Probability of some untoward event
Risk
Characteristics associated with an increased risk of becoming diseased
Risk factors
Period between exposure to a risk factor and the first manifestation of disease
Latency Period
A risk factor that is not a cause of disease is called a ______
Marker of disease
Determining how well a risk prediction tool correctly predicts the proportion of a group who would develop disease
Calibration
How to measure calibration of risk prediction tool?
Estimated number to develop disease / observed number who developed disease.
Ratio close to 1.0 means well calibrated
The accuracy of a risk prediction tool to identify which individuals will or will not have the disease.
Discrimination
This measures how often (in a given pair of random individuals) the risk prediction score was higher for the person with the disease?
Concordance Statistic (C-Statistic)
A useless toss coin-like tool has c-statistic of 0.5
A perfect tool has C-Statistic of 1
Best predictor of future major diseases?
Existing minor disease
Who noted that increased rate of cholera occured in people drinking water supplied by one source, and that epidemic subsided when said water supply was cut
John Snow
