<prompt> Exposure to multiple outcomes can be studied inCoho studyCase control studyCross sectional studyEcological study  <response>: In Coho study, multiple outcomes can be studied together. In Case control study, multiple exposures can be studied together. COHO STUDY: Time consuming expensive study Incidence RR can be calculated No recall bias Ethical problems are present is not useful for rare diseases Loss of follow-up can be seen - max allowable attrition rate is 5 ; ideal retention rate 95 HAWTHORN BIAS - study subjects alter their behavior without notice ; can be seen. 