Biased Confidence in Risk Assessment Studies

The present research examined factors that influence laypeople's confidence in the results of risk assessment studies. A 2 (hazard; cell phone, base station) × 2 (study outcome; no risk, risk) × 2 (health effect; well-being, cancer) × 3 (risk perception prior to the manipulation; low, medium, high) design was used. Results showed that participants had more confidence in studies with results that were in line with their prior attitudes compared with studies that were at odds with their prior attitudes. In addition, participants had more confidence in studies showing a risk compared with studies showing no risk. Results suggest that these biases may be one of the reasons why laypeople are concerned about technological risks, even when risk assessment studies indicate that there is a low probability of adverse health effects.