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| Advantages | Disadvantages |
| One case to initiate a signal (case report) | No control (uncontrolled) |
| Provide stronger evidence with multiple cases (cases series) | Difficult to compare different cases |
| Observational | Cases may not be generalizable |
| Educational | Selection bias |
| Easy to do (fast and no financial support needed) | Unknown future outcome/follow-up |
| Identify rare manifestations of a disease or drug |
