Influence of thumb sucking on peer social acceptance in first-grade children.

Chronic thumb sucking in school-age children may reduce peer social acceptance, an important contributor to social development. The influence of thumb sucking on social acceptance was assessed among 40 first-grade children, who were shown four slides of two 7-year-old children (one boy, one girl) in two poses (one thumb sucking, one not). After viewing each slide in their classrooms, the children answered 10 numerically weighted questions related to peer acceptance. To limit the possibility that the children would determine the girl and boy were the same in each pose, the slide presentation was counterbalanced across two sessions 1 week apart. Using a repeated-measures analysis of variance, the authors compared composite scores on each question for both poses. The results indicate that while in the thumb-sucking pose, the children were rated as significantly less intelligent, happy, attractive, likeable, and fun and less desirable as a friend, playmate, seatmate, classmate, and neighbor than when they were in the non-thumb-sucking pose. These findings suggest that the risk of reduced social acceptance should be added to the list of potentially harmful effects of chronic thumb sucking in school-age children.