The Low Prevalence Effect in Children

Alarming statistics reveal that 20 to 30 percent of cancers are missed in radiological screenings due to the perceptual challenge of finding low-prevalenceabnormalities such as this. A low prevalence item is anything that occurs infrequently. This phenomenon, known as the “low prevalence effect (LPE),” results in clinicians failing to identify a higher percentage of cancers in low-prevalence conditions compared to high-prevalence conditions, but can occur in any visual search task. This suggests that the behavioral responses of adults to low-prevalence conditions significantly contribute to diagnostic errors. While prior research has proposed that young children may be immune to this effect due to their distributed attentional style, our study is the first to empirically test this using an eye-tracking visual search task across child (aged 4 to 5 years) and adult populations. Results revealed that both children and adults demonstrated the LPE, as evidenced by decreased accuracy and slower search times during low-prevalence, target-present trials. These findings challenge earlier assumptions of children’s immunity to the low-prevalence effect, providing a more nuanced view of how developmental differences shape visual attention. These patterns indicate that children’s distributed attentional style may buffer them from the full extent of the LPE. Our study extends LPE literature to younger populations, offering an expanded developmental perspective and encouraging further research into how children's attentional strategies can be better understood and leveraged in real-world tasks.