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One of the most effective methods that can be used by researchers to avoid sampling bias is simple random sampling, in which samples are chosen strictly by chance. This provides equal odds for every member of the population to be chosen as a participant in the study at hand.
How diseases happens to spread in communities is the direct contact of bacteria, viruses or other germs from one person to another. This can happen when an individual with bacterium or virus touches, kisses, or coughs on someone who isn’t infected.
