Practitioner Review: Assessment and treatment of body dysmorphic disorder in young people.

Body dysmorphic disorder (BDD) is a relatively common and highly impairing mental disorder that is strikingly underdiagnosed and undertreated in Child and Adolescent Mental Health Services (CAMHS). The only clinical guidelines for the management of BDD in youth were published nearly 20 years ago, when empirical knowledge was sparse. Fortunately, there has been a surge in research into BDD over the last 10 years, shedding important insights into the phenomenology, epidemiology, assessment and treatment of the disorder in young people. This review aimed to provide an overview of recent research developments of relevance to clinicians and healthcare policymakers. We summarise key findings regarding the epidemiology of BDD in youth, which indicate that the disorder usually develops during teenage years and affects approximately 2% of adolescents at any one point in time. We provide an overview of aetiological research, highlighting that BDD arises from an interplay between genetic and environmental influences. We then focus on screening and assessment strategies, arguing that these are crucial to promote detection and diagnosis of this under-recognised condition. Additionally, we summarise the recommended treatment approaches for BDD in youth, namely cognitive behaviour therapy with or without selective serotonin reuptake inhibitors. The review concludes by highlighting key knowledge gaps and priorities for future research including, but not limited to, better understanding aetiological factors, long-term consequences and treatment.

Intentional Self-Harm and Death by Suicide in Body Dysmorphic Disorder: A Nationwide Cohort Study.

BACKGROUND: Body dysmorphic disorder (BDD) is thought to be associated with considerable suicide risk. This nationwide cohort study quantified the risks of intentional self-harm-including nonsuicidal self-injuries and suicide attempts-and death by suicide in BDD. METHODS: Individuals with a validated ICD-10 diagnosis of BDD in the Swedish National Patient Register, registered between January 1, 1997, and December 31, 2020, were matched with 10 unexposed individuals (i.e., without BDD) from the general population on birth year, sex, and county of residence. Conditional Poisson regression models estimated incidence rate ratios and 95% CIs for intentional self-harm. Stratified Cox proportional hazards models estimated hazard ratios and 95% CIs for death by suicide. Models adjusted for sociodemographic variables and lifetime psychiatric comorbidities. RESULTS: Among 2833 individuals with BDD and 28,330 unexposed matched individuals, 466 (16.45%) and 1071 (3.78%), respectively, had at least 1 record of intentional self-harm during the study period (incidence rate ratio = 3.37; 95% CI, 3.02-3.76). In the BDD group, about two-thirds (n = 314; 67%) had their first recorded self-harm event before their first BDD diagnosis. A total of 17 (0.60%) individuals with BDD and 27 (0.10%) unexposed individuals died by suicide (hazard ratio = 3.47; 95% CI, 1.76-6.85). All results remained robust to additional adjustment for lifetime psychiatric comorbidities. A higher proportion of individuals with BDD who died by suicide had at least 1 previous record of intentional self-harm compared with unexposed individuals (52.94% vs. 22.22%; p = .036). CONCLUSIONS: BDD was associated with a 3-fold increased risk of intentional self-harm and death by suicide.

Body-Focused Repetitive Behavior Disorders in Children and Adolescents: Clinical Characteristics and Treatment Outcomes in a Naturalistic Setting.

Body-focused repetitive behavior disorders, including trichotillomania (hair-pulling disorder) and excoriation (skin picking) disorder, typically emerge in early adolescence, but little is known about the clinical characteristics and treatment outcomes of these disorders in young people, particularly in real-world clinical settings. Participants were 63 children and adolescents (51 girls; age range 9-17) with a diagnosis of trichotillomania (n = 33) and/or skin-picking disorder (n = 33) attending a specialist outpatient clinic in Stockholm, Sweden. Demographic and clinical characteristics were gathered at the initial assessment. Of the 63 assessed youths, 56 received manual-based behavior therapy mainly focusing on habit reversal training, which was combined with medication when deemed appropriate. The mean clinician-reported trichotillomania and skin-picking disorder symptom severity at baseline (n = 63) was in the moderate range. We observed high rates of psychiatric comorbidity (63.5%) and use of psychiatric medication (54.8%). For the 56 individuals undertaking treatment at the clinic, mixed-effects regression models showed a significant decrease in symptom severity from baseline to posttreatment, with gains maintained up to the 12-month follow-up. Substantial and durable improvements were also seen on self-reported symptoms, self-reported depression, and global functioning. Specialist care should be made more widely available to improve the prognosis and quality of life of young people with trichotillomania and skin-picking disorder.

Psychometric evaluation of the appearance anxiety inventory in adolescents with body dysmorphic disorder.

The Appearance Anxiety Inventory (AAI) is a self-report measure assessing the typical cognitions and behaviours of body dysmorphic disorder (BDD). Despite its use in research and clinical settings, its psychometric properties have not been evaluated in young people with BDD. We examined the factor structure, reliability, validity, and sensitivity to change of the AAI in 182 youths with BDD (82.9% girls; Mage = 15.56, SD = 1.37) consecutively referred to two specialist outpatient clinics in Stockholm, Sweden (n = 97) and London, England (n = 85). An exploratory factor analysis identified three factors, namely "threat monitoring", "camouflaging", and "avoidance", explaining 48.15% of the variance. The scale showed good internal consistency (McDonalds omega = 0.83) and adequate convergent validity with the Yale-Brown Obsessive-Compulsive Scale Modified for Body Dysmorphic Disorder for Adolescents (BDD-YBOCS-A; rs = 0.42) and the Clinical Global Impression-Severity Scale (rs = 0.32). Sensitivity to change was adequate, with AAI total scores and individual factor scores significantly decreasing over time in the subgroup of participants receiving multimodal treatment for BDD (n = 79). Change of AAI scores over treatment showed a positive statistically significant moderate-to-good correlation (r = 0.55) with changes in BDD symptom severity, measured by the BDD-YBOCS-A. The study provides empirical support for the use of the AAI in young people with BDD in clinical settings.

All-Cause and Cause-Specific Mortality Among Individuals With Hypochondriasis.

Importance: Hypochondriasis, also known as health anxiety disorder, is a prevalent, yet underdiagnosed psychiatric disorder characterized by persistent preoccupation about having serious and progressive physical disorders. The risk of mortality among individuals with hypochondriasis is unknown. Objective: To investigate all-cause and cause-specific mortality among a large cohort of individuals with hypochondriasis. Design, Setting, and Participants: This Swedish nationwide matched-cohort study included 4129 individuals with a validated International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) diagnosis of hypochondriasis assigned between January 1, 1997, and December 31, 2020, and 41 290 demographically matched individuals without hypochondriasis. Individuals with diagnoses of dysmorphophobia (body dysmorphic disorder) assigned during the same period were excluded from the cohort. Statistical analyses were conducted between May 5 and September 27, 2023. Exposure: Validated ICD-10 diagnoses of hypochondriasis in the National Patient Register. Main Outcome and Measures: All-cause and cause-specific mortality in the Cause of Death Register. Covariates included birth year, sex, county of residence, country of birth (Sweden vs abroad), latest recorded education, civil status, family income, and lifetime psychiatric comorbidities. Stratified Cox proportional hazards regression models were used to estimate the hazard ratios (HRs) and 95% CIs of all-cause and cause-specific mortality. Results: Of the 4129 individuals with hypochondriasis (2342 women [56.7%]; median age at first diagnosis, 34.5 years [IQR, 26.3-46.1 years]) and 41 290 demographically matched individuals without hypochondriasis (23 420 women [56.7%]; median age at matching, 34.5 years [IQR, 26.4-46.2 years]) in the study, 268 individuals with hypochondriasis and 1761 individuals without hypochondriasis died during the study period, corresponding to crude mortality rates of 8.5 and 5.5 per 1000 person-years, respectively. In models adjusted for sociodemographic variables, an increased rate of all-cause mortality was observed among individuals with hypochondriasis compared with individuals without hypochondriasis (HR, 1.69; 95% CI, 1.47-1.93). An increased rate was observed for both natural (HR, 1.60; 95% CI, 1.38-1.85) and unnatural (HR, 2.43; 95% CI, 1.61-3.68) causes of death. Most deaths from unnatural causes were attributed to suicide (HR, 4.14; 95% CI, 2.44-7.03). The results were generally robust to additional adjustment for lifetime psychiatric disorders. Conclusions and Relevance: This cohort study suggests that individuals with hypochondriasis have an increased risk of death from both natural and unnatural causes, particularly suicide, compared with individuals from the general population without hypochondriasis. Improved detection and access to evidence-based care should be prioritized.

Therapist-guided, Internet-delivered cognitive behaviour therapy for adolescents with body dysmorphic disorder: A feasibility trial with long-term follow-up.

Body dysmorphic disorder (BDD) is a prevalent and impairing psychiatric condition that typically debuts in adolescence and is associated with risky behaviours. The disorder can be effectively treated with cognitive behaviour therapy (CBT). However, CBT for BDD is seldom available primarily due to a shortage of trained therapists. Internet-delivered CBT (ICBT) can be a way to increase treatment availability. The aim of this feasibility trial was to evaluate the feasibility, safety, and preliminary efficacy of a CBT protocol for adolescents with BDD, adapted to be delivered over the Internet with minimal therapist support. A total of 20 participants (12-17-year-olds) meeting criteria for BDD were recruited nationally to a specialist outpatient clinic in Stockholm, Sweden. One participant withdrew consent and their data could not be analysed. Nineteen participants were offered 12 modules of therapist-guided ICBT for BDD and were followed up to 12 months post-treatment. Preliminary efficacy was measured at the a priori primary endpoint (3-month follow-up) and at the 12-month follow-up with the clinician-rated Yale-Brown Obsessive Compulsive Scale Modified for BDD for Adolescents. The treatment was rated as both credible and satisfactory and was associated with a large and statistically significant reduction in BDD symptom severity (d = 2.94). The proportion of participants classified as responders at the primary endpoint was 73.7%, and the proportion of full or partial remitters was 63.2%. The average therapist support time was 8 min per participant per week. Treatment gains continued to accrue up to the 12-month follow-up. Two participants attempted suicide and another two reported non-suicidal self-injuries during the study period. ICBT with minimal therapist support is a feasible, potentially efficacious, and durable treatment for adolescents with BDD. Risky behaviours typical of this patient group should be carefully monitored during treatment.

Psychometric Evaluation of the Yale-Brown Obsessive-Compulsive Scale Modified for Body Dysmorphic Disorder for Adolescents (BDD-YBOCS-A).

The Yale-Brown Obsessive-Compulsive Scale Modified for Body Dysmorphic Disorder for Adolescents (BDD-YBOCS-A) is a clinician-rated measure of BDD symptom severity in youth. Despite widespread use in both research and clinical practice, its psychometric properties have not been formally evaluated. The current study examined the factor structure, reliability, validity, and sensitivity to change of the BDD-YBOCS-A in 251 youths with BDD attending two specialist clinics. A principal component analysis identified two factors, explaining 56% of the variance. The scale showed good internal consistency (Cronbach's alpha = 0.87) and adequate convergent and divergent validity. In a subgroup of participants receiving BDD treatment (n = 175), BDD-YBOCS-A scores significantly decreased over time, demonstrating sensitivity to change. BDD-YBOCS-A change scores over treatment were highly correlated with severity changes measured by the Clinical Global Impression - Severity scale (r = .84). The study provides empirical support for the use of the BDD-YBOCS-A in children and adolescents with BDD.

Effectiveness of Multimodal Treatment for Young People With Body Dysmorphic Disorder in Two Specialist Clinics.

Body dysmorphic disorder (BDD) typically originates in adolescence and is associated with considerable adversity. Evidence-based treatments exist but research on clinical outcomes in naturalistic settings is extremely scarce. We evaluated the short- and long-term outcomes of a large cohort of adolescents with BDD receiving specialist multimodal treatment and examined predictors of symptom improvement. We followed 140 young people (age range 10-18) with a diagnosis of BDD treated at two national and specialist outpatient clinics in Stockholm, Sweden (n = 96) and London, England (n = 44), between January 2015 and April 2021. Participants received multimodal treatment consisting of cognitive behavior therapy and, in 72% of cases, medication (primarily selective serotonin reuptake inhibitors). Data were collected at baseline, posttreatment, and 3, 6, and 12 months after treatment.The primary outcome measure was the clinician-rated Yale-Brown Obsessive-Compulsive Scale Modified for BDD, Adolescent version (BDD-YBOCS-A). Secondary outcomes included self-reported measures of BDD symptoms, depressive symptoms, and global functioning. Mixed-effects regression models showed that BDD-YBOCS-A scores decreased significantly from baseline to posttreatment (coefficient [95% confidence interval] = -16.33 [-17.90 to -14.76], p<0.001; within-group effect size (Cohen's d) = 2.08 (95% confidence interval, 1.81 to 2.35). At the end of the treatment, 79% of the participants were classified as responders and 59% as full or partial remitters. BDD symptoms continued to improve throughout the follow-up. Improvement was also seen on all secondary outcome measures. Linear regression models identified baseline BDD symptom severity as a predictor of treatment outcome at posttreatment, but no consistent predictors were found at the 12-month follow-up. To conclude, multimodal treatment for adolescent BDD is effective in both the short- and long-term when provided flexibly within a specialist setting. Considering the high personal and societal costs of BDD, specialist care should be made more widely available.

Clinical characteristics of 172 children and adolescents with body dysmorphic disorder.

Body dysmorphic disorder (BDD) often starts in childhood, with most cases developing symptoms before age 18. Yet, BDD research has primarily focused on adults. We report the clinical characteristics of the world's largest cohort of carefully diagnosed youths with BDD and focus on previously unexplored sex and age differences. We systematically collected clinical data from 172 young people with BDD consecutively referred to 2 specialist pediatric obsessive-compulsive and related disorders outpatient clinics in Stockholm, Sweden and in London, England. A series of clinician-, self-, and parent-reported measures were administered. The cohort consisted of 136 girls, 32 boys, and 4 transgender individuals (age range 10-19 years). The mean severity of BDD symptoms was in the moderate to severe range, with more than one third presenting with severe symptoms and more than half showing poor or absent insight/delusional beliefs. We observed high rates of current psychiatric comorbidity (71.5%), past or current self-harm (52.1%), suicide attempts (11.0%), current desire for cosmetic procedures (53.7%), and complete school dropout (32.4%). Compared to boys, girls had significantly more severe self-reported BDD symptoms, depression, suicidal thoughts, and self-harm. Compared to the younger participants (14 or younger), older participants had significantly more severe compulsions and were more likely to report a desire for conducting cosmetic procedures. Adolescent BDD can be a severe and disabling disorder associated with significant risks and substantial functional impairment. The clinical presentation of the disorder is largely similar across sexes and age groups, indicating the importance of early detection and treatment. More research is needed specifically focusing on boys and pre-pubertal individuals with BDD.

The association between body dysmorphic symptoms and suicidality among adolescents and young adults: a genetically informative study.

BACKGROUND: Previous research indicates that body dysmorphic disorder (BDD) is associated with risk of suicidality. However, studies have relied on small and/or specialist samples and largely focussed on adults, despite these difficulties commonly emerging in youth. Furthermore, the aetiology of the relationship remains unknown. METHODS: Two independent twin samples were identified through the Child and Adolescent Twin Study in Sweden, at ages 18 (N = 6027) and 24 (N = 3454). Participants completed a self-report measure of BDD symptom severity. Young people and parents completed items assessing suicidal ideation/behaviours. Logistic regression models tested the association of suicidality outcomes with: (a) probable BDD, classified using an empirically derived cut-off; and (b) continuous scores of BDD symptoms. Bivariate genetic models examined the aetiology of the association between BDD symptoms and suicidality at both ages. RESULTS: Suicidal ideation and behaviours were common among those with probable BDD at both ages. BDD symptoms, measured continuously, were linked with all aspects of suicidality, and associations generally remained significant after adjusting for depressive and anxiety symptoms. Genetic factors accounted for most of the covariance between BDD symptoms and suicidality (72.9 and 77.7% at ages 18 and 24, respectively), but with significant non-shared environmental influences (27.1 and 22.3% at ages 18 and 24, respectively). CONCLUSIONS: BDD symptoms are associated with a substantial risk of suicidal ideation and behaviours in late adolescence and early adulthood. This relationship is largely explained by common genetic liability, but non-shared environmental effects are also significant and could provide opportunities for prevention among those at high-risk.

Validity and reliability of the diagnostic codes for hypochondriasis and dysmorphophobia in the Swedish National Patient Register: a retrospective chart review.

OBJECTIVES: In the International Classification of Diseases, Tenth Edition (ICD-10), hypochondriasis (illness anxiety disorder) and dysmorphophobia (body dysmorphic disorder) share the same diagnostic code (F45.2). However, the Swedish ICD-10 allows for these disorders to be coded separately (F45.2 and F45.2A, respectively), potentially offering unique opportunities for register-based research on these conditions. We assessed the validity and reliability of their ICD-10 codes in the Swedish National Patient Register (NPR). DESIGN: Retrospective chart review. METHODS: Six hundred individuals with a diagnosis of hypochondriasis or dysmorphophobia (300 each) were randomly selected from the NPR. Their medical files were requested from the corresponding clinics, located anywhere in Sweden. Two independent raters assessed each file according to ICD-10 definitions and Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision and Fifth Edition criteria. Raters also completed the Clinical Global Impression-Severity (CGI-S) and the Global Assessment of Functioning (GAF). PRIMARY OUTCOME MEASURE: Per cent between-rater agreement and positive predictive value (PPV). Intraclass correlation coefficients for the CGI-S and the GAF. RESULTS: Eighty-four hypochondriasis and 122 dysmorphophobia files were received and analysed. The inter-rater agreement rate regarding the presence or absence of a diagnosis was 95.2% for hypochondriasis and 92.6% for dysmorphophobia. Sixty-seven hypochondriasis files (79.8%) and 111 dysmorphophobia files (91.0%) were considered 'true positive' cases (PPV=0.80 and PPV=0.91, respectively). CGI-S scores indicated that symptoms were moderately to markedly severe, while GAF scores suggested moderate impairment for hypochondriasis cases and moderate to serious impairment for dysmorphophobia cases. CGI-S and GAF inter-rater agreement were good for hypochondriasis and moderate for dysmorphophobia. CONCLUSIONS: The Swedish ICD-10 codes for hypochondriasis and dysmorphophobia are sufficiently valid and reliable for register-based studies. The results of such studies should be interpreted in the context of a possible over-representation of severe and highly impaired cases in the register, particularly for dysmorphophobia.

Measuring clinical outcomes in children with pediatric acute-onset neuropsychiatric syndrome: data from a 2-5 year follow-up study.

BACKGROUND: It is unclear how to best measure the complex symptom presentation of pediatric acute-onset neuropsychiatric syndrome (PANS). METHODS: Well-characterized participants of a 2-5 year follow-up study (n = 34; 56% male) underwent clinical evaluations and completed scales assessing global symptom severity, functional impairment and specific psychiatric symptoms. We explored inter-correlations between the measures and used intraclass correlation coefficients to evaluate the agreement between clinician-, parent- and child ratings of the same constructs. RESULTS: Ratings on symptom-specific measures varied largely between participants. Agreement between informants was excellent on functional scales, fair-to-moderate on global severity scales and mixed on symptom-specific scales. Clinician-rated global and functional measures had stronger inter-correlations with parent- and child-rated functional measures than with symptom-specific measures. CONCLUSIONS: General instruments assessing global severity and functioning are well suited for the assessment and follow-up of PANS, but should be complemented by symptom-specific scales representative of core symptoms.

Effectiveness of Behaviour Therapy for Children and Adolescents with Tourette Syndrome and Chronic Tic Disorder in a Naturalistic Setting.

It is unclear if the results of randomised controlled trials (RCTs) of behaviour therapy (BT) for Tourette syndrome (TS) and chronic tic disorder (CTD) can be generalised to naturalistic clinical settings and are durable long-term. In this naturalistic study, 74 young people with TS/CTD received BT at a specialist clinic. Data were collected at baseline, post-treatment, and at 3-, 6-, and 12-month follow-ups. Measures included the Yale Global Tic Severity Scale (YGTSS) and the Clinical Global Impression-Improvement scale (CGI-I), amongst others. Tic severity and tic-related impairment improved after treatment, with large within-group effect sizes. At post-treatment, 57% of the participants were classified as treatment responders according to the CGI-I. Tic severity and tic-related impairment improved further through the follow-up, with 75% treatment responders at the 12-month follow-up. BT is an effective and durable treatment for young people with TS/CTD in a naturalistic specialist clinical setting, with comparable effects to RCTs.

Validity and reliability of social anxiety disorder diagnoses in the Swedish National Patient Register.

BACKGROUND: Population-based administrative registers are often used for research purposes. However, their potential usefulness depends on the validity of the registered information. This study assessed the validity of the recorded codes for social anxiety disorder (SAD), also known as social phobia, in the Swedish National Patient Register (NPR). METHODS: The personal identification numbers of 300 randomly selected individuals with a diagnosis of SAD recorded in the NPR were obtained from the Swedish National Board of Health and Welfare. The medical files of these individuals were then requested from clinics nationally. A total of 117 files were received and two independent raters reviewed each file to assess the presence or absence of SAD, according to the definition of the International Classification of Diseases, Tenth Edition (ICD-10) and the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR). When disagreements between the two raters were found, a third rater reviewed the file to establish a best estimate diagnosis. Positive predictive values (PPV) and agreement between the two initial raters (using Cohen's kappa) were calculated. Additionally, raters completed the Clinical Global Impression - Severity (CGI-S) and the Global Assessment of Functioning (GAF) rating scales for each file. Inter-rater agreement for the CGI-S and the GAF was assessed using intraclass correlation coefficients (ICC). RESULTS: After exclusion of files not containing sufficient information, 95 files were included in the analyses. Of these, 77 files (81.05%) were considered to be 'true positive' cases (PPV = 0.81, 95% confidence interval = 0.72-0.88). Inter-rater agreement regarding the presence or absence of SAD was substantial (κ = 0.72). CGI-S and GAF scores indicated that patients were in the moderate range of severity and functional impairment. Inter-rater agreement for the CGI-S and the GAF was moderate to good (ICC = 0.72 and ICC = 0.82, respectively). CONCLUSIONS: The ICD-10 codes for SAD in the Swedish NPR are generally valid and reliable, but we recommend sensitivity analyses in future register-based studies to minimise the impact of potential diagnostic misclassification. Most patients were moderately severe and impaired, suggesting that results from register-based studies of SAD may be generalizable.

Prevalence and impact of insomnia in children and adolescents with body dysmorphic disorder undergoing multimodal specialist treatment.

Pediatric body dysmorphic disorder (BDD) is challenging to treat. This study aimed to establish the prevalence of insomnia in youth with BDD and explore its impact on clinical outcomes. Sixty-six children and adolescents with BDD consecutively referred to a specialist clinic completed a range of clinical measures, including the Yale-Brown Obsessive-Compulsive Scale Modified for BDD-Adolescent Version (BDD-YBOCS-A), and the Insomnia Severity Index (ISI). Patients with clinical insomnia (ISI score ≥ 9) were compared to the rest of the sample on socio-demographic and clinical features. Fifty-six patients who received multimodal treatment were re-assessed post-treatment. A mixed-model ANOVA was performed to compare treatment outcomes between the insomnia vs. no insomnia groups, and Chi-squared tests were used to compare response and remission rates. According to the ISI, 48% of the sample qualified as having insomnia at baseline. These participants showed significantly higher self-reported BDD symptom severity, more depressive symptoms, and more functional impairment in daily activities. Patients with insomnia improved less on the BDD-YBOCS-A than those without insomnia, although the difference did not reach statistical significance. The rates of responders and remitters were lower in the insomnia group, compared to the non-insomnia group. Insomnia is prevalent in pediatric BDD, and is associated with more severe psychopathology and worse functioning in daily activities. Furthermore, youth experiencing BDD and insomnia may benefit from multimodal treatment to a lesser extent than those without insomnia. If these results are replicated in larger samples, treatment refinements for pediatric BDD could include specific modules to directly target insomnia.

Social skills group training in high-functioning autism: A qualitative responder study.

Systematic reviews show some evidence for the efficacy of group-based social skills group training in children and adolescents with autism spectrum disorder, but more rigorous research is needed to endorse generalizability. In addition, little is known about the perspectives of autistic individuals participating in social skills group training. Using a qualitative approach, the objective of this study was to examine experiences and opinions about social skills group training of children and adolescents with higher functioning autism spectrum disorder and their parents following participation in a manualized social skills group training ("KONTAKT"). Within an ongoing randomized controlled clinical trial (NCT01854346) and based on outcome data from the Social Responsiveness Scale, six high responders and five low-to-non-responders to social skills group training and one parent of each child (N = 22) were deep interviewed. Interestingly, both high responders and low-to-non-responders (and their parents) reported improvements in social communication and related skills (e.g. awareness of own difficulties, self-confidence, independence in everyday life) and overall treatment satisfaction, although more positive intervention experiences were expressed by responders. These findings highlight the added value of collecting verbal data in addition to quantitative data in a comprehensive evaluation of social skills group training.