STUDY DESIGN

STUDY DESIGN

1. DESCRIPTIVE

   • Case report
     • Odds ratio for rare disease
       • E.g Transplacental carcinogenesis
     • One case of unusual finding Retrospective Study
     • Advantages :quick and identify more than one risk factors in the same set of data Disadvantages :the past events may not be available
   • Case series
     • Multiple cases of finding similar diagnoses
     • Advantages: Hypothesis generation , established risk factors Disadvantages :cannot know causes and effect relationships
     • Rare diseases
       • Thalidomide
   • Descriptive study ( Cross Sectional studies )
     • Population - based Cases wit demominator Prospective
     • Chronic Condition ( prevalence)
       • Cancer
     • dvantaAges : Fast and inexpensive , can involve large sample size of study and can generate hypothesis Disadvantages : weak , unable to measure incidence and unknown disease occurred

2. Analytic

   • Observational
     • Cohort Study
       • To compared individual with exposure and without it. Prospective
       • Advantages: can determine outcome for each exposure and exposure adnd subject etermind before disease detection Disadvantages: DExpensive , time consuming and inefficient for rare disease.
       • Study the risk factor of disease
         • Framingham dheart diseased
     • Case Series Study
     • Cross Sectional Study
   • Experimental
     • Laboratory
     • Controlled Trials