# Table 3 Textual definitions for classes in Figure2

Class label Textual definition
Epidemiological parameter A parameter describing an epidemiological entity or event.
Demographic parameter A parameter describing a demographic characteristic.
Incidence rate The rate at which new events occur in a population. The numerator is the number of new events that occur in a defined period or other physical span. The denominator is the population at risk of experiencing the event during this period, sometimes expressed as person-time; it may instead be in other units, such as passenger-miles.
Net reproductive rate In infectious disease epidemiology, the average number of secondary cases that will occur in a mixed host population of susceptibles and nonsusceptibles when one infected individual is introduced. Its relationship to the basic reproductive rate (R0) is given by R = R0x, where x is the proportion of the host population that is susceptible.
Basic reproductive rate A measure of the number of infections produced, on average, by an infected individual in the early stages of an epidemic, when virtually all contacts are susceptible.
Attack rate The proportion of a group that experiences the outcome under study over a given period (e.g., the period of an epidemic). This “rate” Â can be determined empirically by identifying clinical cases and/or by means of seroepidemiology. It also applies in noninfectious settings (e.g., mass poisonings). Because its time dimension is uncertain or arbitrarily decided, it should probably not be described as a rate.
Birth rate A summary rate based on the number of live births in a population over a given period, usually 1 year.
Total fertility rate The average number of children that would be born per woman if all women lived to the end of their childbearing years and bore children according to a given set of age-specific fertility rates. It is computed by summing the age-specific fertility rates for all ages and multiplying by the interval into which the ages are grouped. The TFR is an important fertility measure, providing the most accurate answer to the question “How many children does a woman have on average”.
Net reproduction rate The average number of female children born per woman in a cohort subject to a given set of age-specific fertility rates, a given set of age specific mortality rates, and a given sex ratio at birth. This rate measures replacement fertility under given conditions of fertility and mortality: it is the ratio of daughters to mothers assuming continuation of the specified conditions of fertility and mortality. It is a measure of population growth from one generation to another under constant conditions. This rate is similar to the gross reproduction rate but takes into account that some women will die before completing their childbearing years. An NRR of 1.00 means that each generation of mothers is having exactly enough daughters to replace itself in the population. 