| growth rate | <biology, cell culture, ecology> The rate, or speed, at which the number of organisms in a population increases. This can be calculated by dividing the change in the number of organisms from one point in time to another by the amount of time in the interval between the points of time. The phrase is most often used to describe growth of cells or microorganisms in laboratory cultures and usually expressed as the generation time. (21 Jun 2000) |
|---|---|
| growth rate of population | <epidemiology> A measure of population change in the absence of migration, comprising addition of newborns and subtraction of deaths; the result is known as the natural rate of increase of the population; it is the difference between the crude birth rate and the crude death rate. (05 Mar 2000) |
| mitotic rate | The proportion of cells in a tissue that are undergoing mitosis, expressed as a mitotic index or, roughly, as the number of cells in mitosis in each microscopic high-power field in tissue sections. (05 Mar 2000) |
| morbidity rate | The sickness rate, the number of people who are sick or have a disease compared with the number who are well. (09 Oct 1997) |
| mortality rate | <statistics> The proportion of deaths in a population or to a specific number of the population. (18 Nov 1997) |
| mortality rate, foetal | The ratio of foetal deaths to the sum of the births (the live births + the foetal deaths) in that year. In the united states, the foetal mortality rate plummeted from 19.2 per 1,000 births in 1950 to 9.2 per 1,000 births in 1980. (12 Dec 1998) |
| mortality rate, infant | The number of children dying under a year of age divided by the number of live births that year. The infant mortality rate in the united states, which was 12.5 per 1,000 live births in 1980, fell to 9.2 per 1,000 live births in 1990. (12 Dec 1998) |
| mortality rate, maternal | The number of maternal deaths related to childbearing divided by the number of live births (or by the number of live births + foetal deaths) in that year. The maternal mortality rate in the united states in 1993 (and 1994) was 0.1 per 1,000 live births, or 1 mother dying per 10,000 live births. (12 Dec 1998) |
| mortality rate, neonatal | The number of children dying under 28 days of age divided by the number of live births that year. The neonatal mortality rate in the united states, which was 8.4 per 1,000 live births in 1980, declined to 5.8 per 1,000 live births in 1990. (12 Dec 1998) |
| concordance rate | The proportion of a random sample of pairs that are concordant for a trait of interest. A high rate of concordance may be generated in several ways, many of which may result from irrelevant bias; but broadly it is taken as evidence of causal connection (e.g., in the case of identical twins, a genetic component or in spouses of assortative mating). (05 Mar 2000) |
| contact rate | <epidemiology> The rate at which susceptibles meet infecteds. Usually measured as individuals per unit time. (05 Dec 1998) |
| mutation rate | The frequency with which a particular mutation appears in a population or the frequency with which any mutation appears in the whole genome of a population. Normally the context makes the precise use clear. See: fluctuation analysis. (18 Nov 1997) |
| critical rate | A heart rate at which aberration or incomplete block will occur; a result of shortening of cycle length so that it barely includes the refractory period. (05 Mar 2000) |
| crude birth rate | <epidemiology> The number of live births in a year divided by the population size. (05 Dec 1998) |
| crude death rate | <epidemiology> The number of deaths in a year divided by the population size. (05 Dec 1998) |