intro to epi, study design Flashcards
“distribution” factors (3)
person, place, time
“determinant” factors (5)
physical, biological, social, cultural, behavioral
primary prevention, task of
preventing disease before it arises (immunization, improved nutrition), task of public health
secondary prevention, task of
early detection and prompt intervention, task of preventative medicine
tertiary prevention, task of
softening the impact of disease/impairment, task of rehabilitation (composes most of traditional medicine)
observational study designs, 2 types
no interventions/only observation
descriptive study (3)
describes existing relationships among variables (case reports, ecological studies, cross-sectional studies)
analytic study (2)
examines associations, possible casual relationships (cohort, case control)
experimental designs (2)
interventions attempted, clinical trials and community trials
infectivity
new cases/#susceptible (INS)
attack rate
clinically ill/#susceptible (ACS)
pathogenicity
developing illness/#exposed (PDE)
virulence
overt infection/#total infected (VOT)
case-fatality rate
deaths/#total cases
susceptible persons are-
not immune
evidence of exposure
+IgM
endemic
normal prevalence of disease for a given geographic area
hyperendemic
persistent high levels of disease in an area
sporadic
irregular/infrequent occurrence of disease
epidemic
unusual increase in cases above what is expected
outbreak
localized epidemic
cluster
aggregates of cases per place and time
pandemic
epidemic spread over countries/continents
incubation period
time between invasion and first symptoms
latent period
time between exposure and first symptoms
quarantine
separation of people who may have been exposed but are not symptomatic (well people)
isolation
separation for the period of communicability, for patients showing symptoms (sick people)
horizontal transmission
spread person to person via intimate contact
vertical transmission
spread mother to infant during childbirth or perinatal period
primary case
person who introduces disease into the group (not nec first diagnosed)
secondary case
person who develops disease from primary case
passive surveillance
relies on providers reporting to health department
active surveillance
providers are contacted by the health department on a regular basis for the collection of information
