Key Difference: Observational studies require the researcher to only observe the patients from far away and cannot interfere with the way they act. If a researcher interferes it could result in the data being manipulated. In clinical trails, the researcher would divide the participants into two more groups and control the way they behave, while noting the changes or results.

Observational studies and clinical trials are two different methods that researchers use to collect data and test theories. When conducting research, it is important for a researcher to be able to gather data by examining various subjects and being able to job down the outcome. Observational studies and clinical trials are different from each other in terms of interference of the researcher. In Observational studies, the researcher does not interfere, while in clinical trails the researcher creates two groups with controlled experimentation.

Observational studies require the researcher to only observe the patients from far away and cannot interfere with the way they act. If a researcher interferes it could result in the data being manipulated. In clinical trails, the researcher would divide the participants into two more groups and control the way they behave, while noting the changes or results. Observational studies are usually employed when dealing with data that does not require to be manipulated or data that is sensitive. Clinical Trials are usually used when testing some sort of products such as pills. In this three groups could be created one could be given the pill, another group a placebo and the third group nothing. The researcher would then jot down the changes or symptoms that the groups feel.

Clinical trials are an effective way to test new drugs and medical procedures that are being developed. However, the agencies have to make sure that the drugs do not have any critical side-effects. Both observational studies and clinical studies can range in size and can be used almost for all types of research. In observational studies the researchers observed the subjects and create hypothesis without assigning any treatments to the subjects. These are commonly used for conducting studies such as Does sleep affect daily activity? And How fast does smoking affect the lungs?

Both clinical trials and observational studies are used by many researchers to conduct experiments and determine what factors affect us in which way. This is mainly to understand more about out lives and how we are made.

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