Calories Availability: the average nutritional energy content of the total daily per capita food supply, for a given country, territory, or geographic area, over a specific period in time, usually a year. Technical Note: Calorie availability is derived from food balance sheets standardized for a range of primary food commodities for human consumption, originated from supply/utilization national accounts and maintained by the Food and Agriculture Organization (FAO) of the United Nations.

Cancer: diseases in which abnormal cells divide and grow unchecked. Cancer can spread from its original site to other parts of the body and can be fatal. See also -- hereditary cancer, sporadic cancer.

Candidate Gene: a gene located in a chromosome region suspected of being involved in a disease. See also -- positional cloning, protein.

Cantou: communal non-medical care in 12-15 room units organized around common living areas, in a home-like atmosphere with family participation encouraged.

Cap: a limit on the amount that a payer or group of payers will pay.

Capillary Array: gel-filled silica capillaries used to separate fragments for DNA sequencing. The small diameter of the capillaries permit the application of higher electric fields, providing high speed, high throughput separations that are significantly faster than traditional slab gels.

Capital: an accumulation of financial resources not required for current consumption. This allows a contribution to be made to productive activity by investment in physical capital (such as buildings) and in human capital (such as education and training).

Capital Expenditure: the expenditure that is required for financing permanent or semi-permanent facilities or equipment, such as buildings etc.

Capital Investment: funding for resources such as buildings or other "one-off" purchases such as computer hardware and software and other office equipment.

Capitation, in contrast to Fee-for-Service: a fixed payment to a provider for each listed or enrolled person served per period of time.

Capping: the addition of 7-methlyguanosine residues to the 5΄ end of eukaryotic mRNA.

Carcinogen: something which causes cancer to occur by causing changes in a cell's DNA. See also -- mutagene.

Carrier: an individual who possesses an unexpressed, recessive trait.

Caruncle (Urethral Caruncle): small, red benign tumor that is visible at the posterior part of the urethral meatus. Occurs chiefly in postmenopausal women and usually causes no symptoms.

Case-Based Payment , see Payment: third-party payers pay physicians/ hospitals according to the cases treated rather than per service or per bed days.

Case Control Study: a study in which participants are divided into exposed and non exposed groups and studied over a specific time. A study in which subjects are selected based on their presence of or absence of a selected disease or disorder.

Case History: research that focuses in-depth on a particular (single) phenomenon, place, or person.

Case-Mix: the composition of patients treated by a hospital or another provider.

Case Series: an uncontrolled study of outcomes for a series of patients receiving a particular intervention.

Cash Limit, see Cap: a limit imposed by the government on the amount of cash which a public body may spend during a given financial year.

Catchment Area: a geographic area defined and served by a health plan or a health care provider.

Catchment Population: estimate of the population served by a hospital or other health service unit or facility.

Cathartics: medications that increase the clearing of intestinal contents. Also known as laxatives.

Catheter: narrow, flexible rubber, latex, or silastic tube that is inserted or passed through the urethra or lower abdomen and into the bladder for the purpose of draining urine or performing diagnostic tests of bladder or urethral function.

cDNA Library: a collection of DNA sequences that code for genes. The sequences are generated in the laboratory from mRNA sequences. See also -- messenger RNA.

Cell: the basic unit of any living organism that carries on the biochemical processes of life. See also -- genome, nucleus.

Cell-mediated Cytotoxicity: killing (lysis) of a target cell by an effector lymphocyte.

Cell-mediated Immunity: immune reaction mediated by T cells, in contrast to humoral immunity, which is antibody mediated. Also referred to as delayed-type hypersensitivity.

Census: an enumeration (inventory) of a population, which usually includes demographic information but may also include information on basic health-related issues.

Centimorgan (cM): a unit of measure of recombination frequency. One centimorgan is equal to a 1% chance that a marker at one genetic locus will be separated from a marker at a second locus due to crossing over in a single generation. In human beings, one centimorgan is equivalent, on average, to one million base pairs. See also -- megabase.

Central Repository: a central database that contains the trial registration data sets provided by each Contributing Register.

Centralization: the concentration of managerial functions at one point within the system.

Centralized Planning: Planning governed centrally by the state covering all the goods and services that will be produced and how factors of production shall be allocated between sectors of a business or an economy.

Centromere: a specialized chromosome region to which spindle fibers attach during cell division.

c-erb-b2 Proto-Oncogene: also referred to as HER-2 or neu, this gene encodes a protein that is structurally similar to the receptor for epidermal growth factor. When it is amplified, the gene is of prognostic significance in breast and ovarian neoplasm.

Cerebral Palsy: chronic static neuromuscular disability characterized by aberrant control of movement or posture, appearing early in life and not the result of recognized progressive disease.

Cervix: lower portion of the uterus that connects with the vagina.

Charges, see Price: a price imposed on goods or services.

Chimera (pl. chimaera): an organism with tissues composed of two or more genetically distinct cell types. An organism that contains cells or tissues with a different genotype. These can be mutated cells of the host organism or cells from a different organism or species.

Chimeraplasty: an experimental targeted repair process in which a desirable sequence of DNA is combined with RNA to form a chimeraplast. These molecules bind selectively to the target DNA. Once bound, the chimeraplast activates a naturally occurring gene-correcting mechanism. Does not use viral or other conventional gene-delivery vectors. See also -- gene therapy, cloning vector.

Chi Square: the primary statistical test used or studying the relationship between variables. This is a test used to compare proportions of categorical variables.

Chloroplast Chromosome: circular DNA found in the photosynthesizing organelle (chloroplast) of plants instead of the cell nucleus where most genetic material is located.

Choice of Care Provider: One of the aspects of the responsiveness of health systems whereby those seeking care have a choice between and within health care units, including opportunities for gaining specialist care and second opinions.

Cholinergic: relating to fibers in the parasympathetic nervous system that release acetylcholine.

Chorioamnionitis (Clinical): a clinical presentation that may include maternal fever, maternal and fetal tachycardia, elevated white blood count, uterine tenderness, and foul-smelling vaginal effluent. The process can obviously evolve from mild sub-clinical to clinical disease.

Chorioamnionitis (Pathologic): inflammation of the fetal membranes is a manifestation of an intrauterine infection and is frequently associated with prolonged membrane rupture and long labors. When mononuclear and polymorphonuclear leukocytes infiltrate the chorion, the resulting microscopic finding is designated chorioamnionitis.

Chromatin: an intranuclear and intrachromosomal complex made up to DNA, and histone and nonhistone proteins.

Chromomere: one of the serially aligned beads or granules of a eukaryotic chromosome, resulting from local coiling of a continuous DNA thread.

Chromosomal Deletion: the loss of part of a chromosome's DNA.

Chromosomal Inversion: chromosome segments that have been turned 180 degrees. The gene sequence for the segment is reversed with respect to the rest of the chromosome.

Chromosome: the self-replicating genetic structure of cells containing the cellular DNA that bears in its nucleotide sequence the linear array of genes. In prokaryotes, chromosomal DNA is circular, and the entire genome is carried on one chromosome. Eukaryotic genomes consist of a number of chromosomes whose DNA is associated with different kinds of proteins.

Chromosome Painting: attachment of certain fluorescent dyes to targeted parts of the chromosome. Used as a diagnostic for particular diseases, e.g. types of leukemia.

Chromosome Region p: a designation for the short arm of a chromosome.

Chromosome Region q: a designation for the long arm of a chromosome.

Class I, Class II, and Class III MHC Molecules: proteins encoded by genes in the major histocompatibility complex.

Cleaning: the physical removal of most microorganisms and contamination, using detergent and water.

Clinical Audit, see Outcome: a cyclical evaluation and measurement by health professionals of the clinical standards they are achieving.

Clinical Guidelines , see Guidelines: systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances.

Clinical Practice Guidelines: set of systematically developed statements or recommendations designed to assist practitioner and patient in making decisions about appropriate health care for specific clinical circumstances. Such guidelines are designed to assist health care practitioners in the prevention, diagnosis, treatment, and management of specific clinical conditions.

Clinical Study: research that focuses on some aspect of a biomedical event, technology, or intervention.

Clinical Trials: these are experiments in which the investigator intervenes rather than observes and is the best test of cause-and-effect relationship. The gold standard of clinical trials is the randomized experiment. Randomization is important because it equalizes baseline characteristics of the subjects so that the comparison of the treatments is fair. If randomization is not feasible, possible non-random standards of comparison must include patients similar to the treated group. Randomization is the current norm of demonstrating efficacy and safety of investigational methods.

Clinical Trial, Interventional: any research study that prospectively assigns human participants or groups of humans to one or more health-related interventions to evaluate the effects on health outcomes. Interventions include but are not restricted to drugs, cells and other biological products, surgical procedures, radiologic procedures, devices, behavioral treatments, process-of-care changes, preventive care, etc.

Clinical Trial Register: the formal record of an internationally agreed minimum amount of information about a clinical trial (trial registration data set). This record is usually stored in and managed using a database.

Clinical Trial Registry: the entity that houses the clinical trial register. It is responsible for ensuring the completeness and accuracy of the information the register contains, and that the registered information is used to inform health care decision making.

Clonal Selection Theory: the prevalent concept that specificity and diversity of an immune response are the result of selection by antigen of specifically reactive clones from a large repertoire of preformed lymphocytes, each with individual specificities.

Clone: an exact copy made of biological material such as a DNA segment (e.g., a gene or other region), a whole cell, or a complete organism. A population of cells derived from a single cell by asexual division.

Clone Bank: see -- genomic library.

Cloning: using specialized DNA technology to produce multiple, exact copies of a single gene or other segment of DNA to obtain enough material for further study. This process, used by researchers in the Human Genome Project, is referred to as cloning DNA. The resulting cloned (copied) collections of DNA molecules are called clone libraries. A second type of cloning exploits the natural process of cell division to make many copies of an entire cell. The genetic makeup of these cloned cells, called a cell line, is identical to the original cell. A third type of cloning produces complete, genetically identical animals such as the famous Scottish sheep, Dolly. See also -- cloning vector.

Cloning Vector: DNA molecule originating from a virus, a plasmid, or the cell of a higher organism into which another DNA fragment of appropriate size can be integrated without loss of the vector's capacity for self-replication; vectors introduce foreign DNA into host cells, where the DNA can be reproduced in large quantities. Examples are plasmids, cosmids, and yeast artificial chromosomes; vectors are often recombinant molecules containing DNA sequences from several sources.

Closed-Ended Questions: fixed-choice questions that require the respondent to choose a response from the choices provided.

Clue Cells: vaginal cells covered with bacteria; commonly present in women who have a vaginal infection.

Cluster Sampling: a cluster sample is one in which the whole population being studied is divided into clusters or groups, and a selection of these clusters is then made, and the entire population or a random sample of subjects within these sub-clusters are sampled. (e.g. if the sampling frame was an entire city, then the city would be broken down into city blocks and certain randomly selected city blocks would be sampled instead of the entire city.

Code: see -- genetic code.

Codominance: situation in which two different alleles for a genetic trait are both expressed. See also -- autosomal dominant, recessive gene.

Co-Dominant: alleles that are different from each other, but both are expressed in the phenotype.

Codon: a section of DNA (three nucleotide pairs in length) that codes for a single amino acid. See -- genetic code.

Cohort Study: an observational study following a group over time, comparing the outcomes of subsets who received different types of care; because random allocation is not used, matching or statistical adjustment at the analysis stage should be used to minimize the influence of factors other than the intervention or factor of interest.

Collaborating Register: can be any clinical trial register that registers trials prospectively (that is, before the first participant is recruited). There are 2 types of Collaborating Register: Contributing and Non-Contributing.

Colony-Forming Units: hematopoietic progenitors that proliferate and give rise to a colony of hematopoietic cells.

Colony-Stimulating Factor: a polypeptide that promotes the growth of hematopoietic progenitors.

Co-Insurance (rate), see Cost-Sharing: cost-sharing in the form of a set proportion of the cost of a service.

Coisogenic or Congenic: nearly identical strains of an organism; they vary at only a single locus.

Command and Control Economy, see Semashko System: either government regulation of a health care market by detailed central planning and fixing of prices, quantities and capacity; or government regulation of a public integrated health care system via line management, with the aim of planning and managing the allocation of resources and the pursuit of efficiency objectives without relying on markets or competition.

Commissioning: the process by which the health needs of the population are defined, priorities determined and appropriate services purchased and evaluated.

Commissioning Services: the process of identifying the need for services and making a contract with those able to provide them.

Committed Cell: a cell committed to the production of specific antibodies to a given antigen determinant. Committed cells include primed cells, memory cells, and antibody-producing cells.

Community Effectiveness, see Effectiveness: the ability of a particular medical action to alter the national history of a particular disease for the better, under actual conditions of practice and use.

Community Participation: involving the community in an activity such as the planning of projects or carrying out a HIA. There are a number of models of community participation, some of which are outlined in the Gothenburg consensus paper on HIA (WHO, 1999).

Community Rating: technique for adjusting insurance premiums according to family size or income.

Community Study: used in this document to describe research conducted in a community setting other than a hospital or other health-care facility; a community study may or may not be population based; subjects may include members from one, several, or all of the groups that comprise a community, including: school children or other adolescents, business or professional people, men (in general), women (in general), women of reproductive age, factory workers, members of the clergy, local health-care workers, local politicians or policy-makers, etc.

Comparative Genomics: the study of human genetics by comparisons with model organisms such as mice, the fruit fly, and the bacterium E. coli.

Comparative Genomic Hybridization: a cytogenetic method based on a combination of fluorescence microscopy and digital image analysis. Differentially labeled test DNA and normal reference DNA are hybridized simultaneously to normal chromosome spreads. Hybridization is detected with two different fluorochromes. Deletion, duplication, or amplifications are seen as changes in the ratio of the intensities of the two fluorochromes along the target chromosomes.

Comparative Study: a study whereby one or more characteristics of two or more groups, places, institutions, etc. are compared.

Competition: Rivalry between two or more sellers for revenue, market share, or other advantage.

Complement (C'): a multifactorial system of one or more normal serum components characterized by their capacity to participate in certain and specific antigen-antibody reactions.

Complement Activation: promotion of the killing or lytic actions of complement.

Complement Cascade: a precise sequence of events usually triggered by an antigen-antibody complex, in which each component of the complement system is activated in turn.

Complement Fixation: the fixation of C' to an antigen-antibody complex.

Complementary DNA (cDNA): DNA that is synthesized in the laboratory from a messenger RNA template.

Complementary DNA (cDNA) Probe: a DNA sequence that is exactly complementary to mRNA, lacking introns and regulatory regions.

Complementary Sequence: nucleic acid base sequence that can form a double-stranded structure with another DNA fragment by following base-pairing rules (A pairs with T and C with G). The complementary sequence to GTAC for example, is CATG.

Complex Trait: trait that has a genetic component that does not follow strict Mendelian inheritance. May involve the interaction of two or more genes or gene-environment interactions. See also -- Mendelian inheritance, additive genetic effects.

Complicated Abortion: spontaneous or induced abortion that results in complications, such as infection or bleeding.

Comprehensive (maxi) HIA: a comprehensive or "maxi" HIA is a much more detailed rigorous exercise than either a rapid or intermediate HIA. It usually involves the participation of the full range of stakeholders, an extensive literature search, secondary analysis of existing data and the collection of new data. "Control" populations may also be used (Parry and Stevens, 2001).

Compulsory Health Insurance: health insurance under an obligatory scheme by law, usually with contributions that are income-related.

Computational Biology: see -- bioinformatics.

Concurrent HIA: concurrent HIA is carried out whilst a policy, program or project is being implemented.

Confidence Interval (CI): the computed interval with a given probability, i.e., 95%, that the true value of a variable such as a mean, proportion or rate is contained within the interval. Confidence interval (e.g. 95%) represents a range of values within which it is 95% certain that the true population value of the rate is present. The range of values that is believed to contain the true value within a specific level of certainty.

Confidentiality: one of the aspects of the responsiveness of health systems whereby privacy in the context of privileged communication (such as patient-doctor consultations) and medical records is safeguarded. In genetics, the expectation that genetic material and the information gained from testing that material will not be available without the donor's consent. An ethical practice for maintaining privacy and protecting the identity of research subjects.

Confounding: a situation in which the effects of two processes are not separated. The distortion of the apparent effect of two processes is not separated. The distortion of the apparent effect of an exposure on risk brought about by the association with other factors that can influence the outcome.

1. A relationship between the effects of two or more casual factors as observed in a set of data such that it is not logically possible to separate the contribution that any single causal factor has made to an effect.
2. A situation in which a measure of the effect of an exposure on risk is distorted because of the association of exposure with other factor(s) that influence the outcome under study.