Standardization and Life Tables Flashcards

1
Q

What is the mortality rate?

A

How many people die in a population in a given time period.

Number of death/Time period.

2
Q

What is life expectancy?

A

How old are people when they die?

Cohort’s LE calculated by averaging age of members when they die.

3
Q

What is age-specific mortality rate?

A

Mortality rate within certain age groups.

Number of deaths/time period for a certain age group.

4
Q

What is cause-specific mortality rate?

A

Mortality rate for a specific cause for a population.

Number of death/time period for a population and cause of death is specific.

5
Q

What is the number one confounder between mortality and populations?

A

Age.

6
Q

How does age confound?

A

Age structure of a population varies by:

Geography
Time
Risk Factor

7
Q

How can we account for age?

A

Two ways:
Stratification (age-specific mortality)

8
Q

What is direct age standarization?

A

Simulates two populations having same age structure.

Does not make age-specific mortality rates as comparable across populations since they would be the same.

9
Q

What is indirect standardization?

A

Simulates two populations having same age-specific mortality rates.

Makes age-specific death rates the same but you CANNOT compare age structures.

10
Q

How would you perform direct age adjustment?

A

Ex:

Unmarried men v married men.

Looks like death rate among married men is twice as much as unmarried men.

Step 1. Calculate age-specific and overall death rates.

Step 2. Create a standard population.

• Add the totals of the two populations to each other by age group. EX: Add group 1 20-30YO to group 2 20-30 YO
• This is standard population of unmarried and married men

Step 3. Apply death rate in each group to standard population to create “expected number of deaths” in each group
-Multiply death rate to standard population in each age group

Step 4. Calculate the age-standardized mortality rate

• Total number of expected deaths of population A/new total of standard population
• This results in AGE-STANDARDIZED MORTALITY RATE

Step 5. Compare the two

It allows us to equalize the number of people in age group.

11
Q

What is crude death rate?

A

Weighted average death rate across populations.
Calculated by:
SUM of [Each age specific death rate * number in each age group]
DIVIDED BY
Total population
It is also the number of death in the total population.

12
Q

How would you calculate indirect standardization?

A

Step 1.
Calculate expected number of deaths among group without death rate (Group B death rate)
-Use group A death rate and multiply by population for each age group in group B to get expected number of death in group B by age group.

Step 2.
Calculate the STANDARDIZED MORTALITY RATIO
-Number of recorded deaths in population B / number of expected deaths in population B

Step 3.
Interpret the standardized mortality ratio
-If SMR is 2.4 then the number of OBSERVED deaths among population B is 2.4 times higher than group A

13
Q

What are some pros of age-standardized mortality rates?

A

Powerful for comparing mortality in one population to another.

14
Q

Why is death a great indicator of health?

A

Case definition is straight-forward.
Everyone is at risk.
Information collected.

15
Q

When to use direct standardization?

A

When you have population size and number of deaths in each age group.

16
Q

When do you use indirect standardization?

A

When you have only death rate and not the size of the population.