Evaluating the Efficacy of Habit Reversal: Comparison With a Placebo Control

Background: The purpose of this study was to compare the effectiveness of habit reversal with a placebo control as a treatment for chronic nail biting in adults.

Method: Thirty adults with a chronic nail-biting problem (occurring >=5 times/day nearly every day for >=4 weeks and causing physical damage or social impairment) were randomly assigned to a placebo control or habit reversal group. Five participants withdrew from the study prior to the completion of treatment. The remaining individuals in both groups received a total of 2 hours of treatment over 3 sessions. Individuals in the habit reversal group (N=13) received the components of awareness training, competing response training, and social support. Individuals in the placebo control group (N=12) simply discussed their nail biting. At pretreatment, posttreatment, and a 5-month follow-up, nail length was measured, photographs were taken of the damaged nails and later rated by independent observers, and data on participant depression, anxiety, and self-esteem were obtained. Treatment compliance and acceptability data were collected at posttreatment only.

Results: Results showed that habit reversal produced a greater increase in nail length at posttreatment and follow-up when compared with the placebo. Data from the independent raters confirmed these findings. Habit reversal was also viewed as a more acceptable intervention by the participants. At posttreatment, the habit reversal group had increased their nail length by 22% from pretreatment compared with a 3% increase for the placebo group. At follow-up, the habit reversal group maintained a 19% increase in nail length from pretreatment compared with a 0% increase for the placebo group.

Conclusion: Findings from this study suggest habit reversal is more effective than a placebo control and should be considered a well-established intervention for body-focused repetitive behaviors.