Intro to Epidemiology Notes
Just some notes from recitation class today:
Person Time = (in denominator)
Study Population = (in denominator) = person time (e.g. years)
Incidence = new cases (in numerator)
Initial data and post data = find midpoint (initial + post / 2, monthly data or average of all data)
Cumulative Incidence = measures population at risk for a certain exposure (numerator = new cases, denominator = everybody at risk – people who have disease already) Once measure that can be interpreted as a percentage.
Example of cumulative incidence; (0.2)(100) = 20%
Incidence Density = amount of time contributed to the study per person per time = individual case data is necessary to calculate incidence density. It is the most accurate way to calculate incidence (it involves how much time each participant contributed to study).
(Look in January notes for below) > look at the little book (review)
Case specific mortality = numerator = cases of death from disease, denominator = at risk of disease
Cause specific mortality = # of deaths from disease / population
Case fatality rate = # of deaths from disease / # of people with disease