Lecture 5 – HLTB15
- Incidence rate is over disease free person years.
- Person-years are the total number of grey bars for disease free.
- Standard Mortality ratio = Observed number of deaths per year/ expected number
of deaths per year (expressed as a percent!)
- Cause-specific mortality = number of deaths due to a particular disease /
population at risk (always whole population at risk) x 100
- Case-fatality = number of deaths due to particular disease / number of illness
associated with particular disease X 100
- Age standardization is an important predictor of mortality.
- With age comes higher prevalence with neurological disorders.
- Direct age adjustment: applying the rates of the population to a standard population
You need to have a standard population for a reference point (data
sets that have been compiled for specific age cohorts).
Yields the number of cases that would be expected if the age-specific
rates in the standard population were true for the study period.
(Equation) Direct Age Adjustment = total number of expected
numbers of deaths / population by the population at risk for the
standard population (population of specific age group you are
- We can use age standardization for mortality, incidence, and prevalence.
- Another way of standardizing is adding BOTH populations.
- Direct Method of Age Standardization
(PROBABLY WON’T BE ON THE EXAM… TOO HARD) Expected
deaths = age specific death rates per age category X standard
population (both populations together)