Antiemetic

medications can prevent vomiting.

Histamine

I receptor antagonists can prevent vomiting, especially morning sickness,

although they can cause drowsiness and sedation.

Emetic

reflex is not vomiting reflex.

Emesis,

throwing up, and vomiting have the same meaning.

Double

blinding means that neither investigators nor patients know which study group

they belong to.

An

interventional study does not involve giving a piece of advice, a vaccine or medication.

Ecological

studies are particularly useful for comparing the health of populations in

different places or at different times.

A case

series study is aimed at describing the demographics, clinical presentations,

prognosis, and other characteristics.

Relative

risk is the main measurement used in a Cohort Study.

Case

series study did not contribute to the identification of HIV in the early

1980’s.