Study Designs part3

?Advantages:
1.Suitable for rare diseases .
2.Results can obtained quickly.
3.Relatively inexpensive and short term study
4.Small sample size
5. Available data
6. No ethical problem
?Disadvantages of case control studies
1.Incidence or absolute risk cannot be determined directly from a case control study. Temporal relationship exposure-disease difficult to establish
2.Difficulty in selection the control.
3.Case- control study rely upon retrospective data which lead to recall bias.
4.Because the data are collected after the event (retrospectively) it is difficult to be whether correlation is causal or not.
5.Can not use to establish prevalence
?Advantages:
1.Suitable for rare diseases .
2.Results can obtained quickly.
3.Relatively inexpensive and short term study
4.Small sample size
5. Available data
6. No ethical problem
?Disadvantages of case control studies
1.Incidence or absolute risk cannot be determined directly from a case control study. Temporal relationship exposure-disease difficult to establish
2.Difficulty in selection the control.
3.Case- control study rely upon retrospective data which lead to recall bias.
4.Because the data are collected after the event (retrospectively) it is difficult to be whether correlation is causal or not.
5.Can not use to establish prevalence