While case studies are more commonly used to generate and support hypotheses in psychology, they can also play a role in disproving or challenging existing theories or hypotheses. This is particularly true in situations where a case study reveals phenomena that cannot be explained by current theories, thereby highlighting their limitations or inaccuracies. For example, if a psychological theory predicts a certain behavior or mental process, and a case study provides clear evidence of an exception to this rule, it may prompt a reevaluation or modification of the theory. However, it is important to note that the disproving power of a case study is limited by its inherent lack of generalizability. A single case or a small number of cases may suggest exceptions to a theory, but broader research is typically required to formally disprove or significantly challenge established theories.

In case study research, particularly when dealing with sensitive topics, participant consent and confidentiality are of utmost importance. Researchers are obligated to obtain informed consent from participants, which means clearly explaining the purpose of the study, the procedures involved, any potential risks, and the participant's right to withdraw at any time without penalty. This consent must be freely given and can be withdrawn at any point. Regarding confidentiality, researchers take stringent measures to protect the identity and privacy of their subjects. This often involves anonymizing data, using pseudonyms, and ensuring that any identifiable information is not disclosed in published reports or discussions. In cases where revealing certain information is unavoidable for the integrity of the study, it is done with the utmost caution and ethical consideration, often with additional safeguards like additional consent forms or ethical reviews.

Reliability in case studies is a complex issue, primarily because of the in-depth, qualitative nature of these studies. To address reliability, researchers often employ detailed and systematic data collection and analysis procedures. This includes keeping thorough records of all data collected, using consistent methods throughout the study, and applying rigorous analytical techniques to ensure that the findings are as objective as possible. Peer review and triangulation with other data sources also enhance reliability. However, despite these efforts, case studies inherently have limitations in reliability compared to more quantitative research methods, due to the potential for researcher bias and the subjective interpretation of qualitative data. Consequently, while case studies provide valuable insights and in-depth understanding, their findings are often supplemented with other research methods to establish more reliable and generalizable conclusions in psychological research.

Triangulation in case study research refers to the use of multiple methods or data sources to enhance the credibility and validity of the findings. In psychology, triangulation plays a vital role in strengthening the conclusions drawn from a case study. By combining different methods, such as interviews, observations, and psychological assessments, researchers can obtain a more comprehensive and reliable understanding of the subject under study. This approach helps to offset the weaknesses inherent in each method when used alone, thereby providing a more balanced and nuanced view of the case. Triangulation also helps to reduce the potential for bias, as it allows for cross-validation of data. By converging findings from different sources or methods, psychologists can be more confident in the accuracy and robustness of their interpretations, making the case study a more powerful tool for understanding complex psychological phenomena.

Case studies contribute significantly to the development of psychological theories by providing in-depth and detailed data about individual cases or small groups. This rich data allows researchers to observe and document complex psychological phenomena that might not be evident in broader research studies. For example, Sigmund Freud’s psychoanalytic theory was largely developed based on insights from individual case studies. These studies offer a narrative that can illustrate how specific psychological principles play out in real-life scenarios. In addition, they often identify new variables or hypotheses that can be explored in more generalizable research. While they cannot establish cause-and-effect relationships due to their limited scope and potential biases, case studies provide a foundational understanding of psychological phenomena. This deep understanding is crucial for the formulation of theories that explain human behavior and mental processes.