Which of the following is cited as a bias in the evaluation of Little Hans?

Which of the following is cited as a bias in the evaluation of Little Hans?

• A. The father was already familiar with the research
• B. It showed universal applicability
• C. It had large population validity
• D. It used random sampling

Answer: (A)

The key idea is how the observer’s expectations and familiarity with the study can skew the data. In the Little Hans case, the father acted as the main source of information and interpretor of the child’s fantasies. Because he already knew Freud’s ideas and was closely involved, his reporting and the questions he chose could have been influenced by what he thought the researchers were looking for or by Freud’s theory. This kind of bias—observer/expectancy bias or demand characteristics—can color how events are described and interpreted, making the evidence seem to fit the theory more than it actually does. The other options describe general limits of a study’s generalizability or the method of selecting participants, which are important but not biases in the evaluation of the case data itself.

The key idea is how the observer’s expectations and familiarity with the study can skew the data. In the Little Hans case, the father acted as the main source of information and interpretor of the child’s fantasies. Because he already knew Freud’s ideas and was closely involved, his reporting and the questions he chose could have been influenced by what he thought the researchers were looking for or by Freud’s theory. This kind of bias—observer/expectancy bias or demand characteristics—can color how events are described and interpreted, making the evidence seem to fit the theory more than it actually does.

The other options describe general limits of a study’s generalizability or the method of selecting participants, which are important but not biases in the evaluation of the case data itself.