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C - D of terms

CASE CONTROL STUDY: A scientific study that compares a group of people with a disease (such as leukemia) to a similar group of people without that disease. This type of study compares the levels of exposure (for example, radiation or chemical) each group had before appearance of the disease.

CHEMOEMBOLIZATION: A treatment where chemotherapy agents are supplied to the blood vessel supplying a tumour, usually in a form such as beads that then block the bloody supply so trapping the chemotherapy agent into the tumour site. When this process is performed in the liver it is called Transarterial Chemoembolization (TACE).


CLINICAL: Pertaining to or founded on observation and treatment of human participants or patients, as distinguished from theoretical or basic science.

CLINICAL INVESTIGATOR: A medical researcher in charge of carrying out a clinical trial's protocol.

CLINICAL RESEARCH ASSOCIATE (CRA): Person employed by the study sponsor or clinical research coordinator to monitor a clinical trial at one or more participating sites. The CRA is responsible for ensuring all clinical studies are conducted according to study protocol, within regulations and ICH guidelines.

CLINICAL RESEARCH COORDINATOR (CRC): Site administrator for the clinical trial who is responsible for coordinate administrative activities between field and home offices staff, such as the collection of essential documents, distribution of supplies and site selection. Also called research, study or health care coordinator, data manager, research nurse or protocol nurse.

CLINICAL TRIAL (CT): Clinical trials, also known as clinical studies, test potential treatments in human volunteers or patients to see whether they should be further investigated or approved for wider use in the general population. A treatment could be a drug, medical device, or biologic, such as a vaccine, blood product, or gene therapy. Potential treatments, however, must first be studied in laboratory models or animals to determine its safety before they can be tried in people. Treatments having acceptable safety profiles for the disease or condition and showing the most promise are then moved into clinical trials. Clinical trials are an integral part of new product discovery and development, and are required by all regulatory agencies (e.g., the Food and Drug Administration (FDA) in the United States), before a new product can be brought to the market.

COMMUNITY-BASED CLINICAL TRIAL (CBCT): A clinical trial conducted primarily through primary care physicians rather than researchers at academic facilities.

COMPASSIONATE USE: A method of providing experimental therapeutics prior to final regulatory agency approval for use in humans. This procedure is used with very sick individuals who have no other treatment options. Often, case-by-case approval must be obtained by the patientʼs physician from the regulatory agency for “compassionate use” of an experimental drug or therapy.

COMPLETE RESPONSE (CR): The term used for the absence of all detectable cancer after treatment. Complete response doesn't necessarily mean that someone is cured, although it is the best result that can be reported. Any measurable cancer is gone and there is no evidence of disease.

COMPUTERISED TOMOGRAPHY (CT): A type of scan using computer software to resolve many X-Ray images taken from varying angles to provide a cross-sectional image of the body, or specific parts of the body.

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.

CONJUNCTIVAL MELANOMA: A melanoma found in the lining of the eye, conjunctival melanoma accounts for only 2% of all ocular malignancies, which themselves make up only 3-4% of all melanomas. It is a very rare condition which is often bracketed with other eye cancers although is genetically distinct. Conjunctival Melanoma has more in common with Mucosal Melanoma and often displays NRAS and BRAF mutations which are seen in about half of all conjunctival melanomas.   

CONTRACT RESEARCH ORGANIZATION (CRO): A commercial organization contracted by a research and development organization to perform one or more research-related functions.

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

CONTRAST AGENT: A substance given to a patient before a scan to help contrast lesions and their structure in the imaging process.

CONTROL GROUP: A control is the standard by which experimental observations are evaluated. In many clinical trials, one group of patients will be given an experimental drug or treatment, while the control group is given either a standard treatment for the illness or a placebo.

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.

CRYOBLATION: Cryoablation is a type of ABLATION that uses extreme cold to destroy tumours. A hollow needle, through which cooled, thermally conductive, fluids are circulated, is placed through the skin and into the tumour using imaging guidance .

CYBERKNIFE: This is a method of delivering radiotherapy, with the intention of targeting treatment more accurately than standard radiotherapy. This is an example of STEREOTACTIC RADIOSURGERY.

DATA SAFETY MONITORING BOARD (DSMB): A committee, independent of the sponsor, composed of clinical research experts that reviews 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.

DECLARATION OF HELSINKI: A series of guidelines adopted by the 18th World Medical Assembly in Helsinki, Finland in 1964. The Declaration addresses ethical issues for physicians conducting biomedical research involving humans. Recommendations include the procedures required to ensure subject safety in clinical trials, including informed consent and Ethics Committee reviews.

DELCATH: The company who provide the equipment and expertise for PERCUTANEOUS HEPATIC PERFUSION are Delcath Systems Ltd. Their name has become synonymous with the treatment itself, much like the terms ‘Xerox’ or ‘Hoover’ are used to mean ‘Photocopying’ or ‘Vacuum Cleaning’

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.

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