(kŭrv )
[L. curvus, bent, crooked]
A bend, chart, or graph.
The steepest part of the curved structure of a contact lens, where that part fits the shape of the patient's cornea.
SEE: Normal distribution.
SEE: curve of Carus
In radiographic film analysis, the curve derived by graphing the exposure to the film versus the film density. Analysis yields information about the contrast, speed, latitude, and maximum and minimum densities of the film or film-screen system. Digital radiography systems exhibit linear curves.
SYN: SEE: D log E curve; SEE: Hurter and Driffield curve; SEE: sensitometric curve
SEE: Characteristic curve
A graph charting the effect of a specific dose of drug, chemical, or ionizing radiation.
A graph of the disappearance rate of a known amount of injected dye from the circulation; used to measure cardiac function.
A chart or graph in which the number of new cases of an illness is plotted over time.
SEE: Normal distribution.
A graph of heights and weights, head circumference, and body mass index of infants and children of various ages. A line connecting the data points produces the curve. Usually the changes in height and weight are shown on the same chart. Growth charts are specific for age and gender.
In studies of human physiology (and in other studies), an increase in bad outcomes that occurs when variables are either too low or too high, e.g., an increase in death from heart disease in patients with hypotension or hypertension. People in the middle of J curves, e.g., those whose blood pressures are approx. 140/80, tend to have the least risk of disease or death.
The effect of learning or practice on the performance of an intellectual or physical task. The term describes the acquisition of competence with experience, time, and training.
SEE: Normal distribution.
A plot of performance trials to determine the average of a subject or of a group of subjects across a number of practice trials.
ABBR: ROC curve A plot of the fraction of true positive test results versus the fraction of false positive test results; the sensitivity of a test versus (1 − the test specificity).
SYN: SEE: receiver operating characteristic
SEE: Characteristic curve
SEE: curve of Spee
SEE: Stephan curve
In radiobiology, a dose-response curve.
SEE: dose-response curve
The mathematical relation that plots the physical and chemical behaviors of dental (and other) materials as their temperature decreases over time.