Case study research involves an in-depth study of an individual or group of indviduals. Case studies often lead to testable hypotheses and allow us to study rare phenomena. Case studies should not be used to determine cause and effect, and they have limited use for making accurate predictions. There are two serious problems with case studies — expectancy effects and atypical individuals. Expectancy effects include the experimenter’s underlying biases that might affect the actions taken while conducting research. These biases can lead to misrepresenting participants’ descriptions. Describing atypical individuals may lead to poor generalizations and detract from external validity. Survey Method
In survey method research, participants answer questions administered through interviews or questionnaires. After participants answer the questions, researchers describe the responses given. In order for the survey to be both reliable and valid it is important that the questions are constructed properly. Questions should be written so they are clear and easy to comprehend. In addition to the methods listed above some individuals also include qualitative (as a distinct method) and archival methods when discussing descriptive research methods.