science of the study of the patterns, causes, and effects of health and disease conditions in defined populations. Epidemiologists help with study design, collection and statistical analysis of data, and interpretation and dissemination of results.

Erythrocyte sedimentation rate (ESR)

The Erythrocyte Sedimentation Rate (ESR) is a blood test that measures the speed at which red blood cells precipitate (settle at the bottom of the test tube) in one hour. When there is inflammation in the body, it produces proteins in the blood, which make the red cells clump together, causing them to fall faster than healthy blood cells. The ESR is a common blood test that is an indirect measure of inflammation, which can be caused by several conditions. CRP is a protein produced by the liver that is normally present in trace amounts in the blood serum but is elevated during episodes of acute inflammation.


A soft muscular tube of the digestive tract that carries food from the mouth to the stomach for digestion.


Estrogen is a hormone made by the body that helps develop and maintain female sex characteristics and plays a role in the growth of long bones. Estrogen can also be made in the laboratory. Estrogen may be used for birth control and to treat symptoms of menopause, menstrual disorders, osteoporosis, and other conditions.

Estrogen receptor

An estrogen receptor is a protein found inside the cells of the female reproductive tissue, some other types of tissue, as well as some cancer cells. The hormone estrogen will bind (attach to) the receptors inside the cells and may cause the cells to grow.

Ethics committee (EC)

A group of individuals formed to protect the interests of patients and address moral issues. Made up of physicians, researchers and community members, the EC reviews, approves and continuously monitors every trial to ensure that research risks are minimized in relation to the potential benefits. Most ethics committees work in an advisory capacity; they can help patients and families reach informed decisions and work with health care providers in order to make complex and difficult decisions.

Every Other Week (EOW)

Treatment that occurs Every Other Week – meaning the treatment alternates every week.

Extra-articular manifestations

Perceptible, visible expressions of a disease or abnormal condition that occur or are situated outside a joint.



Extreme tiredness, “bone weary” exhaustion that doesn’t get better with rest.

First Nations healing

Traditional First Nations healing practices such as special ceremonies, rituals and herbal medicines.


A tunnel that leads from one loop of bowel to another, or that connects the bowel to the bladder, vagina or skin. Fistulas occur most commonly around the anal area.


An episode when the symptoms of a disease or condition break out or intensify rapidly, become suddenly worse or more painful.


Floaters are small spots you may occasionally see in your field of vision. Floaters may appear as dots, threads, or cobwebs.

Food and Drug Administration (FDA)

The United States Department of Health and Human Services’ agency responsible for ensuring the safety and effectiveness of all drugs, biologics, vaccines and medical devices on the market and being tested in the United States.



Gallstones are hard, pebble-like deposits that form inside the gallbladder. Gallstones may be as small as a grain of sand or as large as a golf ball.


A gastroenterologist is a doctor who specializes in the study of digestive organs including the liver.


A surgical procedure for inserting a tube through the abdomen wall and into the stomach. The tube is used for feeding, drainage or medication intake.


Carries the information inside each cell of the body that determines your biological traits, which are features or characteristics that are passed on to you by your parents.


Relating to, caused by, or controlled by genes.


The genetic makeup of an organism or group of organisms with reference to a single trait, set of traits, or an entire complex of traits; the sum total of genes transmitted from parent to offspring.


Glaucoma is a group of diseases associated with damage to the eye's optic nerve. Glaucoma occurs when the fluid pressure inside the eyes slowly rises, damaging the optic nerve. Without treatment, people with glaucoma may slowly lose their peripheral (side) vision. Over time, blindness may result.


A sugar occurring in many fruits, animal tissues and fluids, etc., and having a sweetness about 1/2 that of ordinary sugar.

Good Clinical Practice (GCP)

The GCP defines international quality standards that governments can incorporate into regulations for clinical trials involving human subjects. Good Clinical Practice guidelines include standards on how clinical trials should be conducted. These also define the roles and responsibilities of clinical trial sponsors, investigators, and monitors. Monitors are hired by the sponsor to verify that the data/information at the site (hospital, clinic) is accurate.


A type of immune cell that contains granules (small particles) with enzymes that are released during infections, allergic reactions, and asthma.

Growth factor

A substance made by the body that regulates cell division and cell survival.


Hair follicle

A sac from which a hair grows and into which an oil gland opens.

Health Canada

The Canadian government agency responsible for national public health. Health Canada oversees and regulates phases I through III of all clinical trials conducted in Canada, and it is their duty to make sure sponsors protect their participants’ safety.


In hemodialysis a machine filters wastes, salts and fluid from your blood when your kidneys are no longer healthy enough to do this work well enough on their own.

Hepatitis A

Hepatitis A is a liver disease caused by the hepatitis A virus (HAV). HAV causes the liver to swell and prevents it from working well. HAV is passed from person to person through fecal matter. Most often it is transmitted because of poor hand washing after using the bathroom or changing a diaper, or before preparing and eating food. Unlike hepatitis B and hepatitis C, it does not become chronic (long-term).

Hepatitis B

Hepatitis B is a liver disease caused by the hepatitis B virus (HBV). HBV causes the liver to swell and prevents it from working well. HBV is passed from person to person through bodily fluids such as blood, semen, or vaginal secretions. Most often it is transmitted through sexual contact or from an infected mother to her infant during birth.


A hepatologist is a doctor who specializes in the study of the liver.


In normal cells, the HER2 protein (made with instructions from the HER2 gene) helps to control cell growth. When the HER2 protein is made in larger than normal amounts by cancer cells, the cells may grow more quickly and can spread to other parts of the body.


A virus that affects the skin or the nervous system, often causing blisters.


A condition that occurs when too much hair grows on a woman’s face or body.


A disease caused by a fungus called Histoplasma. This fungus grows in soil and material contaminated with bat or bird droppings. Breathing the fungal spores can cause infection; it is not contagious between people.


HIV (short for human immunodeficiency virus) weakens your immune system by destroying important cells that fight disease and infection. A ‘deficient’ immune system can’t protect you from illness as it normally would. It is sometimes referred to as ‘the AIDS virus’.


A drug used to dilate (enlarge) the pupil of the eye. This drug is used before eye examinations, before and after eye surgery. It can also be used to treat eye conditions, such as uveitis

Hormone receptor tests

These tests measure the amount of certain proteins, called hormone receptors, in cancer tissue. Hormones can attach to these receptors. Having a lot of hormone receptors means that hormones can help the cancer grow.

Hormone replacement therapy

Hormones (estrogen, progesterone, or both) are used to treat women after menopause to replace the hormones no longer produced by the ovaries.



A surgical operation for ulcerative colitis (UC) after removal of the bowel. An internal pouch is made from the ileum and attached to the anus. This means stools are passed through the anus in the usual way. Sometimes referred to as restorative proctocolectomy.

Immune system

The network of cells, tissues, and organs that work together to protect the body and defend it against infectious organisms (bacteria, viruses, etc.) and other harmful substances. Through a series of steps called the immune response, the immune system attacks these organisms and substances.


Suppression of the immune system and its ability to fight infection. Immunosuppression may be due to drugs or diseases.

Inclusion/exclusion criteria

The medical or social standards that determine whether a person can or cannot enter a clinical trial. These criteria are based on factors such as age, gender, the type and stage of a disease, previous treatment history, and other medical conditions. Inclusion and exclusion criteria are not used to reject people personally but rather to identify appropriate patients and keep them safe.


Used to relieve moderate to severe pain, tenderness, swelling, and stiffness caused by osteoarthritis (arthritis due to a breakdown of the lining of the joints), rheumatoid arthritis and ankylosing spondylitis.

Induction phase

The initial treatment given for a disease. Generally, it is part of a standard set of treatments, such as surgery followed by chemotherapy and radiation.


Infections are caused by germs inside the body. Different types of infections include colds, sore throats, rashes, and cuts or wounds that become infected. How they are treated depends on what type of germ caused the infection.


Can be transmitted through the environment, and can spread infection.


Inflammation is a natural process that the body normally uses to protect itself from harm, such as an injury or infection. Affected areas may become red, swollen and painful, and feel hot or warm to the touch.

Inflammatory breast cancer

This type of breast cancer begins in the breast ducts. The cancer cells spread from the ducts to the lymph vessels in the skin of the breast.

Inflammatory disease

A disease characterized by inflammation, where the body’s immune system thinks its own cells are threats, attacking them as they would typically target external threats like foreign bacteria or a virus.

Informed consent

The process of learning the key facts about a clinical trial before deciding whether or not to participate. In order to help patients make that decision, the doctors and nurses involved in the trial explain the study in detail. The study team must also provide any new information to the patient as it becomes available. Informed consent is therefore an ongoing process.


A method of administering fluids, including drugs, into the bloodstream. Also referred to as intravenous infusion.


A hormone, produced by the beta cells of the islets of Langerhans of the pancreas, that regulates the metabolism of glucose and other nutrients.

Interim analysis

The early analysis of data accumulated before all the patients have completed the study. This can serve to detect trends that might justify modification of the protocol, or a change in the type or format of data being collected. These analyses can also be used in scientific publications to reveal early trial results to the scientific community (other researchers and doctors).

Intervention model

The general design describing how interventions will be assigned to participants in a clinical study. Types of intervention models include single group design, parallel design and crossover design. An intervention can include participants receiving drugs, medical devices, procedures, vaccines, other investigational or available products, or non-invasive approaches like surveys, education or interviews.


The long, tube-like organ in the abdomen that links the stomach to the rectum and absorbs food nutrients. It consists of the small and large intestines (also known as the small and large bowel).

Investigator Brochure

The document that includes all current knowledge about the medication being tested, including the medication’s safety data. The Investigator Brochure is part of the package of documents that must be reviewed and approved by the Ethics Committee before a new clinical trial begins.

Ionizing radiation

Ionizing radiation is made (or “given off”) by x-ray procedures, radioactive substances, rays that enter the Earth's atmosphere from outer space, as well as other sources. At high doses, ionizing radiation increases the chemical activity inside cells and can lead to health problems, such as cancer.


The colored portion of the eye containing a circular opening, the pupil, in its center.


A condition involving inflammation of the eye's iris. The iris is a part of the middle layer of the eye (uvea), so iritis is sometimes called anterior uveitis.



Jaundice is the yellowing of the skin and the whites of the eyes. It is caused by accumulation of bilirubin in the body when the liver is not working well.


The point of contact between elements of a skeleton whether movable or rigidly fixed together with the surrounding and supporting parts (as membranes, tendons, or ligaments).


Kawasaki disease

A rare childhood disease that makes the walls of the blood vessels in the body become inflamed; this disease can affect any type of blood vessel, including the arteries, veins, and capillaries.


Kinesiologists are medical specialists who are leaders in the prevention and management of injury and chronic disease through movement. Using exercise, they are devoted to improving performance, health, and overall quality of life.



The enzyme that breaks down milk sugar (lactose).


A type of sugar found in milk and dairy products.


An abnormal change in structure of an organ or body part due to injury or disease.


Involves removal of blood to collect specific blood cells.


The medication most commonly used to treat Parkinson's symptoms.

Li-Fraumeni syndrome

This is a hereditary cancer predisposition syndrome reported in 1969 by Drs. Frederick Li and Joseph Fraumeni from the National Cancer Institute.


The tough bands of tissue that serve to connect the articular extremities of bones or to support or keep an organ in place. Ligaments are usually composed of coarse bundles of dense white fibrous tissue parallel or closely interlaced - they are pliant and flexible, but not extensible.

Liver cancer

The growth and spread of unhealthy cells in the liver. Also known as hepatocellular carcinoma.

Liver failure

Liver failure is the inability of the liver to function.

Liver transplant

A liver transplant is the process of replacing a diseased liver with a donated, healthy liver.


A chronic, autoimmune disease that can damage any part of the body (skin, joints, and/or organs inside the body).

Lupus-like reaction

A reaction that looks like Lupus, defined as an inflammatory connective tissue disease often held to be an autoimmune disease. Occurring chiefly in women, Lupus is characterized by fever, skin rash and arthritis, often by acute hemolytic anemia, and by small hemorrhages in the skin and mucous membranes.

Lyme disease

A bacterial infection that can occur from the bite of an infected tick. The first symptom is generally a rash, which may look like a bull's eye.

Lymph node

A lymph node is a rounded mass of lymphatic tissue surrounded by a capsule of connective tissue. Located in the lymphatic system, these nodes filter lymph (lymphatic fluid), and they store white blood cells. Lymph is a clear fluid that carries cells that help fight infections and other diseases. The lymphatic system is made up of the tissues and organs that produce, store, and carry white blood cells that fight infections and other diseases. Lymphatic vessels extend to all tissues of the body.

Lymph nodes

Small bean-shaped structures that are part of the body’s immune system. Lymph nodes filter substances that travel through the lymphatic fluid, and they contain lymphocytes (white blood cells) that help the body fight infection and disease.


A type of immune cell made in the bone marrow and is found in the blood and in lymph tissue. A lymphocyte is a type of white blood cell.


A cancer of a part of the immune system known as the lymph system.


Magnetic resonance imaging

An MRI is a procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of the body’s interior. These pictures can distinguish between normal and diseased tissue.

Magnetic resonance imaging (MRI)

An MRI is a noninvasive diagnostic technique that produces computerized images of internal body tissues and is based on nuclear magnetic resonance of atoms within the body induced by the application of radio waves.

Maintenance phase

Treatment that is given to help keep cancer from coming back after it has been controlled with treatment. It may include medicines, vaccines, or antibodies that kill cancer cells, and it can be given for a long time.


Synonymous with cancerous. Malignant tumours can invade and destroy tissues around the tumour and spread to other parts of the body.

Masking (blinding)



When cancer cells spread (metastasize) from one part of the body to another where they can grow into new tumours.


A drug used to treat severe psoriasis that cannot be controlled by other treatments. Methotrexate may also be used to treat severe active rheumatoid arthritis and to treat certain types of cancer (including breast cancer, lung cancer, certain cancers of the head and neck, certain types of lymphoma, and leukemia).

Monoamine-Oxidase-B (MAO-B) inhibitor

Medications that enhance the effect of dopamine by preventing its breakdown in the brain.


An immune system cell made in the bone marrow that travels through the blood to tissues in the body where it becomes a macrophage. Macrophages surround and kill microorganisms, consume foreign material, remove dead cells, and boost immune responses.


A slimy, white, jelly-like fluid produced by the lining of the bowel. People with ulcerative colitis (UC) often have a lot of mucus in their stools.


A permanent alteration or change in a gene.


A drug used with other medications to help prevent transplant organ rejection (attack of the transplanted organ by the immune system) in people who have received kidney, heart, and liver transplants.



A drug used to relieve pain, tenderness, swelling, and stiffness caused by osteoarthritis, rheumatoid arthritis, juvenile arthritis, and ankylosing spondylitis.

Naturopathic medicine

An approach based on the belief that the body can be stimulated to heal itself.


A drug used to treat eye pain, redness, and swelling in patients recovering from cataract surgery. Nepafenac is a nonsteroidal anti-inflammatory drugs (NSAID).


Chemical (such as dopamine, acetylcholine, or norepinephrine) which transmits or relays information or signals from one nerve cell (neuron) to other nerve cells or muscle cells.


A lymph node is a rounded mass of lymphatic tissue surrounded by a capsule of connective tissue. Located in the lymphatic system, these nodes filter lymph (lymphatic fluid), and they store white blood cells. Lymph is a clear fluid that carries cells that help fight infections and other diseases. The lymphatic system is made up of the tissues and organs that produce, store, and carry white blood cells that fight infections and other diseases. Lymphatic vessels extend to all tissues of the body.


A small mass of rounded or irregular shape.

Non-steroidal anti-inflammatory drugs (NSAID)

A class of medications that can be used to treat inflammation, reduce joint swelling and relieve pain, tenderness, and stiffness. NSAIDs do not control the disease, only its symptoms. Therefore, they are only taken on an as-needed basis. There are many NSAIDs available, including non-prescription.



SEE Observational study and Observational model

Observational model

The general design and strategy as to identifying and following up with participants during observational studies. Types of observational study models include cohort, case-control, case-only, case-crossover, ecologic or community studies and family-based.

Observational study

A study whereby patients identified as belonging to study groups are assessed for biomedical or health outcomes. Patients may receive diagnostic, therapeutic, or other types of treatments, but the investigator does not assign participants to specific interventions (as in an interventional study).

Occupational therapist (provides occupational therapy)

Health professional trained to help people who are ill or disabled learn in the management of their daily activities.


A doctor who specialises in treating patients with cancer.

Open-label trial

A clinical trial in which both the researchers and the patients know who receives the drug and who receives a placebo.


A medical doctor specializing in the branch of medical science dealing with the anatomy, functions, and diseases of the eye.


Any infection caused by a microorganism that does not normally cause disease in humans; occurs in persons with abnormally weak immune systems (such as AIDS patients or transplant patients receiving immunosuppressive drugs).


A licensed professional who examines the eyes (using suitable instruments or appliances) for defects in vision and eye disorders in order to prescribe corrective lenses or other appropriate treatment.


The bones of a person with osteoporosis are weak and more likely to break. Anyone can develop osteoporosis; however, it is common in older women.


In biology, “overexpression” means to make too many copies of a protein or other substance. Overexpression of certain proteins or other substances can play a role in cancer development.


Paget’s disease

This is a rare form of breast cancer that begins in the breast ducts and spreads to the skin of the nipple and areola. The affected skin may appear to be crusted, scaly, red, or oozing.


A condition that occurs when all layers of the uvea are inflamed.

Parallel assignment

A clinical trial in which two or more groups of participants receive different interventions, e.g., a two-arm parallel design involves two groups of participants, one receiving drug A and the other receiving drug B, therefore “in parallel” to each other.

PEG-J Percutaneous endoscopic gastrostomy

Percutaneous endoscopic gastrostomy (PEG) is a procedure in which a tube (PEG tube) is passed into a patient's stomach in order to provide food or medication. The PEG procedure is an alternative to the open surgical gastrostomy insertion, and does not require a general anesthetic; mild sedation is typically used. PEG tubes may also be extended into the small intestine by passing a jejunal (the second part of the small intestine) extension tube (PEG-J tube).

Peutz-Jeghers syndrome

People with this condition have a mutation in the STK11 (also called LKB1) tumour suppressor gene.


The processes (in a living organism) of absorption, distribution (in the body), metabolism (process by which the body breaks down and converts medication into active chemical substances to treat a disease), and excretion of a drug or vaccine (usually via feces, urine and even respiration).

Philadelphia chromosome

An abnormality of chromosome 22. Bone marrow cells that contain the Philadelphia chromosome are often found in ALL.

Physician global assessment (PGA)

A tool that is used to grade psoriasis plaques on the skin: a score of 0 or 1 indicates that the skin is either clear of psoriasis plaques or they are reduced to a minimum.

Physiotherapist (provides physiotherapy)

Professional who treats people with physical disorders through manipulation, mobilization techniques and prescribing strengthening exercises and advice.


An inactive pill, liquid, or powder that has no treatment value. In clinical trials, experimental treatments are often compared with placebos to assess the treatment's effectiveness.


Placebo effect

A physical or emotional change after a substance is taken, that is not the result of any property or ingredient of the substance. The change may be beneficial, reflecting the expectations of the patient and often, the expectations of the person giving the substance.

Placebo-controlled study

The study method whereby an inactive substance (the placebo) is given to one group of patients while another group receives the drug being tested. The results are then compared to see if the test treatment is more effective than the placebo in treating the condition.


Platelets are found in the blood and spleen. They help form blood clots to slow or stop bleeding, and to help wounds heal. Also called thrombocyte.

Post-marketing trial (PMOS)

Phase IV studies that collect results after the medication has been introduced into the general population. This data complements the results from the three previous trial phases. Most often, these are observational studies that collect data from “real life” patients taking the medication as prescribed by their doctors.


Inflammation of the ileal pouch (an artificial rectum surgically created out of ileal gastrointestinal tissue in patients who have undergone a colectomy).


Prednisolone is a steroid that prevents the release of substances in the body that cause inflammation. The steroid can be used to treat many different conditions such as allergic disorders, skin conditions, ulcerative colitis, arthritis, lupus, psoriasis, or breathing disorders.

Preliminary analysis


Principal investigator

The trial doctor - a highly qualified physician who carries out the research and interacts with the patients. All trial doctors also have additional training in trials and research.

Product monograph

The factual scientific document describing the drug. Devoid of promotional material, it describes the drug’s properties, claims, indications and conditions of use, as well as any information required for the optimal, safe and effective use of the drug.


Progesterone is a hormone made by the body that plays a role in the menstrual cycle and pregnancy. The hormone progesterone can also be made in the laboratory. It is used for birth control and as a treatment for menstrual disorders, infertility, symptoms of menopause, and other conditions.

Progesterone receptor

A progesterone receptor is a protein found inside the cells of the female reproductive tissue, some other types of tissue, as well as some cancer cells. The hormone progesterone will bind (attaches) to the receptors inside the cells and may cause the cells to grow.


The probable outcome or course of a disease; can also refer to the chance of recovery or recurrence.


The relationship of the observation period to the time of patient enrollment. Prospective: looking forward using periodic observations usually collected following patient enrollment.



The study plan on which the clinical trial is based. All plans are carefully designed to safeguard the patients, as well as answer specific research questions. A protocol describes who may participate in the trial, and the schedule of tests, procedures, medications, and regular follow-ups by research staff to monitor the health, safety and effectiveness of the treatment.


Psoriasis is a disease of the skin that causes itchy or sore patches of thick and red skin with silvery scales.

Psoriasis Area and Severity Index (PASI)

A tool physicians use to define the severity of psoriasis. It combines assessment of erythema, induration (plaque thickness) and desquamation (scaling) of the skin and the percentage of affected areas on a scale between 0 and 4.


Thick, yellowish-white fluid formed at the site of inflammation during infection.



A natural radioactive gas produced by the decay of uranium found in soil, rock or water. Radon gas is invisible, odourless and tasteless. Radon can move freely through the soil allowing it to enter the atmosphere or seep into buildings.


A clinical trial method in which the subjects are randomly distributed into groups which are either given the test drug or which serve as the control group.


In a clinical study protocol the rationale is the reason why a clinical study is needed, and which questions researchers want to answer.

Reactive arthritis

Reactive arthritis is a type of arthritis, or joint inflammation that occurs as a “reaction” to an infection somewhere else in the body.


The period during which a trial endeavours to identify and enrol patients.


Recruitment status

Indicates the current recruitment stage of a trial, whether the trial is planned, ongoing, or completed. Designations can include:

- Not yet recruiting: patients are not yet being enrolled
- Recruiting: patients are currently being enrolled
- Active, not recruiting: patients are being treated or examined, but enrolment is completed
- Completed: patients are no longer being examined or treated in the context of the trial
- Suspended: recruitment of patients has halted prematurely, but will potentially resume
- Terminated: recruitment of patients has halted prematurely, and will not resume
- Withdrawn: trial halted prior to enrolment of first patient.


The last part of the colon.


Recurrence means cancer that has recurred or come back. This usually happens after a period of time during which the cancer could not be detected. The cancer recur in the same place as the original (primary) tumor or to another place in the body.

Red blood cell

A type of blood cell that is made in the bone marrow and is found in the blood. Red blood cells contain hemoglobin, which carries oxygen from the lungs to all parts of the body. Evaluation of the number of red blood cells in the blood is usually part of a complete blood cell (CBC) test.


In medicine, describes a disease or condition that does not respond to treatment.


The return of a disease or the signs and symptoms of a disease after a period of improvement.


A period free of active disease with few or no symptoms.

Remission stage

Reduction in or disappearance of signs and symptoms of cancer. In partial remission, only some of the signs and symptoms of cancer have disappeared. In complete remission, all signs and symptoms of cancer have disappeared, even though cancer may still be in the body.

Research study

Carefully planned studies that observe or treat patients in order to develop or discover new treatments or medications. Researchers want to see how well a drug works, how it can be used safely, and learn how to prevent, screen for, better diagnose and treat health issues.


Respiratory therapist

A specialist who helps patients improve their breathing capacity.

Retinal detachment

A retinal detachment means the retina has been lifted or pulled from its normal position. It can occur at any age, but is more likely in people over age 40.


Any of various synthetic or naturally occurring analogs of vitamin A.

Rheumatoid arthritis

A form of arthritis that causes pain, swelling, stiffness and loss of function in your joints. It can affect any joint but is common in the wrist and fingers.

Rheumatoid factor (RF)

An autoantibody of high molecular weight that reacts against lgG immunoglobulins and is often present in rheumatoid arthritis.


A steroid that prevents the release of substances in the body that cause inflammation. Rimexolone is used to treat eye inflammation caused by infections, injury, surgery, or other conditions.


Sacroiliac joint

The joint or articulation between the sacrum (the bone at the bottom of the spine) and ilium (the large, uppermost pelvic bone) - also called sacroiliac ar sacroiliac articulation.


A disease involving inflammation, usually in the lungs, skin, or lymph nodes. Sarcoidosis starts as tiny, grain-like lumps, called granulomas and can affect any organ in the body.


Scintimammography is a type of breast imaging test used to detect cancer cells in the breasts of some women who have already had abnormal mammograms, or who have dense breast tissue. This is not used for screening or in place of a mammogram.


The first visit to the site of a clinical trial, that evaluates whether the person can participate or not. The patient meets the specialist and study coordinator, reviews the informed consent form, undergoes a physical exam and tests, reviews their medical history, etc. If they qualify, a baseline visit is scheduled.

Sex hormone

A hormone, such as estrogen or testosterone, affecting sexual development or reproduction.

Single-blind trial

The study type in which one party, either the investigator or patient, doesn’t know what medication the patient is taking.


Sinus tract

A narrow, elongated channel in the body that allows the escape of fluid.

Speech language pathologist (Speech therapists)

Specialist who helps people with language and communication disorders.

Spine / vertebrae

The backbone. Vertebrae are any of the bony or cartilaginous segments that make up the spinal column.


An organ in the lymphatic system. Located on the left side of the abdomen near the stomach, the spleen makes lymphocytes, filters the blood, stores blood cells, and destroys old blood cells.


Clinical trials are initiated by a sponsor. This can be a company; a university or health care institution; a private or public group; even an individual.


A means of describing or classifying cancer based on the extent of the cancer in the body.

Standards of care (real life treatment)

The current or usual way of treating a disease, outside of a clinical trial.


To destroy microorganisms which adhere to surfaces, usually by bringing objects to a high temperature with steam, dry heat, or boiling liquid.


When joints feel lacking in suppleness.


Narrowing of a hollow tube in the body. Abnormal narrowing of the bowel due to inflammation and scarring.

Study design

The investigative methods used in a clinical study.

Study endpoint

A criterion that will help judge if the treatment is effective or not. For example, in a study evaluating the ability of an antibiotic to treat an infection, an endpoint could be the disappearance of the fever.

Study type

Describes the nature of a clinical trial. Study types include interventional or observational studies.

Sub-optimal response

A response to treatment that is below the most favorable or current one.

Sugar pill


Sweat gland tube

A tubular gland of the skin that excretes perspiration.


Syphilis is a sexually transmitted disease that can affect the genital area, lips, mouth, or anus of both men and women. Syphilis can be transmitted from sexual contact with someone who has it. It can also pass from mother to baby during pregnancy.


Tai chi

A Chinese martial art and form of stylized, meditative exercise. Tai chi is characterized by methodically slow circular and stretching movements and positions of bodily balance.


Pain or discomfort when an affected area is touched. Can describe a joint that is sensitive to touch or palpation.


A tough cord or band of dense white fibrous connective tissue that unites a muscle with some other part in the body, and transmits the force that the muscle exerts.

Therapeutic response (achieve)

The goal of medical treatment is to achieve a therapeutic response in the patient as a consequence. This can be an effect of any kind, judged to be desirable and beneficial - whether the result was expected, unexpected, or even an unintended consequence of the treatment.

Time perspective

The relationship between the observation period and the time of patient enrollment. Time perspective can be prospective: looking forward using periodic observations usually collected following patient enrollment, or retrospective: looking back using observations usually collected prior to patient selection and enrollment.


A group of cells that work together to carry out a specific function.


Toxoplasmosis is a disease caused by the parasite Toxoplasma gondii. The infection can cause damage to the brain, eyes, and other organs.

Traditional Chinese medicine

Traditional Chinese medicine is based on the belief that disease is caused by problems with the flow of energy in the body. Herbal remedies as well as other procedures such as acupuncture and massage are used to restore the flow of energy in the body.


The act of transfusing donated blood, blood products or other fluid into the circulatory system of a person or animal.

Treatment (related to primary purpose)

When the primary purpose of a clinical trial is treatment, it means that the protocol is designed to evaluate one or more interventions for treating a disease, syndrome or condition.

Triple negative breast cancer

This type of breast cancer test negative for the estrogen and progesterone hormone receptors and HER2

Triple-blind trial



A drug that causes the muscles in the eye to become relaxed. This medication dilates (widens) the pupil.


Pulmonary tuberculosis (TB) is a contagious bacterial infection that involves the lungs. It may spread to other organs.


Can also be called a neoplasm. A tumour is an abnormal mass of tissue that occurs when cells divide more than healthy cells or do not die when they are supposed to. Tumors can be benign (that is, not cancer), or malignant (cancerous).

Tumour lysis syndrome

A condition that can occur following treatment of a fast-growing cancer, especially certain leukemias and lymphomas (cancers of the blood). As the tumour cells die, they break apart and release their contents into the blood.

Type 2 diabetes

Diabetes means your blood sugar (glucose) level is too high. Type 2 diabetes, the more common type, means your body does not make or use the hormone insulin properly. Insulin helps glucose get into your cells to give them energy. Without insulin, too much glucose stays in your blood and over time this can lead to serious problems of the heart, eyes, kidneys, nerves, and gums and teeth.

Tyrosine kinase inhibitor (TKI)

A drug that blocks the action of enzymes called tyrosine kinases. Tyrosine kinases affect many cell functions, including cell signaling, growth, and division. These enzymes may be overactive or found at high levels in some types of cancer cells, and blocking them may help keep cancer cells from growing. TKIs are a type of targeted therapy.



An open sore on a body surface. The sore is an area of tissue erosion (loss of surface tissue), for example, of the lining of the gastrointestinal (GI) tract or skin. Due to the erosion, an ulcer is concave like a crater and depressed below the level of the surrounding tissue.


An open sore on a part of the body.

Ulcerative colitis

Ulcerative colitis (UC) is a disease that causes inflammation and sores (ulcers) in the lining of the rectum and colon. It is considered an inflammatory bowel disease.


This is a procedure that uses high-energy sound waves to look at tissues and organs inside the body. These sound waves make echoes that form images of the tissues and organs on a computer screen (sonogram). Ultrasound can be used to help diagnose diseases, such as cancer. It may also be used during pregnancy to check the fetus (unborn baby) and during medical procedures.


Inflammation of the uvea, the pigmented, vascular structure in the eye consisting of the iris, ciliary body, and choroid.



A substance that is usually injected into a person or animal to protect against a particular disease.


An extremely small living thing that causes a disease and that spreads from one person or animal to another. It can only reproduce itself by taking over a cell in the body of its host.

Vogt Koyanagi Harada’s disease

A disease associated with chronic inflammation of melanocytes (specialized cells that produce a pigment called melanin). Melanin gives skin, hair, and eyes their color.



An anticoagulant (blood thinner) that reduces the formation of blood clots.

West Nile virus

A disease spread by infected mosquitoes. Although many infected people experience no symptoms, the infection may be associated with fever, headache, body aches, skin rash, and swollen lymph glands. These symptoms can last a few days to several weeks, and usually go away on their own. If West Nile virus enters the brain, it can be life-threatening.

White blood cell

A type of blood cell made in the bone marrow and found in the blood and lymph tissue. White blood cells are a part of the body’s immune system. They help fight infection and other diseases.