One of many dimensions or ways of measuring or describing an object or evaluating a subject : 1. In a mathematical expression, an arbitrary constant that can possess different values, each value defining other expressions, and can determine the specific form but not the general nature of the expression; e.g., in the equation y = a + bx, a and b are parameters. 2. In statistics, a term used to define a characteristic of a population, in contrast to a sample from that population; e.g., the mean and standard deviation of a total population. 3. In psychoanalysis, any tactic, other than interpretation, used by the analyst to further the patient's progress. [para- + G. metron, measure]
- enzyme parameters those factors and constants that govern the rate of an enzyme-catalyzed reaction, e.g., Vmax and Km.
- infection transmission p. the proportion of total possible contacts between infectious cases and susceptibles that lead to new infections. SEE ALSO: serial interval, mass action principle.
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n.
(in medicine) a measurement of some factor, such as blood pressure, pulse rate, or haemoglobin level, that may have a bearing on the condition being investigated.
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pa·ram·e·ter (pə-ramґə-tər) [para- + -meter] 1. a constant in a mathematical expression that distinguishes specific cases, having a definite, fixed value in one case but different values in other cases. For example, in the equation of a straight line, y = mx + b, m and b are parameters that specify a particular straight line; changing m changes the slope of the line, while changing b changes the point at which the line crosses the y-axis. 2. in statistics, a value that specifies one of the various members of a family of probability distributions, e.g., the mean or variance of a normal distribution. A parameter is often thought of as the “true value†or “population value†as opposed to the observed value or sample value. 3. a variable whose measure is indicative of a quantity or function that cannot itself be precisely determined by direct methods; e.g., blood pressure and pulse rate are parameters of cardiovascular function, and the level of glucose in blood and urine is a parameter of carbohydrate metabolism.Medical dictionary. 2011.