cross-sectional study Flashcards
cross-sectional study aka
cross-sectional
prevalence study
we measure
cross-sectional
exposure and disease measures obtained at individual level AT SAME TIME
observation
cross-sectional
single period of observation
what is cross-sectional study good for
cross-sectional
good for hypothesis generation and to estimate magnitude and distribution of a health problem
start with
cross-sectional
- defined population
- gather data on exposure and disease
- 4 groups:
- exposed, have disease
- exposed, no disease
- not exposed, have disease
- not exposed, no disease
cross-sectional calculations use
cross-sectional
prevalence
prevalence of disease in exposed formula
cross-sectional
a/a+b
prevalence of disease in non-exposed formula
cross-sectional
c/c+d
prevalence of exposure in diseased
cross-sectional
a/a+c
prevalence of exposure in not diseased
cross-sectional
b/b+d
design: finding the sample
cross-sectional
- take sample of ppl. or households in a defined geographic area
- maybe defined by study question (occupational or regional exposure)
- random sampling of an area
measuring exposure
cross-sectional
questionnaires
records
lab tests
physical measurements
what factors are easily measured by cross-sectional studies
cross-sectional
factors that don’t change as a result of disease
EX: blood group
measurement of disease
cross-sectional
questionnaire for symptoms/diagnosis
physical exam
other tests (x-ray, mammography)
if possible, determine onset
need established diagnostic criteria
confounder
cross-sectional
factor related to risk factor or exposure of interest and to health outcome (disease status)
