Outdated websites since 30.12.2021

To receive our evidence-based self-help treatment manual "Free from BFRB", which teaches habit reversal training (developed by Azrin & Nunn) and decoupling (developed by our group), click https://ww3.unipark.de/uc/impulse_control/ — for more information read the below section

Body-focused repetitive behaviors (BFRB)

Excessive nail biting (biting one’s fingernails and/or the adjacent skin) and the compulsive pulling of one’s hair (trichotillomania) are impulse control disorders that are classified as BFRB.

Although the direct health consequences of nail biting are rarely severe apart from an occasional infection of the nail bed, the psychological consequences are often grave. Bitten nails are easily visible and often evoke disgust in other people. In the general population, nail biting is often equated with a nervous temperament and difficulty controlling impulsive behaviors. Many sufferers are ashamed to shake other people’s hands because of the appearance of their own hands. This may in turn prompt low self-esteem and social insecurity. Some patients try to hide their fingernails, which paradoxically makes the disorder even more conspicuous.

Full, thick hair is commonly associated with health, whereas bald or balding areas on the head or the lack of eyelashes and eyebrows (typical features of trichotillomania) are often mistaken for a severe somatic illness, such as cancer. People with trichotillomania are frequently ashamed of their appearance and conceal bald patches with caps, scarves, or wigs. In many cases, sufferers totally seclude themselves from their social environment, which substantially lowers their quality of life.

Pathological skin picking is another BFRB, and it is characterized by repetitive scratching, biting, and picking at the skin. Like the aforementioned behaviors, it is often associated with a low quality of life and can result in severe somatic problems.

If you are interested to learn about evidence-based treatment techniques (variants of decoupling, habit reversal training, stimulus control) to reduce excessive nail biting, skin picking and/or trichotillomania (hair pulling), please register here at no cost: https://ww3.unipark.de/uc/impulse_control
After you register (which is free and anonymous), you will receive our self-help manual "Free from BFRB" as a pdf-file.

Please donate
We provide the present as well as other self-help manuals at no cost. If you have benefited from the manual and/or would like to support our research, please consider making a donation. Donations of $20/20€ or more help us, for example, to create new self-help videos. You may donate online via this link, and you will receive an official receipt within a few days.

Preliminary research results on decoupling

Our group developed decoupling in 2010. A number of treatment studies have confirmed the efficacy of the approach (see the literature listed below). This effective and simple to learn intervention has recently been recommended in several meta-analyses and reviews, including a systematic review by Lee et al. in Frontiers in Behavioral Neuroscience (2019): “Throughout the review, we found evidence of benefit for ‘variants’ of HRT [habit reversal therapy], for example ‘movement decoupling’ (Moritz and Rufer, 2011)” (p. 13).


Lee, M. T., Mpavaenda, D. N. & Fineberg, N. A. (2019). Habit reversal therapy in obsessive compulsive related disorders: A systematic review of the evidence and CONSORT evaluation of randomized controlled trials. Frontiers in Behavioral Neuroscience, 13, 79. Link to article (full text)

Moritz, S., Penney, D., Ahmed, K. & Schmotz, S. (in press). A head-to-head comparison of three self-help techniques to reduce body-focused repetitive behaviors. Behavior Modification

Moritz, S., Rufer, M. & Schmotz, S. (2020). Recovery from pathological skin picking and dermatodaxia using a revised decoupling protocol. Journal of Cosmetic Dermatology, 19, 3038-3040. Link to article (full text)

Moritz, S., Treszl, A. & Rufer, M. (2011). A randomized controlled trial of a novel self-help technique for impulse control disorders: A study on nail-biting. Behavior Modification, 35, 468-485. Link to article (abstract)

Moritz, S. & Rufer, M. (2011). Movement decoupling: A self-help intervention for the treatment of trichotillomania. Journal of Behavior Therapy & Experimental Psychiatry, 42, 74-80. Link to article (abstract)

Weidt, S., Klaghofer, R., Kuenburg, A., Bruehl, A. B., Delsignore, A., Moritz, S. & Rufer, M. (2015). Internet-based self-help for trichotillomania: A randomized controlled study comparing decoupling and progressive muscle relaxation. Psychotherapy and Psychosomatics, 84, 359-367. Link to article (abstract)

Further information

In the media (selection)

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All my Family Care
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Cedar Sinai Hospital

For patients

For further information on trichotillomania, please visit the website of the TLC Foundation for Body-Focused Repetitive Behaviors (BFRB) at bfrb.org, which is a nonprofit organization based in the United States whose mission is to improve the quality of life of children, adolescents, and adults with trichotillomania and related body-focused repetitive behaviors such as skin picking. TLC works to raise awareness of these disorders, promote research and treatment advances, and provide information and support to sufferers and their families.


We would like to thank Jennifer Raikes, Executive Director of the TLC Foundation for Body-Focused Repetitive Behaviors, for her helpful comments on an earlier draft of the manual on decoupling.