1- When the same participants are used for both controls and experiments groups, it is call?

A) retrospective study

B) survey study

C) self-controlled study

D) Historical controlled study

2- The Framingham heart study is call?

A) A case series study

B) an experiment study

C) Longitudinal cohort study

D) Study of functional status

3- In randomized trials, a crossover design is?

A) one in which each subject receives tow or more treatment, but in different sequences.

B) case control study

C) Meta-analysis

D) one that examines the characteristics of subjects as one point in time.

4- A descriptive report of a small number of cases related to new virus is most likely a ?

A) case series study

B) cohort study

C) experimental

D) survey

5- Using historical controls is most appropriate when?

A) preliminary studies are needed

B) when a positive outcome is desired

C) when the objective is to establish efficiency of a treatment or procedure.

D) when multiple treatment are available

6- A retrospective cohort study uses?

A) current data

B) data collected before the onset of the study

C) looks at risk factors after an outcome has occurred

D) collect it as the expirement is conducted

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