1. Minimizing bias and decreasing threats to internal validity is important to experimental designs. How will a researcher use manipulation, randomization, and control to minimize bias and decrease threats to internal validity?
Experimental designs use elements such as randomization, manipulation, and control to minimize bias and decrease threats to internal validity. Manipulation involves research purposefully altering a variable within the research environment to determine the effect of the change (Bhattacherjee, 2012). Control, however, focuses on preventing external factors from influencing a research outcome. Randomization ensures all the participants or variables have a fair chance of selection to any treatment or group prior to the research study. Control and randomization determine the effect of the manipulation of the factor while minimizing any internal or external biases and influences. Based on definition, the concepts clearly help decrease various threats to internal validity.
2. Researchers say randomized clinical trials (RCT) provide the strongest level of evidence for an individual study in an evidence-based model. As a consumer of research, do you think this statement is true? Why or why not?
According to many researchers, randomized clinical trials (RCT) provide the strongest level of evidence for an individual study when using an evidence-based model. This is because randomized clinical trials prevent selection errors and bias. Randomized clinical trials ensure all the participants’ systematic differences, which are likely to influence the outcome of the study, have equal distribution between the study groups (Kimachi et al., 2020). Therefore, outcome differences can be attributed to the treatment rather than a selection of participants. This makes RCT ideal to provide the strongest level of evidence for individual studies when using evidence-based models.
3. In an experimental design, how does intervention fidelity increase the strength and quality of evidence provided by study findings?
During experimental designs, researchers may use intervention fidelity to increase the strength and quality of the evidence from a study outcome. According to Melnyk and Morrison-Beedy (2018), intervention fidelity is the extent that the intervention is delivered as it was intended. Intervention fidelity decreases threats to the internal validity of a research study, simplifying analysis and discussion of research findings. In addition, the use of intervention fidelity aids in determining if variations in findings arise from the intervention itself or the method used to carry out the intervention.
4. What is your Cosmic Question? (This is a question you will ask your peers to respond to based on this week’s topic of Quantitative Research.)
Reliability and validity both measure research findings. What are the differences between reliability and validity?