Internal validity refers to how well an experiment is done and how well a piece of individual research provides an investigator with an opportunity to choose among the different explanations of various aspects (Internal validity, n.d.). Altogether, internal validity helps to answer whether the research was correct.
External validity means the extent to which the results of a particular study could be used to analyze other situations or people (Types of fact, n.d.). It could also be defined as the valid generalization of specific data obtained in the course of the study.
Construct validity is often defined as the degree to which a specific test or approach measures or examines the notion or phenomenon which is taken as the main aim of the investigation. Construct validity is also an essential aspect of validity research.
Conclusion validity is the degree to which results of a particular study that are obtained in the course of an investigation are reasonable and could be used to continue the research.
Validity states the correlation between what is supposed to be measured and what is obtained in the course of the study, while reliability signals how consistently an experiment manages to bring specific results (Phelan & Wren, 2006).
Modern science has several types of research that could be used to obtain the needed results. These are non-experimental, quasi-experimental, and true experimental research designs. The first one could be defined as the approach that does not include any experiment that is conducted to support the main assumptions provided by the authors (What is research design? n.d.). For this reason, non-experimental research design uses other tools like survey, statistical analysis, etc. to collect the needed information and make an inevitable conclusion that is required in order to summarize the results of the research.
Quasi-experimental research design centers around a particular experiment that is created and conducted to provide researchers with credible information about the evolution of a specific issue or phenomenon (Experiments and Quasi-Experiments, n.d.). However, the adherence to this method means that not all aspects that might impact the phenomenon of interest could be controlled by an investigator. For this reason, his/her opportunities for interference are limited by the existing frames and limitations that do not result from the peculiarities of the suggested experiment.
Finally, the right experimental research design also focuses on the creation of a particular experiment that is needed to trace the evolution of a specific phenomenon, its most essential peculiarities, and other aspects that might impact the final results. The investigation is totally controlled. It means that an investigator is able to handle all factors and stressors that might have a significant impact on the researched notion, aspect, or phenomena (White & Sabarwal, 2014). This pattern often demands the creation of a specific environment that will be needed to gain control over the above-mentioned factors and guarantee the comprehensive investigation of the obtained results of the study.
If to compare the above-mentioned research designs, one should realize several essential facts. First, the main difference is in the approach to the research. When quasi and actual experimental methods imply the creation of a particular experiment, non-experimental one does not accept its necessity. Therefore, another difference is the ability to control the experiments behavior and all factors that might impact it. These differences predetermine the choice of one or another design to accomplish a specific task and attain success when investigating a phenomenon of interest that should be analyzed to obtain credible data.
References
Experiments and quasi-experiments. (n.d.). Web.
Internal validity. (n.d.). Web.
Phelan, C., & Wren, J. (2006). Exploring reliability in academic assessment. Web.
Types of validity. (n.d.). Web.
What is the research design? (n.d.). Web.
White, H., & Sabarwal, S. (2014). Quasi-experimental design and methods. Web.