Research Design Type (Research Methods and/or Statistical Methods) What are some of the most popular design types used to study your assigned topic? Research design types include case studies, statistical methods, simple design types based on a pretest, simple design types based on a control group, quasi-experiments, experiments, etc. (there are others, but these are the main ones). If your particular area of interest does not include quasi-experiments or experiments, emphasis is probably placed on a wide variety of statistical techniques including survey research analysis. Tell us about some of the techniques used in the papers that you have reviewed. All in all, what are some of the main threats to internal validity?