index case

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Related to index case: index patient, primary case


In human genetics, the patient or member of the family that brings a family under study.
Synonym(s): index case
[L. probo, to test, prove]

index case

1. The earliest identified occurrence of a disease or disorder, usually as part of an epidemiological investigation of a patient population or a genetic study of a family.
2. The first patient who has such a disease or disorder. Also called proband, propositus.

index case

Etymology: L, indicare, to make known
(in epidemiology) the first case of a disease, as contrasted with subsequent cases. See also propositus.

index case

See Index patient, see there.

in·dex case

(in'deks kās)
The first case in the investigation of the outbreak of a potentially epidemic disease.

Index case

The first case of a contagious disease in a group or population that serves to call attention to the presence of the disease.
Mentioned in: Syphilis


in epidemiology, an animal which has the specified disease or condition which is under investigation.

case abstract
a structured summary of a case report suitable for computer entry; permits machine sorting and retrieval and leads an investigator to the original paper records on which detailed descriptions must be based.
case-control sampling
selection of cases as a sample to use in a case-control study (below).
case-control study
a retrospective, analytical, epidemiological study. A group of pre-existing cases of the disease are matched with a selected group of control animals that do not have the disease so that the presence or otherwise of an hypothesized disease determinant can be ascertained in both groups.
case fatality rate
the proportion of cases with a specified condition which die within a specified time.
case finding
the strategy of surveying a population to find the sick animals that are the foci of infection; an essential early step in the eradication of any disease.
case history
the collected data concerning an individual, contact and related animals, environment and management procedures, including any past medical history and any other information that may be useful in analyzing and diagnosing the case or for instructional or research purposes.
index case
the first case recorded in an outbreak.
case management
care of a sick animal including specific and supportive medication, surgical intervention, housing, bedding, nutrition, restraint, collection of specimens for submission to laboratory or stall-side tests.
case population
the group of animals in the total population which are sick or infected, as distinct from the control population, which are not sick or infected.
case recording
entry in records of the clinical findings of individual sick animals. May be structured or unstructured, paper or machine, with or without the accounting record for the case.


pl. indexes, indices [L.] the numerical ratio of measurement of any part in comparison with a fixed standard.

index case
the first case of a disease in a group to be brought to the attention of the clinician.
Color index
a publication of the Society of Dyers and Colorists and the American Association of Textile Chemists and Colorists, containing an extensive list of dyes and dye intermediates. Each chemically distinct compound is identified by a specific number, the CI number, avoiding the confusion of trivial names used for dyes in the dye industry. The Royal Horticultural Society, London, produces a similar document to aid in the identification of flower colors.
erythrocyte i's
see erythrocyte indices.
index Medicus
a monthly publication of the National Library of Medicine, in which the world's leading biomedical literature is indexed by author and subject.
opsonic index
a measure of opsonic activity determined by the ratio of the number of microorganisms phagocytized by normal leukocytes in the presence of serum from an animal infected by the microorganism, to the number phagocytized in serum from a normal animal.
phagocytic index
the average number of bacteria ingested per leukocyte of the patient's blood.
production index
a method of expressing production compared with a potential or target.
refractive index
the refractive power of a medium compared with that of air (assumed to be 1).
therapeutic index
originally, the ratio of the maximum tolerated dose to the minimum curative dose; now defined as the ratio of the median lethal dose (LD50) to the median effective dose (ED50). It is used in assessing the safety of a drug.
index Veterinarius
a periodic listing of all publications in the veterinary literature by the Commonwealth Agricultural Bureaux, United Kingdom. Also available on on-line data search.
vital index
the ratio of births to deaths within a given time in a population.
References in periodicals archive ?
In this study, we screened pediatric and adult family members of index cases with brucellosis to detect unrecognized infected family members.
The duration of association of the newly diagnosed patients with the index case could not be ascertained in this study.
The collective temporal relationship of the index case and remaining 8 cases in the outbreak is summa-rized in Fig 1.
d--Other parameters: The nuclear family of the index case (child), the nuclear family of the index case (marital), the nuclear family of father and mother's index case.
In addition to the index case (see above), six standardised case vignettes of patients with different combinations of primary and secondary diagnoses, procedures, age and length of stay were defined (Table 2).
Sepsis can lead to gangrene but as sepsis has been ruled out in the index case and no other etiology found, therefore it has prompted us to make the diagnosis of idiopathic bilateral upper limb gangrene in this newborn.
The 10th case actually was one of the nurses who also had primary contact with the index case.
Officials then can locate other people exposed to the index case.
When the infectiousness of the index case is relatively low, changes in the supply flow rate will not cause any change in the protective effectiveness of the air delivery system, while for the index case of relatively moderate infectiousness, an increase in supply flow rate up to 6 ACH will improve the protective effectivenes.
So far, epidemiologic investigations in Alaska failed to identify any episodes of secondary Hia infections transmitted from an identified index case, Dr.
By comparing STR pattern of X-chromosome allele of index case with X-chromosome alleles of the mother, the diseased or affected X-chromosome was ascertained.