# **Supplemental Online Content**

Moritz S, Penney D, Missmann F, Weidinger S, Schmotz S. Self-help habit replacement in individuals with body-focused repetitive behaviors: a proof-ofconcept randomized clinical trial. *JAMA Dermatol.* Published online July 19, 2023. doi:10.1001/jamadermatol.2023.2167

**eAppendix.** Habit replacement manual

This supplemental material has been provided by the authors to give readers additional information about their work.

## Habit Replacement—A Technique to Reduce Body-Focused Repetitive Behavior Disorders (Skin Picking, Nail Biting, etc.)

#### Prof. Steffen Moritz, Stella Schmotz, & Birgit Hottenrott

## *Body-focused repetitive behavior disorders*

Nail biting, compulsive hair pulling (trichotillomania), skin picking, and lip-cheek biting (cavitadaxia) are referred to as body-focused repetitive behavior disorders (BFRBs) or body-focused impulse control disorder. In BFRBs, which occur in approximately 15% of the population, the person harms their own body by tearing, picking, squeezing, or otherwise damaging the skin, hair, mucous membrane, or nails. In this manual, we present a new technique to help reduce these behaviors. First, however, we explain the underlying rationale. Please do not skip the introduction as understanding the theoretical background of a technique has been shown to increase its effectiveness.

#### *Emotions and behavior*

Emotions such as sadness, anger, and joy are accompanied by typical facial expressions as well as other behaviors—for example, crying and slouching in sadness, narrowed eyes and tense posture in anger, or upturned corners of the mouth and a more upright head position in joy. This coupling of emotion and behavior is universal; it's the same for almost all people in all cultures. Since these emotion-related expressions and movements do not have to be specifically learned and may even be genetically transmitted, they are referred to as involuntary. Interestingly, this link works both ways. For example, simply lifting the corners of the mouth and glancing upward brightens the mood of many people, while a hunched-over gait often darkens the thoughts. If you don't believe this, give it a try!

In addition to these typical involuntary behaviors, other emotion-related (or emotionally induced) movement patterns are highly individual and can be roughly divided into self-directed (body-focused) and outward-directed movements. Emotions, whether positive such as joy or negative such as anger, are accompanied by an increased level of arousal, which is to a large extent released or regulated by these movements. In the case of an outwardly directed movement, the emotion might be expressed, for example, by a snort or a powerful blow on a table in anger. Many but not all people make such movements. In the case of joy, examples are a spontaneous raising of the arms, straightening your spine, clapping your hands, or other movements (such as raising a fist). People perform different movement patterns depending on the occasion. These movements are thus not universal, unlike the involuntary behavior described in the previous paragraph.

You may be wondering what this has to do with BFRBs. People with BFRBs report that their emotions frequently trigger nail biting and other undesired behaviors. The repertoire of motor excitation or emotion regulation in BFRBs is typically restricted and is not directed outward, as in the examples above, but is primarily related to one's own body. Anger, boredom, and other emotions break through in the form of picking, biting, or pulling on one's own body parts.

#### *Mixed feelings*

A high level of ambivalence, or mixed feelings about the behavior, is characteristic for people with BFRBs. On the one hand, those affected suffer a great deal from their behavior, especially from the long-term consequences, which can be serious in the case of hair pulling (e.g., bald patches, hair growth disorders) or skin picking (scars) and are often accompanied by feelings of shame. On the other hand, the behavior also gives a feeling of release and satisfaction by relieving tension or of "killing time" when bored (for example, by symmetrically rounding all one's fingernails in a certain way or "hunting" for certain hairs). The behavior is often accompanied by pleasurable feelings that are rarely openly acknowledged because the behavior is deemed inappropriate by most people and society in general. These positive, immediate feelings are an important factor in maintaining the behavior patterns.

BFRB behavior can be intentional or can take place automatically; the latter form is more common. In either case, individuals are unable to stop the harmful behavior.

The technique presented here replaces the harmful automatic habit with a behavior that is both harmless and unobtrusive.

## *Characteristics of BFRBs*

BFRBs, as already noted, are characterized by damage to the hair, skin, lips, cheeks, or nails. Approximately 50% of affected individuals exhibit at least two of the behaviors simultaneously. Nail biting, hair pulling, skin picking, and lip-cheek biting may seem very different, but they share the following characteristics:

1. The execution rarely varies—it takes place in a quite stereotypical way. Most of the time, for example, only certain parts of the skin are picked, only certain hairs are pulled out (e.g., gray or split hairs), and the movements that lead to, for example, nail biting remain virtually the same across different situations and episodes.

2. The movements are mostly performed with some pressure (sometimes even auto-aggression), such as when the fingers scan the skin for irregularities or the tongue or teeth scan the oral mucosa during lip-cheek biting. The movements often reflect the triggering emotion (e.g., scratching in the case of anger, perfectionistic "modeling" in the case of boredom) and serve mainly to release tension, i.e., to regulate the emotions to a lower level of arousal.

# *That's all well and good, but what does this actually mean for treatment?*

The idea behind habit replacement is to substitute the automatic, stereotyped, and harmful movement patterns of the BFRBs for another pattern, one that is also automatic but is inconspicuous and, most importantly, harmless. The new movement should be a behavior that is not in itself harmful and that can even be regarded as normal or common (please note that practically all people "jiggle" their hands, feet or other body parts a little when excited or feeling another strong emotion). However, it is necessary to practice the new movements before they can become automatic. Therefore, it's important that you regularly perform the exercises taught in the following section (see also https://clinical-neuropsychology.de/habit-replacement-en/) and do not get frustrated by small setbacks and give up. Think of these as events or incidents that you can learn from; people are often not aware of exactly what their fingers, tongue, etc., are doing when they are nervous or bored. Setbacks often lead to such insights.

# © 2023 American Medical Association. All rights reserved.

#### *Habit replacement: New habits for taking care of yourself*

Circular movements are helpful as a replacement for BFRBS because they become easily automatic. For example, move the tip of your thumb in a circle around the tip of your index finger or cross your arms and move your fingertips in a circle on your forearms. Try it out. If you tend to inspect and later pick at "imperfect" areas of your skin, it may be helpful to perform circular motions with your fingers on your clothing or on areas of the body that you do not typically pick at (e.g., the crook of your arm). **To be sure your movements are inconspicuous, make only small circles. Alternatively, you can lightly tap your fingers on your skin. If you wear rings, you may also involve these.** 

What else? The movement itself—especially if it is performed quite quickly—helps to calm down your bodily reactions to strong emotion (remember, only a few people manage to stay "cool" in the face of strong emotions). Unlike harmful BFRBs, the new movement should be a light stroking of the skin. If you are comfortable with this (not all people with BRFB will find this comfortable), feel free to consciously evoke positive feelings.

# Watch a video demonstration of these suggested movements here: https://clinicalneuropsychology.de/habit-replacement-en/

As soon as you catch yourself doing the target behavior (e.g., skin picking) or notice one of the triggering emotions or a feeling of tension, do a habit replacement movement. The key steps are as follows:

1. Make small, circular movements (e.g., with your fingers on your pants or a sleeve, with the fingertips of one hand on the opposite forearm). You can make a circle or choose another movement pattern (e.g., such when making a figure 8 on your arm), but it should be as simple as possible so it can become second nature. Alternatively, you can gently drum your fingers (see video).

2. The movement should be soft and light so that it does not result in damage and does not put pressure on the skin, nail, etc. Perform the movement as needed, quickly but without pressure or nail contact with your skin. Try your best to associate the new movement with a positive feeling; try to enjoy the gentle movement.

3. Beyond BFRBs, avoid touching your body with your hands, feet, teeth, or tongue in ways that are jerky, exert too much pressure, or cause pain, such as by brushing your teeth too hard or roughly scrubbing your skin too hard in the shower. You will not always succeed in avoiding this. That is OK; no one succeeds at this all the time. Do not punish yourself if you fail. Instead, calmly redirect yourself to making gentle movements when you notice this happening. Think of the exercises as a process that not only reduces BFRBs but also leads to more self-care (perhaps even self-love) and mindfulness.

You may be wondering why you should gently stroke your arm if your main problem is lip-cheek biting or nail biting. This is because BFRBs have a tendency to generalize; this is also why most sufferers perform several of the harmful movements at the same time. The suggested movement is also intended as prevention. Since movements and body processes are closely linked, it is helpful to touch your body gently in areas different from the problematic movement.1 This can favorably influence the problem movement itself via physical feedback processes.

<sup>1</sup> Do the following experiment: Breathe through your nose (mouth closed) a few times and then through your mouth a few times. How does your belly feel each time? Most people report that their belly is looser when their mouth is open. This is one of many examples of how movements and muscle tone can spread from one part of the body to another.

In addition to trying the habit replacement technique presented here, think about other ways to do something good for your body. Treat yourself to a massage, take a bath, and afterwards apply some lotion both consciously and, ideally, lovingly.

The new movement must be practiced to become second nature. The first few days will likely be bumpy, with frequent setbacks. Be kind to yourself when you notice that the behavior you're trying to unlearn has returned. Simply interrupt the action and perform habit replacement by, for example, lovingly instructing your hand to perform the new movements instead of, for example, scratching your skin. Practice makes perfect. If you have areas of skin that are itchy, feel free to cover them with a soothing cream. You should not touch scars or areas with rough skin. If the urge is too great, circle the area with your fingers with no pressure or make the movements on your clothing.

Be sure to also set your smartphone alarm clock (timer) for at least two times per day (preferably times when you often perform the undesired behavior (for example, in the evening when you are watching TV) to remind yourself of the exercise. Be sure to practice the new movements in times when you are not feeling stress as well so that the movements are increasingly incorporated into your natural behavioral repertoire.

The habit replacement exercise achieves several goals at once. It prevents or takes the place of BFRBs, and it also helps to take the edge off strong emotions, which most people need at times. Ideally, the new movement is associated with a positive emotion due to the gentle movements.

Please note:

- Do not pick or bite off sore or rough or disturbing skin areas (e.g., hangnails). Instead, remove them with appropriate tools, such as nail files or nail clippers, and disinfect the skin if necessary.

- Pay attention to whether the pressure you are exerting on your skin gradually increases over time. If so, counteract this by consciously returning to a gentler touch.

- Don't forget to watch the video and identify suitable movements for yourself (e.g., a gentle circling or drumming of the fingers): https://clinical-neuropsychology.de/habit-replacement/

JAMA Dermatology

<jats:sec><jats:title>Importance</jats:title><jats:p>Body-focused repetitive behaviors (BFRBs; eg, skin picking) encompass a set of conditions at the interface of dermatology and psychiatry/psychology. The disorder is prevalent but currently underdiagnosed and undertreated.</jats:p></jats:sec><jats:sec><jats:title>Objective</jats:title><jats:p>To compare a new self-help intervention, habit replacement, against a wait-list control condition for the treatment of BFRBs.</jats:p></jats:sec><jats:sec><jats:title>Design, Setting, and Participants</jats:title><jats:p>This randomized clinical trial was conducted online in 2022. Participants were a population-based nonclinical sample with BFRBs and were recruited via social media. Initially, 481 individuals entered the assessment; 213 were excluded blind to results. A final sample of 268 participants were randomized. The intervention period was 6 weeks.</jats:p></jats:sec><jats:sec><jats:title>Interventions</jats:title><jats:p>Participants were randomized to a self-help intervention, habit replacement, or a wait-list control condition (each n = 134).</jats:p></jats:sec><jats:sec><jats:title>Main Outcomes and Measures</jats:title><jats:p>The Generic BFRB Scale-45 (GBS-45, self-report) represented the primary outcome.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Individuals in the 2 conditions (n = 268; 241 [89.9%] women; mean [SD] age, 36.8 [11.1] years; skin picking, 68.3%; trichotillomania, 28.4%; nail biting, 36.6%; lip-cheek biting, 26.1%; other, 20.1%) did not differ on any baseline characteristics. The experimental group significantly improved on the primary outcome (GBS-45) for both the per-protocol (technique was used at least once weekly, η<jats:sub>p</jats:sub><jats:sup>2</jats:sup> = 0.068, <jats:italic>P</jats:italic> = .001) and the intention-to-treat analyses relative to the wait-list control group (expectation–maximization algorithm; η<jats:sub>p</jats:sub><jats:sup>2</jats:sup> = 0.019, <jats:italic>P</jats:italic> = .02). The interaction of group and time yielded statistical trends in favor of the experimental condition only on the Patient Health Questionnaire-9 and quality of life. For the Clinical Global Impressions scale, more individuals in the habit replacement group reported improvement (52.8% vs 19.6%; <jats:italic>P</jats:italic> &amp;amp;lt; .001). User satisfaction in the habit replacement group was high. Moderation analyses that included all baseline variables showed that those who exhibited nail biting particularly benefited from the new technique.</jats:p></jats:sec><jats:sec><jats:title>Conclusions and Relevance</jats:title><jats:p>The present proof-of-concept randomized clinical trial tentatively demonstrates that habit replacement is a feasible and effective self-help strategy against BFRBs, especially for nail biting. Study limitations include the lack of external assessment and verified diagnoses. In addition, the study is missing follow-up data. Self-help habit replacement shows promise in reducing BFRBs but not concomitant symptoms.</jats:p></jats:sec><jats:sec><jats:title>Trial Registration</jats:title><jats:p>German Clinical Trials Register Identifier: <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="https://drks.de/search/en/trial/DRKS00030511">DRKS00030511</jats:ext-link></jats:p></jats:sec>

A near fatal case of pathological skin picking.

Am J Case Rep

Characteristics of trichotillomania and excoriation disorder across the lifespan.

Psychiatry Res

A randomized controlled trial of a novel self-help technique for impulse control disorders: a study on nail-biting.

Behav Modif

Habit reversal training and variants of decoupling for use in body-focused repetitive behaviors: a randomized controlled trial.

Cognit Ther Res

Internet-based self-help for trichotillomania: a randomized controlled study comparing decoupling and progressive muscle relaxation.

Psychother Psychosom

Evaluating the duration of the competing response in habit reversal: a parametric analysis.

J Appl Behav Anal

A comparison of contingent vs non-contingent competing response practice in the treatment of nervous habits.

J Behav Ther Exp Psychiatry

The knowledge, awareness, and practice patterns of dermatologists toward psychocutaneous disorders: results of a survey study.

Int J Dermatol

Body-focused repetitive behaviors: more prevalent than once thought?

The Generic BFRB Scale-8 (GBS-8): a transdiagnostic scale to measure the severity of body-focused repetitive behaviours.

Behav Cogn Psychother

Effect of internet-based vs face-to-face cognitive behavioral therapy for adults with obsessive-compulsive disorder: a randomized clinical trial.

JAMA Netw Open

Internet-based cognitive behavioral therapy for depression: a systematic review and individual patient data network meta-analysis.

JAMA Psychiatry

Body-focused repetitive behaviors (BFRBs; eg, skin picking) encompass a set of conditions at the interface of dermatology and psychiatry/psychology. The disorder is prevalent but currently underdiagnosed and undertreated.
To compare a new self-help intervention, habit replacement, against a wait-list control condition for the treatment of BFRBs.
This randomized clinical trial was conducted online in 2022. Participants were a population-based nonclinical sample with BFRBs and were recruited via social media. Initially, 481 individuals entered the assessment; 213 were excluded blind to results. A final sample of 268 participants were randomized. The intervention period was 6 weeks.
Participants were randomized to a self-help intervention, habit replacement, or a wait-list control condition (each n = 134).
The Generic BFRB Scale-45 (GBS-45, self-report) represented the primary outcome.
Individuals in the 2 conditions (n = 268; 241 [89.9%] women; mean [SD] age, 36.8 [11.1] years; skin picking, 68.3%; trichotillomania, 28.4%; nail biting, 36.6%; lip-cheek biting, 26.1%; other, 20.1%) did not differ on any baseline characteristics. The experimental group significantly improved on the primary outcome (GBS-45) for both the per-protocol (technique was used at least once weekly, ηp2 = 0.068, P = .001) and the intention-to-treat analyses relative to the wait-list control group (expectation-maximization algorithm; ηp2 = 0.019, P = .02). The interaction of group and time yielded statistical trends in favor of the experimental condition only on the Patient Health Questionnaire-9 and quality of life. For the Clinical Global Impressions scale, more individuals in the habit replacement group reported improvement (52.8% vs 19.6%; P < .001). User satisfaction in the habit replacement group was high. Moderation analyses that included all baseline variables showed that those who exhibited nail biting particularly benefited from the new technique.
The present proof-of-concept randomized clinical trial tentatively demonstrates that habit replacement is a feasible and effective self-help strategy against BFRBs, especially for nail biting. Study limitations include the lack of external assessment and verified diagnoses. In addition, the study is missing follow-up data. Self-help habit replacement shows promise in reducing BFRBs but not concomitant symptoms.
German Clinical Trials Register Identifier: DRKS00030511.

Self-Help Habit Replacement in Individuals With Body-Focused Repetitive Behaviors: A Proof-of-Concept Randomized Clinical Trial.

Self-Help Habit Replacement in Individuals With Body-Focused Repetitive Behaviors

Self-Help Habit Replacement in Individuals With Body-Focused Repetitive Behaviors

Clinical Summary

What was studied

Key findings

Study limitations

Clinical implications

Related Questions