Module 2 Definitions Flashcards
Sufficient cause
A minimum set of conditions without one of which the disease would not occur.
Component cause
A factor that contributes towards dis-ease causation, but is not sufficient to cause disease on its own.
Necessary cause
A factor or component cause that must be present for the disease to occur.
Primary Prevention
Limits the occurrence of disease by controlling specific causes and risk factors
Secondary Prevention
Reduces the most serious consequences of disease
Tertiary Prevention
Reduces the progress of complications of the established disease.
Screening
Identifying risk factors for disease or unrecognised disease by applying tests on a large scale to a population.
Sensitivity
The likelihood of a positive test in those with the disease.
Specificity
The likelihood of a negative test in those without the disease
PPV
The probability to having disease if the test is positive.
NPV
The probability of not having the disease if the test is negative
Lead time bias
The apparent increase in life expectancy / lead time due to early detection of disease
Length time bias
Calculating mean survival from screened patients gives the impression of longer average survival that occurs in the population
Attributable risk
The amount of extra disease attributable to a particular risk factor in the exposed group.
Population attributable risk
The amount of extra disease attributable to a particular risk factor in a particular population.