What is the function of nail biting: An analog assessment study

Objective To compare the frequency of nail biting in 4 settings (interventions) designed to elicit the functions of nail biting and to compare the results with a self-report questionnaire about the functions of nail biting. Design Randomised allocation of participants to order of conditions. Setting University Psychology Department. Subjects Forty undergraduates who reported biting their nails. Interventions Left alone (boredom), solving maths problems (frustration), reprimanded for nail biting (contingent attention), continuous conversation (noncontingent attention). Main Outcome measures Number of times the undergraduates bit their nails. Results Nail biting occurred most often in two conditions, boredom and frustration. Conclusion Nail biting in young adults occurs as a result of boredom or working on difficult problems, which may reflect a particular emotional state. It occurs least often when people are engaged in social interaction or when they are reprimanded for the behavior.