Final answer:
The researcher needs to maintain objectivity and avoid bias when conducting a case study, as the study depends on the researcher's unbiased observation and interpretation.
Step-by-step explanation:
When conducting a case study, it is particularly important that the researcher maintain objectivity and avoid bias. A case study is a detailed examination of an individual or a small group in a real-world context, and it's vital that the researcher observes and reports the case without letting personal views, predispositions or affiliations affect their judgment and analysis.
Unlike experimental designs, which can implement randomization to mitigate bias in the allocation of treatments, or large-scale surveys that can use random sampling to create a representative sample, a case study relies heavily on the researcher's ability to observe and interpret without bias. This includes following ethical constraints such as those set by institutional review boards (IRBs) that protect participants and maintain the integrity of the study.