Study Designs part4

?Advantages of Cohort studies
1.They allow complete description of the individuals experience subsequent to exposure .
2.They provide clear temporal sequence of exposure and disease.
3.They provide excellent opportunity to study rare exposures.
4.They permit the assessment of multiple outcomes that may be relate to the same risk factor.
5.They permit the direct assessment of risk of exposure and disease development .
6.Less chance of bias .
?Disadvantages of Cohort studies
1.Not suitable for rare disease.
2.Long – term follow up may be needed when the latency period for outcome of interest is long .
3.Attrition or loss of people from the sample during the course of the study.
4.Time consuming .
5.Expensive .
6.The exposure status may change during the conduct of the study
?Disadvantages of Cohort studies
1.Not suitable for rare disease.
2.Long – term follow up may be needed when the latency period for outcome of interest is long .
3.Attrition or loss of people from the sample during the course of the study.
4.Time consuming .
5.Expensive .
6.The exposure status may change during the conduct of the study