What is the difference between experimental and quasi-experimental design? When would it be appropriate to use each design?
Experimental design means that the subjects in the intervention have been randomly assigned to participate in the treatment or the control group. In a quasi-experimental design, there is no randomization. Experimental design is appropriate in research involving clinical trials where randomization is possible. The benefit is that it allows for factors such as demographics and socioeconomic status to be controlled for making generalization more likely. A quasi-experimental design make be seen in a more "natural" setting such as comparing two similar groups where one has an HIV prevention intervention in place and the other group does not. In this scenario, there it is not possible to randomize. This can present challenges when trying to determine the success or failure of the intervention, but can be controlled during the data analysis with statistics.
Describe the process of experimental design.
1. Select a topic. 2. Conduct a literature search. 3. Construct a hypothesis: Restate the research question in terms of the null and alternate hypotheses. 4.Determine the design of the research. 5. Determine the research methods. 6. Conduct the research and test the hypothesis. 7. Analyze the data. 8. Formulate conclusions. Determine if the data supports accepting or rejecting the null hypothesis.
What are the six hallmarks of cancer?
1) self-sufficiency of cells in signals controlling growth 2) loss of sensitivity to antigrowth signals 3) evasion of apoptosis ( e.g. mutation or loss of gatekeeper genes) 4) development of limitless replicative potential, usually via the expression of telomerase 5) sustained angiogenesis (formation of new blood vessels) which supplement the tumor's blood supply 6) tissue invasion and metastasis