Midterm Equations

Question 1

Crude birth rate

Answer 1

(births/midyear pop) * 1000

Question 2

Crude death rate

Answer 2

(deaths/midyear pop) * 1000

Question 3

Crude rate of natural increase

Answer 3

CBR - CDR

Question 4

Bookkeeping equation

Answer 4

P(t) = P(0) + B - D + I - O

Question 5

Linear growth

Answer 5

P(t) = P(0) + k*t

k = number added/year
t = number years

Question 6

Exponential growth

Answer 6

P(t) = P(0) + e^rt

Question 7

r

Answer 7

(1/t) * ln(Pt/P0)

Question 8

t

Answer 8

[ln(Pt/P0)]/r

Question 9

P(0)

Answer 9

P(t)/(e^rt)

Question 10

Doubling time

Answer 10

70/r%

Question 11

Age Specific Death Rate

Answer 11

(Da/Na) * 1000

Da = # deaths in age group a
Na = midyear pop in age group a

Question 12

Infant mortality

Answer 12

(# infant deaths a yr * 1000)/(# live births a yr)

ALSO = neonatal mortality + postneonatal mortality

Question 13

Under 5 mortality

Answer 13

(# births who die before 5th bday)/(births) * 1000

Question 14

Neonatal mortality

Answer 14

(D

Question 15

Post neonatal mortality

Answer 15

(D 1-11 months [1yr])/B *1000

Question 16

Maternal mortality ratio

Answer 16

(number of maternal deaths per year * 100,000)/(# live births per year)

Question 17

Maternal mortality rate

Answer 17

(# maternal deaths per year * 100,000)/(# of women at reproductive age)

Question 18

Cause specific death rate

Answer 18

(deaths attributed to cause C)/(population) * 100,000

ALSO = sum of all cause death rate and crude death rate

Question 19

Age Specific Fertility Rate

Answer 19

(Ba/Wa) * 1000

Ba = # births to women of age group a
Wa = # women of age group a

Question 20

Total fertility rate

Answer 20

= sum of ASFR * number of years in each age group

ex: 15-19 = 5 years –> multiply by 5

Question 21

number of maternal deaths

Answer 21

births * maternal mortality ratio

Question 22

Probability of contraception failure

Answer 22

P(failure in n years/mos/weeks) = 1 - P(no failure in n yrs/mos/weeks)

= 1 - [1 - P(failure in 1 time pd)]^n