Which of the following is NOT a type of research design discussed?

The correct response identifies that a case study design is indeed a recognized type of research design, used primarily in qualitative research to provide an in-depth understanding of a single case or a small number of cases. This design allows for the exploration of complex issues within real-life contexts and can be particularly useful in applied fields such as clinical psychology, where individual differences and contextual factors are important.

In contrast, the other designs listed—cross-sectional, longitudinal, and successive independent sample designs—are commonly discussed in research methodology. Cross-sectional design involves observing a population at a single point in time, making it useful for identifying patterns or relationships between variables at a specific moment. Longitudinal design, on the other hand, involves repeated observations of the same variables over long periods, enabling researchers to track changes and developments over time. Lastly, successive independent samples design refers to a methodology where different samples are collected at different times to infer trends or patterns without following the same subjects.

These methodologies play crucial roles in the social sciences and psychology, each serving different research questions and objectives. Understanding these various designs is fundamental for any research-oriented field, especially in clinical psychology, where different designs can impact how data is interpreted and applied in practice.