J Abnorm Child Psychol (2010) 38:1057–1067DOI 10.1007/s10802-010-9425-yBehavioral and Socio-emotional Functioning in Childrenwith Selective Mutism: A Comparison with Anxiousand Typically Developing Children Across MultipleInformantsDiana Carbone & Louis A. Schmidt &Charles C. Cunningham & Angela E. McHolm &Shannon Edison & Jeff St. Pierre & Michael H. BoylePublished online: 23 May 2010# Springer Science+Business Media, LLC 2010Abstract We examined differences among 158 children, 44 implications for clinical practice, whereby social skillswith selective mutism (SM; M=8.2 years, SD=3.4 years), 65 training merits inclusion in intervention for children withwith mixed anxiety (MA; M=8.9 years, SD=3.2 years), and anxiety disorders as well as children with SM.49 community controls (M=7.7 years, SD=2.6 years) onprimary caregiver, teacher, and child reports of behavioral Keywords Selective mutism . Mixed anxiety . Children .and socio-emotional functioning. Children with SM were Social skills . Social anxiety . Parent and teacher reports .rated lower than controls on a range of social skills, but the Internalizing problemsSM and MA groups did not significantly differ on many ofthe social skills and anxiety measures. However, childrenwith SM were rated higher than children with MA and Selective mutism (SM) is a disorder marked by a consistentcontrols on social anxiety. Findings suggest that SM may be failure to speak in certain social situations (e.g., at school)conceptualized as an anxiety disorder, with primary deficits despite the presence of speech in other social situationsin social functioning and social anxiety. This interpretation (e.g., at home; American Psychiatric Association 2000).supports a more specific classification of SM as an anxiety SM is largely considered rare with prevalence ratesdisorder for future diagnostic manuals than is currently estimated to be between 0.03% and 0.2% (Bergman et al.described in the literature. The present findings also have 2002; Brown and Lloyd 1975; Elizur and Perednik 2003; Kolvin and Fundudis 1981; Kopp and Gillberg 1997; Kumpulainen et al. 1998), with higher rates identified inD. Carbone : L. A. Schmidt immigrant populations (Elizur and Perednik 2003). Preva-McMaster Integrative Neuroscience, Discovery, & Study(MiNDS), McMaster University, lence rates for SM are variable in the literature and appearHamilton, ON, Canada to be influenced by the origin of research, diagnostic criteria, age of children, immigrant status, and setting inL. A. Schmidt (*) which SM is sampled (e.g., clinic versus school setting)Department of Psychology, Neuroscience & Behaviour,McMaster University, (Bergman et al. 2002; Kumpulainen 2002; Sharp et al.Hamilton, ON L8S 4K1, Canada 2007). There is little consensus as to the sex ratio of thee-mail: firstname.lastname@example.org disorder, with clinically-referred samples reporting a slightlyC. C. Cunningham : A. E. McHolm : S. Edison : M. H. Boyle higher prevalence of SM in females than males (e.g.,Department of Psychiatry & Behavioural Neurosciences, Cunningham et al. 2004; Dummit et al. 1997; KristensenMcMaster University, 2000). Other studies investigating community- and school-Hamilton, ON, Canada based samples suggest comparable occurrence between the sexes (e.g., Bergman et al. 2002; Elizur and Perednik 2003).J. St. PierreChild and Parent Resource Institute (CPRI), Although SM has a typical onset before the age of five,London, ON, Canada the disorder often does not become evident until school
1058 J Abnorm Child Psychol (2010) 38:1057–1067entry, when expectations (and related pressures) to speak cooperation, than controls. More recently, Cunningham etincrease (Cunningham et al. 2004; Garcia et al. 2004; al. (2006) used the SSRS again and found that bothGiddan et al. 1997). Despite this early onset, children are teachers and parents rated children with SM to be lower onnot commonly referred for clinical assessment until they are verbal and nonverbal social skills than control children, butbetween approximately 6.5 to 9 years of age (Ford et al. the two groups were not different on measures of nonverbal1998; Kumpulainen et al. 1998; Standart and Le Couteur social cooperation.2003). SM may persist for a few months to several years, In addition to the work by Cunningham and colleaguesand adults diagnosed with SM as children often continue to (2004, 2006), a study by Vecchio and Kearney (2005)suffer with social anxiety and deficits in social communi- found that children with SM and children with anxietycation, in addition to displaying other problems with socio- disorders were rated by teachers and parents to have greateremotional and daily adjustment (Remschmidt et al. 2001). internalizing behaviors than controls. Vecchio and KearneyDespite being diagnostically well-documented (Dummit et also found that children with SM and children with anxietyal. 1997; Kopp and Gillberg 1997; Sharp et al. 2007), the disorders did not differ from children in a control group onetiology of SM remains equivocal. externalizing behaviors. Furthermore, children with SM had Currently, SM is ambiguously classified under ‘Other significantly greater total comorbid diagnoses and anxietyDisorders of Infancy, Childhood and Adolescence’ in the disorder diagnoses than children with anxiety disorders,current Diagnostic and Statistical Manual (DSM-IV-TR, based on child, but not parent, report.American Psychiatric Association 2000). This classification There are, in addition, other studies, which have usedis largely disputed as the greater consensus in the literature clinician, parent, and children’s self-report measures toclassifies SM as an anxiety disorder (Anstendig 1999; compare children with SM to children with SP (YeganehSharp et al. 2007; Standart and Le Couteur 2003). The basis et al. 2003, 2006). For example, Yeganeh et al. (2003,for the designation of SM as an anxiety disorder comes 2006) found that children with SM did not report greaterfrom four main findings. First, strong comorbidity with and levels of social anxiety than children with SP, despitecharacteristic similarities between SM and anxiety disor- clinician and observer ratings of greater or equal levels ofders, specifically social phobia (SP), have been identified in social anxiety in the SM and SP groups. Yeganeh andthe literature (e.g., Black and Uhde 1995; Dummit et al. colleagues (2003, 2006) suggested that children with SM1997; Sharp et al. 2007; Vecchio and Kearney 2005). There do not report as large a degree of anxiety, since theiris even the suggestion that SM may be a subtype (Black & inability to talk may serve as a compensatory strategy toUhde, 1992) or developmental precursor (Bergman et al. reduce their anxiety.2002) to SP in some cases. Second, there is evidence Studies that have examined the socio-emotional charac-showing a greater prevalence of anxiety disorders amongst teristics of SM have been limited by several factors,relatives of children with SM than among typically including small sample sizes (e.g., Vecchio and Kearneydeveloping children, which further implicates genetic 2005; Yeganeh et al. 2003, 2006) and a lack of otherfactors in the etiology of the disorder (Black and Uhde clinical group comparisons (e.g., anxious children;1995; Cohan et al. 2006b; Kristensen and Torgerson 2002). Cunningham et al. 2004, 2006). Furthermore, few studiesThird, both SM (Ford et al. 1998) and anxiety disorders have examined social skills in children with SM. Studies(e.g. Hirshfeld-Becker et al. 2007) have been associated that address these issues are needed, given the argumentwith similar temperaments, namely, behavioral inhibition. that 1) SM would be better classified as an anxiety disorderLastly, SM and anxiety disorders both share common (Anstendig 1999; Sharp et al. 2007; Standart and Lepsychotherapeutic and pharmacological treatments (Cohan Couteur 2003), 2) there are conceptual and behavioralet al. 2006a; Standart and Le Couteur 2003). similarities between SM and SP, and 3) the reported Recent research has examined the socio-emotional char- findings of children (e.g., Bernstein et al. 2008) and adultsacteristics of children with SM. For example, Cunningham (e.g., Voncken et al. 2008) with SP suffer from social skillsand colleagues (2004; Cunningham et al. 2006) have deficits.suggested that children with SM exhibit lower social A further limitation concerns the issue that most studiescompetence compared to their typically developed peers. examining SM have largely been informed by parent reportUsing the Social Skills Rating System (SSRS; Gresham and despite the recommendation that a multi-method, multi-Elliot 1990), Cunningham et al. (2004) found that children informant approach be utilized in the assessment of anxietywith SM were rated significantly lower than controls on disorders (Schniering et al. 2000) and SM (Mclnnes andthe parent report of social assertion, social responsibility, Manassis 2005). Given the personal nature of fears, self-social cooperation, and social control subscales. Compar- report is a recommended component of the multi-modalatively, teachers considered children with SM to exhibit battery (Schniering et al. 2000). Teacher ratings of a child’sless social assertion, but not social control or social socio-emotional behavior, in addition to parent and self-
J Abnorm Child Psychol (2010) 38:1057–1067 1059report, are also imperative, since children spend substantial mental health agencies in Southern Ontario andamounts of time in the classroom during their formative children from the McMaster Child Database. Childrenyears (Clarizio 1994). Moreover, there exist anxiety- classified as controls were also obtained from theprovoking situations unique to the school setting about McMaster Child Database only, and all were healthywhich only a teacher may be apt to report. Accordingly, without mental health problems. The McMaster Childteacher assessments are essential for children who typically Database contains the names of children from thedo not speak in the school setting. There is, however, scant community who were recruited at birth from the McMas-research on SM that has included teacher reports. ter University Medical Centre and St. Joseph’s Healthcare, Hamilton, Ontario. Parents consented for their infant’s inclusion in the McMaster Child Database if they wereThe Present Study interested in participating in future research studies. Participant demographics can be found in Table 1.In order to extend the recent work of Cunningham andcolleagues (2004, 2006) and clarify other previous findings, Selective Mutism (SM) Groupwe compared a relatively large sample of children with SMto children with mixed anxiety (MA) disorders and The SM group comprised 44 children (female n=23, maletypically developing children on teacher, primary caregiver, n=21), with a mean age of 8.2 years (SD=3.4 years). Theand child self-report measures of social and emotional children were included in the SM group if their primaryfunctioning. Based on the prior findings by Cunningham caregivers or teachers indicated that the child did not speakand his colleagues (e.g., Cunningham et al. 2004, 2006), we in two or more situations on the Speech Situationspredicted that children with SM would exhibit significantly Questionnaire—Parent Version (SSQ—Parent; or thelower verbal and nonverbal social competence than Speech Situations Questionnaire—Teacher version (SSQ-typically developing children as rated by both primary Teacher; Cunningham et al. 2004, 2006). Classification incaregivers and teachers. Given that SM appears to be the SM group also required that the absence of speakingassociated with internalizing rather than externalizing was not due to a communication disorder, and that thefactors (e.g. Black and Uhde 1995; Dummit et al. 1997; absence of speaking persisted for a minimum of one month.Ford et al. 1998; Kristensen 2000; Steinhausen and Juzi The same criteria used to classify children with SM in the1996; Vecchio and Kearney 2005), we also anticipated that present study have also been used elsewhere (Nowakowskichildren with SM would be significantly higher on et al. 2009).internalizing behaviors and lower on externalizing, hyper- Primary caregiver report on the internalizing section ofactive and problem behaviors than typically developing the Computerized Diagnostic Individual Schedule for Childchildren. Since it may be the case that children with SM do (C-DISC IV; Shaffer et al. 2000) was used to examine thenot report as great a degree of anxiety as indicated by other number of internalizing disorders for which the participantsinformants (Yeganeh et al. 2003, 2006), we expected that met criteria. The C-DISC IV was not used to classifyself-report of social anxiety by children with SM would not children with SM, since its reliability has been establisheddiffer from children with MA and typically developing for anxiety disorders but not for SM. There were sevenchildren, but primary caregivers of children with SM would (15.9%) children classified as SM for which the C-DISC IVindicate higher levels of social anxiety than children with could not be obtained because primary caregivers could notMA and typically developing children. We further hypoth- be reached via telephone to conduct the questionnaire.esized that social skills and anxiety would not be different Twenty-eight of the 37 (63.6%) children classified as SMbetween the SM and MA groups, if SM is conceptualized were diagnosed with one or more anxiety disorders as peras an anxiety disorder. the C-DISC IV. The most common anxiety disorder diagnosis was specific phobia (29.5%), followed by social phobia (18.2%), agoraphobia (15.9%), separation anxietyMethod (13.6%), generalized anxiety disorder (GAD; 2.3%), obsessive-compulsive disorder (OCD; 2.3%), and post-Participants traumatic stress disorder (PTSD; 2.3%).Participants were 158 (81 males, 77 females; M=8.4 years, Mixed Anxiety (MA) GroupSD=3.1 years) children. Children with SM consisted ofreferrals from children’s mental health agencies in The MA group included 65 children (female n=29, maleSouthern Ontario. Children classified as mixed anxiety n=36), with a mean age of 8.9 years (SD=3.2 years). The(MA) were a combination of referrals from children’s children were classified in the MA group if they had one or
1060 J Abnorm Child Psychol (2010) 38:1057–1067Table 1 Demographic Information Selective mutism Mixed anxiety Community control Statistic p-value (n=44) (n=65) (n=49)Percent female 52.3 44.6 51.0 X2(2) = 0.7 0.682Mean (SD) age of child in years 8.2 (3.4) 8.9 (3.2) 7.7 (2.6) F(2,155) = 2.2 0.166Percent in regular classroom 97.7 95.3a 100a X2(4) = 2.9 0.577Age range of primary caregiver <19 (n=1) 19–39 (n=25) 19–39a (n=21) X2(4) = 2.9 0.570 19–39 (n=17) 40–64 (n=40) 40–64 (n=27) 40–64 (n=26)Approximate total income of X2(12) = 35.5 0.0005 household, in prior year, before taxes Less than $15 000 1a 2a 0a $ 15 000–$30 000 3 10 1 $ 30 000–$45 000 6 5 0 $ 45 000–$60 000 0 11 2 $ 60 000–$75 000 12 5 8 $ 75 000–$90 000 11 14 21 Greater than $100 000 10 17 13a indicates group with missing data for that demographic variablemore anxiety disorder diagnoses on the C-DISC IV (social comprehend the questions. A questionnaire package wasphobia, separation anxiety, specific phobia, panic disorder, also sent out to the child’s teacher in which he/she reportedGAD, PTSD, OCD, or agoraphobia), and no diagnosis of on the child’s social skills and problem behaviors.SM as per teacher and primary caregiver report on the The measures collected in the present study were part ofSpeech Situations Questionnaires. Of the 65 children in the a larger study examining the etiology, academic abilities,MA group, 40 (61.5%) had one anxiety disorder, and 25 familial characteristics, and behavioral and psychophysio-(38.5%) had two or more anxiety disorders as per the C- logical correlates of children with SM. Data collection tookDISC IV. The most common anxiety disorder diagnosis place at the Child Emotion Laboratory at McMasteramong the MA group was specific phobia (67.7%), University. All procedures were approved by the McMasterfollowed by social phobia (27.7%), separation anxiety University Health Sciences Research Ethics Board. The(23.1%), GAD (16.9%), OCD (10.8%), panic disorder child received a toy or gift certificate as a token of our(6.2%), and PTSD (1.5%). appreciation at the end of the visit.Community Control Group Primary Caregiver Report MeasuresThe typically developing group comprised 49 children Diagnostic Questionnaires The Speech Situations Ques-(female n=25, male n=24), with a mean age of 7.7 years tionnaire—Parent Version (SSQ-Parent; Cunningham et al.(SD=2.6 years). Children were classified as typically 2004, 2006) assesses a child’s speech patterns in a numberdeveloping if they had no diagnoses as per the CDISC IV, of situations and to several different people as reported byand if they did not meet criteria for SM based on primary the primary caregiver. High internal consistencies of 0.82caregiver and teacher report on the Speech Situations (Cunningham et al. 2006) and 0.92 (Nowakowski et al.Questionnaires. 2009) have been found in prior studies. An internal consistency of 0.92 was found in the present study.Procedure Additionally, primary caregiver report on the internaliz- ing section of the computer assisted Diagnostic InterviewFollowing arrival at the Child Emotion Laboratory, the Schedule for Children (C-DISC IV; Shaffer et al. 2000) wasparent and child were briefed about the procedures and obtained by a trained research assistant via telephonewritten consent was obtained. The primary caregiver then following the initial laboratory visit. The C-DISC IV is afilled out a number of questionnaires. Child self-report of structured diagnostic interview that evaluates the presenceanxiety was also obtained if the child was old enough to of 34 psychiatric disorders in children based on the DSM-
J Abnorm Child Psychol (2010) 38:1057–1067 1061IV (Shaffer et al. 2000). Panic disorder, GAD, social Teacher Report Measuresphobia, specific phobia, separation anxiety, OCD, PTSD,agoraphobia, and major depression are assessed on the Teacher Diagnostic Questionnaires The Speech Situationsinternalizing section of the C-DISC IV. Only the internal- Questionnaire—Teacher Version (SSQ-Teacher; Cunninghamizing section of the C-DISC IV was administered due to et al. 2004, 2006) assesses a child’s speech patterns in atime contraints. number of situations at school and to several different people as reported by the teacher. A high internal consistency of 0.95Social Competence and Problem Behavior Measures was reported recently (Nowakowski et al. 2009) and was 0.95Primary caregivers completed the Social Skills Rating in the present study.System (SSRS)—Parent Version (Gresham and Elliot1990), which is comprised of nine different scales. There Social Competence and Problem Behavior Measuresare four scales that examine social skills: social assertion, Teachers also completed a version of the SSRS that yieldssocial cooperation, social responsibility, and self-control; identical scales to that of the parent version with thethese four sum to a total social skills scale. exception of a social responsibility scale. The SSRS has three scales that pertain to externaliz-ing, internalizing, and hyperactive (only grades K-6) Verbal and Nonverbal Social Interactions We also com-behaviors subscales, which sum to a total problem puted subscales developed by Cunningham et al. (2006) tobehaviors scale. Internal consistency among the scales assess verbal social interactions, nonverbal social interactionsof the SSRS—Parent Version has been reported between and nonverbal classroom cooperation and competence.0.87 and 0.90 (as cited in Cunningham et al. 2004). The Internal consistency among the scales of SSRS—Teacherinternal consistencies for grades K-6 in the present study Version has been reported between 0.93 and 0.94 (as cited inwere between 0.62 and 0.88, and for grades 7–12 were Cunningham et al. 2004). The internal consistencies forbetween 0.74 and 0.91. grades K-6 in the present study were between 0.87 and 0.96, and for grades 7–12 were between 0.72 and 0.93. Cunning-Verbal and Nonverbal Social Skills We also computed three ham et al. (2006) reported internal consistencies of 0.90,scales developed by Cunningham et al. (2006) to assess 0.94 and 0.92 for the verbal social interaction subscale,verbal social skills, nonverbal social skills, and nonverbal nonverbal social interaction subscale, and nonverbal class-cooperation subscales. Cunningham et al. (2006) reported room cooperation and competence subscale, respectively. Ininternal consistencies of 0.78, 0.71, and 0.78 for the verbal the present study, the internal consistencies were: 0.87 forsocial skills, nonverbal social skills, and nonverbal cooper- grades K-6 and 0.80 for grades 7–12 verbal socialation subscales, respectively. For the present study, internal interactions scales, 0.86 for grades K-6 and 0.90 for gradesconsistencies were 0.70 for grades K-6 and 0.58 for grades 7–12 nonverbal social interaction scales, and 0.92 for grades7–12 verbal social skills scales, and 0.83 for grades K-6, K-6 and 0.88 for grades 7–12 nonverbal classroom compe-and 0.76 for grades 7–12 nonverbal social skills scales, and tence scales.were 0.81 for grades K-6, and 0.85 for grades 7–12 for thenonverbal social competence scales. Child Report MeasuresScreen for Child Related Emotional Disorders (SCARED) Although reliability for the SCARED has been tested forThe SCARED (Birmaher et al. 1997) yields five scales children between the ages of 9 to 18 (Birmaher et al. 1997),related to five different anxiety disorders: panic disorder/ we administered the SCARED—Child Version if the childsignificant somatic symptoms, GAD, social anxiety disor- was able to comprehend the questions. The mean age forder, separation anxiety disorder, and significant school children who completed the SCARED—Child Version wasavoidance. We also computed a measure of total anxiety, 9.4 (SD=2.9) years. The SCARED—Child Version haswhich was a sum of all of the questions on the SCARED— identical questions and yields identical scales as theParent Version. The parent version of the SCARED has an SCARED—Parent Version. The child version of theinternal consistency of 0.74 (Birmaher et al. 1997). The SCARED has an internal consistency of 0.93 (Birmaher etinternal consistencies for subscales of the SCARED— al. 1997). We also computed a total score for the SCARED—Parent Version in the present study were between 0.63 Child Version, which was the total sum of all of the questionsand 0.75, and for the total score was 0.92 for children on the SCARED—Child Version. The internal consistenciesbelow age eight. Internal consistencies for subscales of the for subscales of the SCARED—Child Version in the presentSCARED—Parent Version in the present study were study were between 0.56 and 0.82, and for the total score wasbetween 0.76 and 0.93 and for the total score was 0.95 0.86 for children below age eight. Internal consistencies of thefor children eight and above. SCARED—Child Version in the present study were between
1062 J Abnorm Child Psychol (2010) 38:1057–10670.63 and 0.83, and for the total score, it was 0.92 for children using income as a covariate. All post hoc analyses wereeight and above. Bonferroni corrected. The total social skills scale for the SSRS-Parent andMissing Data Teacher Versions and the total anxiety scales for the SCARED Parent and Child Versions were not included in the MAN-Data were missing if specific questions were not completed, COVA analyses as they represent the sum of the subscales inquestions were deemed non-applicable to the child by the each of the questionnaires. The total scales from these scalesprimary caregiver or teacher, certain questions were missed, were analyzed using separate one-way ANCOVAs, withentire questionnaires were not returned to the laboratory, or group (SM, MA, Control) as the between subject-factor andthe child was too young to understand the question(s) in the income as a covariate. All post hoc analyses were Bonferronicase of the SCARED-Child Version. Missing questions for corrected. The total problem behaviors scale was notthe SSRS-Parent and Teacher Version were filled out in analyzed, as it is the sum of three different constructsaccordance with the protocol outlined in Gresham and (internalizing, externalizing and hyperactive behaviors) thatElliot (1990). Missing questions for the SCARED-Parent should be analyzed and reported separately.and Child Versions were filled in by computing the average To assess whether primary caregiver and child report ofof the questions pertaining to a specific scale that the anxiety differed within the SM and MA groups, paired-samplesmissing question was relevant to and then recalculating the t-tests were conducted using the SCARED—Parent and Childscale. Importantly, the groups did not significantly differ on Versions total anxiety score and social anxiety score.the amount of missing data. There were a total of sevenparticipants missing the SSRS—Parent Version, 25 partic-ipants missing the SSRS—Teacher Version, eight partic- Resultsipants missing the SCARED—Child Version, and fiveparticipants missing the SCARED—Parent Version. Of the SSRS-Parent Version: Social Competenceremaining participants, there were 1.1% data missing fromthe SSRS—Parent Version, 0.6% data missing from the Consistent with our predictions, the MANCOVA for theSSRS—Teacher Version, 0.09% data missing from the social skills subscales indicated a significant multivariateSCARED—Parent Version, and 0.06% data missing from main effect of group (Wilks’Λ, F(8,256) = 6.886, p=0.0005)the SCARED—Child Version. that further indicated a significant main effect of group on the social assertion, social responsibility, and self-control,Data Analyses but not the social cooperation subscales (see Table 2). A one-way ANCOVA also indicated that there was aIncome in the prior year before taxes differed significantly significant main effect of group on the total social skills scaleamong the three groups (X2(12) = 35.5, p<0.05) and was (F(2,131) = 12.3, p=0.0005; see Table 2).significantly correlated with all of the measures in the study Follow-up tests confirmed that the SM and MA groupsexcept for the SSRS—Teacher Version social assertion and had significantly lower social assertion (p<0.006) and totalverbal social skills scales, the SCARED—Child Version, social skills (all p’s<0.02) than the control group. Primaryand the SCARED—Parent Version social anxiety and caregivers also rated the SM group lower in socialschool avoidance scales. Accordingly, income was consid- responsibility skills than the MA and control groups (allered as a covariate in all analyses. p’s<0.006). There were no significant group differences on To examine differences among the three groups on the the self-control scale following Bonferroni correction.various behavioral and socio-emotional functioning mea-sures completed by the primary caregiver, teacher, and SSRS-Parent Version: Verbal and Nonverbal Social Skillschildren, separate one-way multivariate analyses of covari-ance (MANCOVA) tests were conducted, with group (SM, The MANCOVA for the verbal social skills scale, nonver-MA, Control) as the between-subject factor and the bal social skills scale, and nonverbal cooperation scalesubscales (e.g., SSRS-Parent subscales: social cooperation, revealed a main effect of group (Wilks’Λ, F(6, 260) =social assertion, social responsibility, self-control) as the 11.679, p=0.0005) for all of the subscales (see Table 2).dependent variables. A similar MANCOVA was performed The SM group had significantly lower verbal social skillswith group (SM, MA, Control) as the between-subject than the MA and control groups (p’s<0.006; see Table 2factor and the subscales (internalizing, externalizing, and and Fig. 2). Furthermore, the SM and MA groups hadhyperactive behaviors) as the dependent measures. Signif- significantly lower nonverbal social skills than the controlicant main effects were followed up with analyses of group (p’s<0.006). There were no other significant groupcovariance (ANCOVA) tests on the dependent variables differences following Bonferroni correction.
J Abnorm Child Psychol (2010) 38:1057–1067 1063Table 2 Group Differences on Social Skills Rating System (SSRS) and Verbal and Nonverbal Social Behavior Measures as Completed byPrimary CaregiversMeasure Selective mutism Mixed anxiety Controls f-ratio p Mean SD Mean SD Mean SDSocial competence measures Social cooperation 11.4 (3.6) 10.6 (3.8) 12.4 (3.0) 1.8 0.175 Social assertion 11.0b (3.5) 12.5a (3.9) 16.1a,b (3.3) 17.8 0.0005 Social responsibility 9.9c,d (3.7) 11.8c (2.9) 13.6d (2.9) 13.5 0.0005 Self-control 11.9 (2.8) 10.9 (3.9) 13.5 (3.8) 3.5 0.034 Total social skills 44.2e (9.1) 45.9f (10.0) 48.3e,f (11.0) 12.3 0.0005Problem behavior measures Externalizing behaviors 3.7 (2.1) 4.8 (2.9) 3.4 (2.4) 2.0 0.139 Internalizing behaviors 5.6g (2.2) 5.9h (3.1) 2.9g,h (2.4) 11.2 0.0005 Hyperactive behaviors 3.6 (2.5) 5.3 (2.8) 4.1 (2.7) 3.0 0.054Verbal and nonverbal behavior measures Verbal social skills 10.8i,j (3.2) 13.8i (3.8) 16.1j (4.0) 22.8 0.0005 Nonverbal social skills 15.4k (4.2) 15.7l (4.1) 20.2k,l (4.8) 12.5 0.0005 Nonverbal social cooperation 15.8 (3.5) 13.6 (4.0) 16.3 (4.5) 3.7 0.028Identical superscripts indicate statistical significance between those groupsSSRS-Parent Version: Problem Behaviors SM group had lower verbal social skills than the MA and control groups (p<0.006; see Table 3 and Fig. 2). The SMThe MANCOVA indicated a significant main effect for group was also lower in nonverbal social skills than thegroup on the problem behavior subscales (Wilks’Λ, F(6, control group (p<0.006), and the MA group had lower202) = 5.088, p=0.002), but only for the internalizingsubscale (see Table 2 and Fig. 1). Follow up analysessupported our hypothesis that the SM and MA groupshad significantly higher internalizing behaviors than thecontrol group (p<0.02), but they did not differ from eachother.SSRS-Teacher Version: Social CompetenceThe MANCOVA indicated a significant multivariate maineffect for group on the social skills subscales (Wilks’Λ, F(6,194) = 9.713, p=0.0005; see Table 3). A one-way ANCOVAalso revealed a significant main effect for group on the totalsocial skills scale (F(2, 99) = 9.126, p=0.001). Follow-uptests indicated that the SM and MA groups had significantlylower self-control (p’s<0.006) and total social skills than thecontrol group (p’s<0.02). Teachers also rated children withSM lower in social assertion skills than the MA and controlgroup (p’s<0.006). Additionally, children with MA wereconsidered to be lower in social cooperation skills than thecontrol group (p<0.006).SSRS-Teacher Version: Verbal and Nonverbal Social Skills Note: ** p < .02 for SSRS-Parent Version ** p < .006 for SSRS-Teacher VersionThe MANCOVA revealed a significant main effect of group Fig. 1 Primary caregiver and teacher report of internalizing behaviors(Wilks’Λ, F(6,196) = 12.406, p=0.0005) on all of the on the Social Skills Rating System (SSRS). Note: Internalizingsubscales (see Table 3). Follow-up tests showed that the behaviors were z-scored to standardize comparison across informants
1064 J Abnorm Child Psychol (2010) 38:1057–1067Table 3 Group Differences on Social Skills Rating System (SSRS) and Verbal and Nonverbal Social Behavior Measures as Completed byTeachersMeasure Selective mutism Mixed anxiety Controls f-ratio p Mean SD Mean SD Mean SDSocial competence measures Social cooperation 14.5 (4.0) 12.9a (5.5) 16.6a (3.8) 4.8 0.010 Social assertion 5.0b,c (3.6) 10.3b (4.7) 11.9c (4.8) 22.5 0.0005 Self-control 12.6d (4.0) 12.7e (5.0) 16.3d,e (2.2) 5.8 0.004 Total social skills 32.0f (8.8) 35.8g (13.1) 44.7f,g (6.1) 9.1 0.0005Problem behavior measures Externalizing behaviors 0.5h (1.2) 2.9h,i (3.6) 0.6i (1.3) 8.0 0.001 Internalizing behaviors 6.6k (3.2) 4.9j (3.1) 1.7j,k (1.8) 17.5 0.0005 Hyperactive behaviors 2.2 (2.3) 4.3 (4.0) 1.8 (2.4) 5.2 0.007Verbal and nonverbal behavior measures Verbal social skills 2.0l,m (2.4) 6.9l (3.1) 7.8m (2.2) 33.6 0.0005 Nonverbal classroom cooperation and competence 18.1 (4.9) 16.n (7.1) 21.2n (4.2) 7.0 0.001 Nonverbal social interactions 10.9o (4.8) 12.7 (4.6) 15.7o (2.4) 5.5 0.005Identical superscripts indicate statistical significance between those groupsclassroom cooperation and competence skills compared to (Wilks’Λ, F(6,170) = 8.774, p=0.0005; see Table 3). In linethe control group (p<0.006). with our predictions, the SM and MA groups had significantly higher internalizing behavior scores than theSSRS-Teacher Version: Problem Behaviors control group (p <.006; see Table 3 and Fig. 1). The SM and control groups had significantly lower externalizingThe MANCOVA revealed a significant multivariate main behaviors than the MA group (p’s<0.006). There were noeffect for group on all of the problem behavior subscales other group differences following Bonferroni correction.Note: ** p < .006 Note: ** p < .003Fig. 2 Primary caregiver and teacher report of verbal social skills onthe Social Skills Rating System (SSRS). Note: Verbal social skills Fig. 3 Primary caregiver report of social anxiety on the Screen forwere z-scored to standardize comparison across informants Child Related Emotional Disorders (SCARED)
J Abnorm Child Psychol (2010) 38:1057–1067 1065SCARED—Parent Version Our findings support and extend recent research (e.g., Cunningham et al. 2004, 2006; Vecchio and KearneyAnxiety Subscales The MANCOVA revealed a significant 2005), suggesting that children with SM appear lessmultivariate main effect for group (F(10, 284) = 12.5, p= socially competent and more prone to internalizing behav-0.0005) on all of the subscales (see Table 4). A one-way iors compared to controls as reported by primary caregiversANCOVA also showed a significant main effect for group and teachers. More specifically, children with SM wereon the total anxiety score (F(2, 146) = 28.4, p=0.0005). rated significantly lower than controls on teacher-reportedWhile the SM and MA groups had significantly higher social assertion, self-control and total social skills and onGAD, separation anxiety, and school avoidance scores (all primary caregiver reported social responsibility and totalp’s<0.003) as well as higher total anxiety (p<0.02) than the social skills. Furthermore, consistent with findings bycontrol group, the two groups did differ from each other on Cunningham et al. (2006), children with SM were ratedlevels of social anxiety and panic/somatic symptoms. More by both primary caregivers and teachers lower on verbalspecifically, the SM group had higher social anxiety scores social skills compared to both the MA and control groups.than the MA group and the control group and the MA Consistent with our predictions, we also found that primarygroup had higher social anxiety scores than the control caregivers indicated greater social anxiety levels in childrengroup (see Fig. 3). The MA group also had higher panic/ with SM than the children reported for themselves, which issomatic symptoms compared to the SM and control groups supportive of the idea that children with SM may use their(all p’s<0.003). mutism as a compensatory strategy to reduce their anxiety (Yeganeh et al. 2003, 2006).SCARED—Child Version As expected, given the general agreement in the literature that SM should be better classified as an anxiety disorder (e.g.There were no significant group differences. Anstendig 1999; Sharp et al. 2007; Standart and Le Couteur 2003), children with SM, and children with MA, did notSCARED—Parent and Child Comparisons significantly differ on many of the social skills and anxiety measures regardless of informant. For example, the SM andA paired-samples t-test on the social anxiety subscale of the MA groups did not significantly differ on internalizingSCARED indicated significantly greater report of child behaviors, social cooperation, self-control, total social skills,social anxiety by primary caregivers (M=11.7, SD=2.7) and on teacher reported nonverbal social skills, and class-than self-report of social anxiety by the children (M=7.7, room cooperation and competence. The SM and MA groupsSD=3.5) (t(35) = 6.1, p<0.01). additionally did not differ on primary caregiver reported internalizing behaviors, social assertion, self-control, nonver-Discussion bal social skills and total social skills. Also in line with our predictions, children with SM and anxiety disorders were notThe goal of the present study was to examine group significantly different on behaviors reflecting GAD, separa-differences among children with SM, mixed anxiety, and tion anxiety, school avoidance, and overall anxiety, althoughcontrols on measures of behavioral and socio-emotional primary caregivers rated the SM group significantly higher infunctioning. We used a relatively large sample size, multi- behaviors reflecting social anxiety than the MA andinformant report (i.e. primary caregiver, teacher, and child control groups. Taken together, these results suggest thatself-report) and included an anxious comparison group. deficits in social abilities are evident in both children withTable 4 Group Differences on the Screen for Child Anxiety Related Emotional Disorders (SCARED) as Completed by Primary CaregiversMeasure Selective mutism Mixed anxiety Controls f-ratio p Mean SD Mean SD Mean SDPanic/significant somatic symptoms 3.1a (2.9) 7.7a,b (4.6) 3.7b (3.0) 11.3 0.0005Generalized anxiety disorder 6.6c (4.9) 8.7d (5.5) 2.6c,d (3.2) 18.1 0.0005Separation anxiety disorder 5.7e (3.6) 6.5f (4.3) 2.6e,f (3.1) 11.5 0.0005Social anxiety disorder 11.7g,h (2.7) 7.7g,i (4.6) 3.7h,i (3.0) 47.6 0.0005School avoidance 1.9j (2.0) 2.4k (2.0) 0.5j,k (1.0) 13.9 0.0005Total anxiety 28.9l (11.4) 30.2m (16.2) 10.6l,m (9.3) 28.4 0.0005Identical superscripts indicate statistical significance between those groups
1066 J Abnorm Child Psychol (2010) 38:1057–1067SM and children with anxiety disorders. Furthermore, the Chair in Patient-Centred Health Care. The authors would like to thank Lindsay Bennett, Sue McKee, Renee Nossal, Matilda Nowakowski,findings suggest that SM may be considered an anxiety and Jamie Sawyer for their assistance with data collection. We woulddisorder characterized by social anxiety. More detailed also like to thank the many children, their primary caregivers andobservational analyses of the types of social inhibitions teachers for their participation in the study.experienced by children and youth with social phobia butwho speak at school versus those with SM and SP versus Referencesthose with SM but less social inhibition is warranted. Thisapproach would also aid in the understanding of the role American Psychiatric Association. (2000). Diagnostic and statisticalof oral speech in social skill development in children and manual of mental disorders DSM-IV-TR. Washington: Author.may help to refine the classification of SM. Anstendig, K. D. (1999). Is selective mutism an anxiety disorder? Rethinking its DSM-IV classification. Journal of Anxiety Disorders, 13, 417–434.Limitations Bergman, R. L., Piacentini, J., & McCracken, J. T. (2002). Prevalence and description of selective mutism in a school-based sample.There were at least three limitations of the present study. Journal of the American Academy of Child and Adolescent Psychiatry, 41, 938–946.First, although there was no systematic loss of data among Bernstein, G. A., Bernat, D. H., Davis, A. A., & Layne, A. E. (2008).the three groups, several questionnaire packages from the Symptom presentation and classroom functioning in a nonclinicalchild’s teacher were not returned, which reduced the sample sample of children with social phobia. Depression and Anxiety,size for the teacher analyses and perhaps reliability. Second, 25, 752–760. Birmaher, B., Khetarpal, S., Brent, D., Cully, M., Balach, L.,the mean substitution method for filling in missing data for Kaufman, J., et al. (1997). The screen for child anxiety relatedsome of our measures has been criticized by some (e.g., emotional disorders (SCARED): Scale construction and psycho-Enders 2006). However, given the small percentage of metric characteristics. Journal of the American Academy of Childmissing data in this sample the mean substitution method is and Adolescent Psychiatry, 36, 545–553. Black, B., & Uhde, T. W. (1992). Elective mutism as a variant ofnot likely to have impacted results in a meaningful way. social phobia. Journal of the American Academy of Child andThird, some research (e.g., Comer and Kendall 2004) Adolescent Psychiatry, 31, 1090–1094.suggests that parental psychopathology (e.g. anxiety) may Black, B., & Uhde, T. W. (1995). Psychiatric characteristics of childreninfluence parental ratings of their child’s psychopathology. with selective mutism: A pilot study. Journal of the American Academy of Child & Adolescent Psychiatry, 34, 847–856.We were, however, not able to examine whether any of the Brown, J., & Llyod, H. (1975). A controlled study of not speaking inparents met clinical diagnosis for psychopathology. school. Journal of the Association of Workers for Maladjusted Children, 3, 49–63.Conclusion and Implications Clarizio, H. (1994). Assessment of depression in children and adolescents by parents, teachers and peers. In W. Reynolds & H. Johnston (Eds.), Handbook of depression in children andWe found that children with selective mutism were rated to adolescents (pp. 235–248). New York: Plenum Press.have less social competence than controls by both primary Cohan, S. L., Chavira, D. A., & Stein, M. B. (2006). Practitionercaregivers and teachers. SM children, however, were not review: Psychosocial interventions for children with selective mutism: A critical evaluation of the literature from 1990–2005.rated significantly different on a number of social skills and Journal of Child Psychology and Psychiatry, 47, 1085–1097.anxiety measures than children with anxiety disorders. Cohan, S. L., Price, J. M., & Stein, M. B. (2006). Suffering in silence:Importantly, children with SM were rated higher in levels of Why a developmental psychopathology perspective on selectivesocial anxiety compared to their anxious and typically mutism is needed. Journal of Developmental and Behavioral Pediatrics, 27, 341–355.developing counterparts. Based upon the present findings, it Comer, J. S., & Kendall, P. C. (2004). A symptom-level examinationis plausible that SM may be conceptualized as an anxiety of parent-child agreement in the diagnosis of anxious youths.disorder with a primary deficit in social functioning. This Journal of the American Academy of Child and Adolescentsuggestion further impacts the formation of future diagnos- Psychiatry, 43, 878–886. Cunningham, C. E., McHolm, A. E., & Boyle, M. H. (2006). Socialtic manuals: It may be more appropriate to classify SM as phobia, anxiety, oppositional behavior, social skills, and self-an anxiety disorder, and more specifically a social anxiety concept in children with specific selective mutism, generalizeddisorder, than the currently ambiguous classification of SM selective mutism, and community controls. European Child &in ‘Other Disorders of Infancy, Childhood, and Adoles- Adolescent Psychiatry, 15, 245–255. Cunningham, C. E., McHolm, A., Boyle, M. H., & Patel, S. (2004).cence’. Furthermore, the present findings have implications Behavioral and emotional adjustment, family functioning, aca-for clinical practice, whereby social skills training merits demic performance, and social relationships in children withinclusion in intervention for children with anxiety disorders selective mutism. Journal of Child Psychology and Psychiatry,as well as children with SM. 45, 1363–1372. Dummit, E. S., Klein, R. G., Tancer, N. K., & Asche, B. (1997). Systematic assessment of 50 children with selective mutism.Acknowledgements This research was supported by a grant from Journal of the American Academy of Child and Adolescentthe Ontario Mental Health Foundation (OMHF) and the Jack Laidlaw Psychiatry, 36, 653–660.
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