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The Canary Database
Center for One Health Research
University of Washington




Glossary of related terms

Term Definition
Aggregate study (ecologic study) Studies in which comparisons are made between groups but exposures are not measured on the individual level. For instance, assessments are done on the community, population, or group levels.
Animal type A classification describing the nature of the relationship between the animals being studied and the humans to whom the studied animals might be in close proximity. Possible values include companion, livestock, or wildlife.
Author(s) Identifies the author or authors of the study.
Backward directionality Backward directionality describes a methodology in which individuals with a certain condition are compared with individuals without the condition in terms of history of previous exposures, thereby moving backward in time. Case-control studies are often considered backward directional studies.
Case A subject meeting inclusion or exclusion criteria in a study. For instance, those subjects who contract the disease in the study.
Case-control study Study groups are defined on the basis of disease (or outcome) status. The frequency of the risk factor (exposure) in the cases (diseased) is compared with the frequency of the risk factor (exposure) in the controls (nondiseased).
Causative factors Causative factors examined in a given study may be a specific hazard or disease agent, such as inorganic lead or the Lyme disease spirochete Borrellia Burgdorferi. Factors noted by curators could also include host susceptibility factors such as age, species, or gender, as well as environmental factors such as "urbanization" or "climate change". These causative factors relate to the animal population being studied, and do not necessarily correlate with human health risk.
Cohort study A study in which a clearly identified group is characterized by exposure and is followed for the outcome.
Companion animal Animals serving as companions such as dogs, cats and other pets. *
Controls According to the classification algorithm, identifies whether the study used control animals from the same population as the affected animals (Yes or No). For example, many studies compare control animals from an "uncontaminated" reference site to animals from a "contaminated" site. In this case, the control field would indicate "no", controls not drawn from the same population.
Country Identifies the country in which the study was completed.
Cross-sectional study A study of a population at a single point in time.
Curator's Comments Includes any comments on the study or its methodology not addressed in other fields. There is no specific format for this field and it is not intended to include a comprehensive critique of the study.
Descriptive study (case report) Studies with no analytic comparisons made between groups. These reports are descriptive in nature.
Disease outcomes This field includes the disease outcome(s) of interest in the animal population being studied. Some studies include more than one endpoint, such as immune dysfunction as well as kidney disease. This field does NOT necessarily correlate with a similar disease outcome in humans, although it provides data to explore such relationships.
Experimental study Studies in which variables are controlled by the researcher. Because of this control, studies can better provide confirmation of an association between an exposure and an outcome.
Forward directionality A methodology in which individuals with a certain exposure are compared over time with individuals without exposure to determine if rates of disease are different between the two groups. Cohort studies are considered forward directional studies.
Institution Identifies the institution where the study was completed.
Livestock Domestic animals, such as cattle or horses, raised for home use or for profit, especially on a farm.
MeSH term National Library of Medicine's Medical Subject Headings.
Principal exposure The study key word representing the most specific and important environmental hazard studied. If more than one exposure is given equal weight in the analysis, multiple exposures may be entered in the database.
Principal species Identifies the principal species studied. If more than one species is given equal weight in the analysis, multiple species may be entered.
PubMed Identifier Identification number from the PubMed MEDLINE database.
Sample Size The number of subjects under study.
Sampling According to the classification algorithm, records whether animals were sampled according to outcome (health effect) or exposure (environmental hazard). For example, in a case-control study, sampling would be by outcome, while in a cohort study, it would be by exposure. In a cross-sectional study, sampling could be by either outcome or exposure, since these are measured simultaneously.
Source The full citation for the journal or other publication in which the study appeared (e.g., title, volume, number, pages, and date for a journal citation).
Species The species designations of animals under study.
Study type According to the classification algorithm, identifies the methodology used to study the relationship between environmental exposure and health effect. For studies with multiple methodologies, more than one type may be selected. Possible values include aggregate, case-control, cohort, cross-sectional. descriptive, or experimental. For a detailed explanation of each, read our study methodologies overview.
Timing Records whether data were collected from historical records, concurrently with analysis, or repeatedly over time. Valid entries are: Historical, Concurrent, Repeated.
Title The full title of the study.
Unique Identifier Unique identification number assigned by and specific to this database.
Wildlife Wild animals, especially animals living in a natural, undomesticated state. *

* Definition taken from The American Heritage? Dictionary of the English Language, Fourth Edition.


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