What is one method to reduce investigator effects in research?

Implementing double-blind procedures is an effective method for reducing investigator effects in research. This approach ensures that neither the participants nor the researchers interacting with them are aware of which participants belong to the experimental group and which belong to the control group. By concealing this information, any biases or expectations from the researchers that could inadvertently influence the participants' behavior or response are minimized. This helps protect the integrity of the data collected, as the outcomes are less likely to be swayed by the subjective influence of the investigators.

In contrast, using a smaller sample size may actually increase the impact of variability and skew results, while providing detailed explanations to participants could inadvertently lead them to perform in a way that aligns with the researchers' expectations. Increasing the number of observers doesn’t necessarily equate to reducing investigator effects; if observers have preconceived notions or biases, those might still seep into the data collection process. Hence, double-blind procedures stand out as a robust method for reducing potential bias introduced by investigators.