morbidity and mortality Flashcards
median age
age at which half the population is younger and half the population is older
dependency ratio
non-working persons(0-14,65+)/working persons x 100
crude birth rate
births/population
crude death rate
deaths/population
demographic transition stages (I-IV)
I- high CBR, high CDR (pre-industrial)
II- high CBR, declining CDR (less developed countries)
III/IV- low CBR, low CDR (developed countries)
population pyramid shapes for rapid growth, slow growth, negative growth
rapid- pointed triangle
slow- broad based triangle
negative growth- inverted triangle
which population pyramid type does US fit?
slow growth
characterisitics of a country with rapid growth
many in younger cohorts, but few survive to old age
characterisitics of a country with slow growth
birth rates approximate death rates
characterisitics of a country with negative growth
birth rates are less than death rates
count
raw estimate of disease frequency at one point in time, denominator is unknown
proportions
numerator is part of denominator, range from 0-1, often expressed as a percentage
rate differs from proportion in that it includes-
a unit of time in the denominator
3 types of rates
crude, category-specific, characteristic-adjusted
crude rate
unadjusted for other factors, includes entire population
category-specific
adjusted and denominator only includes people in that category
most mortality data in the US is obtained from
death certificates
mortality rate
estimation of the portion of the population that dies during a specific period
denominator for mortality rate=
persons at risk of dying, estimate using mid-year population
disease
physiologic or psychologic dysfunction
illness
subjective state- patient feels aware of not being well
sickness
social dysfunction assumed by patient when not well
morbidity
any departure from physiologic or psychologic well-being
incidence
frequency of a new event, requires duration
incidence is more important when discussing ___ of disorder
etiology
units for incidence
person-time
incidence rate
new events in a defined period/population at risk of experiencing event during defined period
prevalence
frequency of an existing event
prevalence is useful for assessing ___
societal burden
a question asking “have you ever had X disease?” is ___ prevalence
period (period = your life)
what is standardization?
techniques to remove effects of differences/other confounding variables
direct method of standardization
(rate of disease in B x population in A)+…/total population
indirect method
uses SMR
what is SMR?
standardized mortality ratio- deaths observed in study/expected deaths in study if rate same as standard population
proportional mortality ratio
proportion of observed deaths from a specific condition/proportion of deaths expected from that condition in a standard population
YPLL
years of potential life lost
QALYs
quality-adjusted life years- estimate of remaining life free of impairment, disability or handicap
impairment
loss of normal function
disability
restrictions stemming from impairment
handicap
disadvantages due to disability or impairment
DALYs
disability adjusted life years- years of life lost due to premature mortality+years of life lies with disability
