Cross-sectional

Cross-sectional

1. Non-directional

   • exposure and disease status are observed at the same time
     • fixed point

2. Advantages

   • representitive of the general population
   • convenient and inexpensive
   • can evaluate several exposures and diseases

3. Disadvantages

   • only works with existing or prevalent cases not incidence
   • can only include cases that survive long enough
     • possible survival bias
   • short duration or common diseases are often under-represented

4. describes patterns of disease occurance

5. generates hypothesis