Anxiety is a complex psychological construct composed

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1 AJSLP Review Anxiety and Stuttering: Continuing to Explore a Complex Relationship Lisa Iverach, a Ross G. Menzies, a Sue O'Brian, a Ann Packman, a and Mark Onslow a Purpose: The relationship between anxiety and stuttering has been widely studied. However, a review conducted more than 10 years ago (Menzies, Onslow, & Packman, 1999) identified 5 methodological issues thought to preclude consistent research findings regarding the nature of this relationship. The purpose of the present review was to determine whether methodological improvements have occurred since the Menzies et al. (1999) review. Method: Literature published since the Menzies et al. review was evaluated with regard to the 5 methodological issues identified in that review: (a) the construct of anxiety, (b) trait anxiety measures, (c) participant numbers, (d) treatment status of participants, and (e) speaking tasks. Results: Despite some remaining ambiguous findings, research published since the Menzies et al. review has provided far stronger evidence of a relationship between stuttering and anxiety, and has focused more on social anxiety, expectancies of social harm, and fear of negative evaluation. Conclusion: The aims of future research should be to improve research design, increase statistical power, employ multidimensional measures of anxiety, and further develop anxiolytic treatment options for people who stutter. Key Words: stuttering, anxiety, review, social phobia, fear of negative evaluation Anxiety is a complex psychological construct composed of verbal-cognitive, behavioral, and physiological components (Ezrati-Vinacour & Levin, 2004; Menzies, Onslow, & Packman, 1999). It is also considered to include both transient (state) aspects and more generalized and stable (trait) characteristics (Menzies et al., 1999; Spielberger, Gorsuch, Lushene, Vagg, & Jacobs, 1983). The experience of anxiety can include thoughts and expectancies of negative events, escape or avoidance of feared situations, and physical sensations such as muscle tension and heart palpitations (Kraaimaat, Vanryckeghem, & Van Dam- Baggen, 2002; Menzies et al., 1999). Numerous measures have been developed to evaluate anxiety, including unidimensional measures that assess anxiety as a single or global construct, such as the State-Trait Anxiety Inventory (Spielberger et al., 1983), and multidimensional measures that regard anxiety as composed of numerous components, such as the Endler Multidimensional Anxiety Scales (Endler, Edwards, & Vitelli, 1991). a Australian Stuttering Research Centre, The University of Sydney, Australia Correspondence to Mark Onslow: mark.onslow@sydney.edu.au Editor: Laura Justice Associate Editor: Patrick Finn Received October 28, 2010 Revision received February 23, 2011 Accepted March 17, 2011 DOI: / (2011/ ) Anxiety and Stuttering Anxiety is one of the most frequently observed and widely studied psychological concomitants of stuttering (Ingham, 1984; Peters & Hulstijn, 1984). There are a number of reasons this association between anxiety and stuttering has been so widespread. In particular, speech is fundamental to daily functioning and to the development and maintenance of social networks and relationships (Messenger, Onslow, Packman, & Menzies, 2004). However, many people who stutter face considerable difficulties when trying to speak (Packman, Menzies, & Onslow, 2000). Added to this, stuttering is associated with negative consequences that can adversely affect social and emotional functioning, relationships, quality of life, and mental health (Craig, Blumgart, & Tran, 2009). In fact, the negative consequences of stuttering can begin shortly after onset during the preschool years (Ezrati-Vinacour, Platzky, & Yairi, 2001; Langevin, Packman, & Onslow, 2009) and can continue across the lifespan to include negative listener reactions and stereotypes, bullying and teasing, social isolation and rejection, relationship difficulties, educational and occupational underachievement, expectancies of social harm, and fear of speaking in social situations (Blood & Blood, 2007; Cream, Onslow, Packman, & Llewellyn, 2003; Davis, Howell, & Cooke, 2002; O Brian, Jones, Packman, Menzies, & Onslow, 2011; Turnbaugh, Guitar, & Hoffman, 1979). As a result, anxiety in speaking-related or social situations can be considered a predictable outcome of the negative communication consequences experienced across the lifespan for people who stutter (Bloodstein, 1995; Ingham, 1984; American Journal of Speech-Language Pathology Vol August 2011 A American Speech-Language-Hearing Association 221

2 Miller & Watson, 1992). Therefore, understanding the nature of the relationship between anxiety and stuttering is an important issue (Kraaimaat et al., 2002). However, the nature of this relationship and the mechanisms underlying it have previously been poorly understood, and past scientific evidence has been regarded as ambiguous and difficult to interpret (Andrews et al., 1983; Attanasio, 2000; Blood, Blood, Bennett, Simpson, & Susman, 1994; Craig, Hancock, Tran, & Craig, 2003; Ezrati-Vinacour & Levin, 2004; Ingham, 1984; Kraaimaat et al., 2002; Menzies et al., 1999). The inconsistent nature of research findings regarding anxiety and stuttering has been discussed in past reports (Craig & Tran, 2006; Ingham, 1984; Menzies et al., 1999). Ingham s (1984) Review In 1984, Ingham made a significant contribution to the field by reviewing the principle theoretical models underpinning associations between anxiety and stuttering. In particular, Ingham reviewed the influence of psychological theories on the development of stuttering treatments and evaluated anxiety-modification techniques used to treat stuttering. Ingham also reviewed research regarding the physiological factors associated with anxiety and stuttering, including the experience of physical tension during moments of stuttering. He argued that conclusive evidence of such a relationship was not apparent in his review of the research literature at the time. In particular, Ingham suggested that research evidence regarding the causal effect of physiological tension associated with stuttering was unclear, and that physiological evidence of anxiety could not necessarily be taken to indicate the actual presence of anxiety. In addition, Ingham argued that the theoretical foundations underpinning some anxiety-reduction approaches to stuttering were questionable and lacking in objective speech data. Ingham (1984) highlighted a number of methodological flaws in the stuttering literature that were thought to explain why a clear and systematic relationship between anxiety and stuttering had not become apparent. According to Ingham, these inadequacies included the use of anecdotal reporting, the lack of independent measures of state anxiety, and failure of anxiety treatments to result in stuttering reductions. Ingham also suggested that a linear relationship between stuttering and anxiety should not be assumed for all people who stutter, and that state anxiety might have a facilitative rather than debilitating effect on stuttering in some cases. Overall, Ingham concluded that the overall tenor of the findings from the studies reviewed is that there is little evidence of a clinically significant, or even theoretically palpable, relationship between stuttering and anxiety (p. 132). Menzies et al. s (1999) Review Fifteen years after Ingham s (1984) review of what he considered to be relatively unprofitable research (p. 133), Menzies et al. (1999) conducted a review of the literature to further explore the complex and often poorly understood relationship between anxiety and stuttering. In their review, Menzies et al. identified five core methodological issues in the literature thought to preclude clear and consistent research findings regarding the nature of anxiety and stuttering. These methodological issues included use of (a) physiological measures of anxiety, rather than self-report or behavioral measures of anxiety (such as situation avoidance), fear of negative evaluation, and expectancy of social harm; (b) unidimensional measures of trait anxiety rather than multidimensional measures designed specifically to evaluate social anxiety; (c) small sample sizes with insufficient power to detect significant differences; (d) participants who had received treatment for stuttering in the past or who were seeking or currently undergoing speech treatment rather than participants who had never received treatment; and (e) single speaking tasks in order to elicit or manipulate anxiety in people who stutter rather than multiple or individualized behavioral tasks. A number of these methodological issues have been highlighted by other researchers (e.g., Craig, 1990). Menzies et al. (1999) concluded that the relationship between anxiety and stuttering could not be fully understood until the above methodological limitations had been overcome. In a similar manner to Ingham (1984), they also argued that the inadequate literature on anxiety and stuttering is not just an academic problem. On the contrary, an ambiguous literature on the role that anxiety plays in the condition impairs clinical practice and retards the development of novel clinical procedures. Until the precise nature of the relationship between anxiety and stuttering is understood, fully appropriate treatment of adult stuttering cannot be offered. (p. 8) Hence, Menzies et al. highlighted the need for improvements in research design in stuttering research, including the use of larger sample sizes to increase statistical power, and the application of multidimensional measures of anxiety (Blomgren, Roy, Callister, & Merrill, 2005; Craig et al., 2003; Ezrati-Vinacour & Levin, 2004; Menzies et al., 1999). They also underscored the need to provide anxiolytic treatments for people who stutter and who report anxiety. The Present Review Although the Menzies et al. (1999) review shed necessary light on the long and tangled relationship between anxiety and stuttering (Attanasio, 2000, p. 89), over a decade has passed since its publication. Therefore, it is timely to investigate whether any changes in research design or methodological improvements have occurred since publication of the Menzies et al. review. As a result, the purpose of the present review is to (a) determine whether the five methodological issues identified by Menzies et al. are still relevant to research published since their review, (b) establish whether research evidence regarding the relationship between anxiety and stuttering has become less ambiguous and more conclusive since the Menzies et al. review, (c) identify any further methodological issues apparent in the research regarding anxiety and stuttering, and (d) determine whether any methodological improvements in anxiety research since the Menzies et al. review have resulted in changes to clinical practice and the treatment of anxiety in stuttering. 222 American Journal of Speech-Language Pathology Vol August 2011

3 Methodological Issues The Construct of Anxiety The first methodological issue highlighted by Menzies et al. (1999) relates to the construct of anxiety. In particular, Menzies et al. argued that much of the research at the time of their review had not taken into account the multidimensional nature of anxiety. Instead, a sizable proportion of research had focused on the physiological component of anxiety, which Menzies et al. argued was possibly the least useful indicator of social anxiety. Not only are the results of physiological measures of social anxiety thought to vary across individuals, thereby making it difficult to interpret the findings of such evaluations, but they are also poorly correlated with the verbal-cognitive and behavioral components of anxiety (Menzies et al.). Ingham (1984) also suggested that physiological evidence of anxiety is not necessarily evidence that the subject actually experiences anxiety (p. 129). Therefore, Menzies et al. argued that the use of physiological measures of anxiety reduces the likelihood of clearly identifying anxiety, whereas self-report and behavioral measures may provide more sound indications of anxiety, at least with research about social anxiety and stuttering. In addition, Menzies et al. (1999) suggested that evaluation of expectancies of social harm, fear of negative evaluation, and anticipation of stuttering is also of particular importance when evaluating the relationship between anxiety and stuttering (Ginsberg, 2000; Ingham, 1984; Menzies et al., 1999). Fear of negative evaluation and expectancies of harm are central constructs in the experience and assessment of anxiety (Messenger et al., 2004). Adults who stutter tend to fear speaking situations (Mahr & Torosian, 1999), and negative social evaluation is thought to be one of the most likely mediators of speech-related anxiety for adults who stutter (Menzies et al., 1999). However, at the time of the Menzies et al. review, only a single study (Poulton & Andrews, 1994) was identified that evaluated social expectancy and subjective anxiety during a speaking task. Therefore, Menzies et al. recommended the incorporation of self-report and behavioral measures of anxiety into future research, including measures of expectancies of social harm and negative evaluation. Since the Menzies et al. (1999) review, a small number of studies have continued to explore the physiological component of anxiety. For instance, Dietrich and Roaman (2001) investigated the relationship between perceptions of speechrelated anxiety and physiological arousal in specific speaking situations in a sample of 24 adults who stuttered. They found no correlations between participants predictions of speech-related anxiety in 20 hypothetical speaking situations and actual skin conduction responses during enactment of four speaking situations. In addition, Alm (2004) reviewed findings regarding the propensity for adults who stutter to demonstrate reductions in heart rate in stressful speaking situations (e.g., Peters & Hulstijn, 1984; Weber & Smith, 1990). Alm suggested that parasympathetic suppression of heart rate might be caused by speech-related anticipatory anxiety in people who stutter and argued that anticipatory anxiety in speaking situations might be a conditioned response to previous stuttering experiences. A more substantial number of studies have investigated the socially evaluative aspects of anxiety in stuttering, including use of self-report measures of anxiety and fear of negative evaluation such as the Endler Multidimensional Anxiety Scales-Trait (EMAS-T; Endler et al., 1991) and the Fear of Negative Evaluation Scale (FNE; Watson & Friend, 1969). Findings from these studies have highlighted the propensity for people who stutter to experience anticipatory anxiety and fear of being penalized by listeners (Cream et al., 2003; Plexico, Manning, & Levitt, 2009). Messenger and colleagues (2004), in particular, explored the relationship between stuttering, social anxiety, and negative social expectancies. They found that scores on the FNE and the Social Evaluation and New/Strange Situations subtests of the EMAS-T were significantly higher for a sample of 34 adults who stuttered than for 34 controls. These findings, which confirmed the socially evaluative nature of anxiety in stuttering, have also been supported by further research. For instance, Blumgart, Tran, and Craig (2010) reported that the mean FNE score for a large sample of 200 adults who stuttered was significantly higher than the mean score for 200 controls. Similarly, Iverach, O Brian, et al. (2009) administered a number of anxiety-related selfreport measures, including the FNE and the EMAS-T, to a large sample of 92 stuttering adults. Results revealed that the adults who stuttered were characterized by increased fear of negative evaluation and anxiety in socially evaluative or new/strange situations when compared with matched controls. However, these anxiety levels were not as high as those reported for clinically anxious or socially phobic samples. Mahr and Torosian (1999) also reported that adults who stutter may have increased levels of social anxiety and avoidance compared to nonstuttering controls, but that they may not experience fear of negative evaluation to the same degree as individuals with social phobia. In particular, Mahr and Torosian compared anxiety and fear of negative evaluation in a sample of 22 adults who stuttered with nonstuttering controls and adults with social phobia. FNE scores for the stuttering group did not differ significantly from nonstuttering controls but were significantly lower than scores for participants with social phobia. In addition, social anxiety and distress scores for the stuttering group were significantly higher than controls but significantly lower than participants with social phobia. The stuttering group also demonstrated significantly higher anxiety symptoms than controls and significantly lower social and agoraphobia symptoms than the social phobia group. Findings regarding anxiety and fear of negative evaluation in stuttering may be relevant for older adults who stutter. For instance, Bricker-Katz, Lincoln, and McCabe (2010) conducted a qualitative study of 11 stuttering adults over the age of 55 years; the authors reported that some participants continued to fear negative evaluation in socially evaluative situations. Further, Bricker-Katz, Lincoln, and McCabe (2009) reported that scores on the FNE for a small sample of 12 older adults who stuttered were in the social phobia range and were significantly higher than scores for a sample of 14 controls. In addition, scores on the EMAS-T for socially evaluative trait anxiety and anxiety related to physical danger were also significantly higher for older adults who stuttered Iverach et al.: Anxiety and Stuttering 223

4 than for controls, even though scores for both groups fell within the average range. These findings correspond largely with those of Messenger et al. (2004), indicating that fear of negative evaluation and socially evaluative anxiety may be apparent for older adults who stutter. Anxiety and fear of negative evaluation have also been investigated among adolescents who stuttered. Mulcahy, Hennessey, Beilby, and Byrnes (2008) reported that a sample of 19 adolescents who stuttered exhibited significantly higher trait and state anxiety and significantly higher fear of negative evaluation than 18 nonstuttering controls. This suggests that increased anxiety and fear of negative evaluation for those who stutter have the potential to commence during the socially difficult adolescent years (Huber, Packman, Quine, Onslow, & Simpson, 2004, p. 176). However, further research regarding the development of fear of negative evaluation and social anxiety among children and adolescents is required. Overall, the above findings highlight the potential for stuttering to be associated with fear of negative evaluation and expectancies of social harm. This corresponds with a growing body of evidence regarding the presence of social anxiety or social phobia among people who stutter (Schneier, Wexler, & Liebowitz, 1997; Stein, Baird, & Walker, 1996), to be discussed below. Trait Anxiety Measures The second methodological issue identified by Menzies et al. (1999) related to the use of trait anxiety measures in stuttering research. Menzies et al. criticized the administration of trait anxiety measures in situations characterized by heightened state anxiety, such as making a phone call. A further criticism was drawn against the use of unidimensional measures of trait anxiety such as the State-Trait Anxiety Inventory (STAI; Spielberger et al., 1983), which regard anxiety as a single or global construct. More recent conceptualizations of anxiety have highlighted its multidimensional nature (Endler et al., 1991). Consequently, unidimensional measures of anxiety may not be sensitive enough to detect or discriminate between the various facets of speech-related anxiety for people who stutter (Ezrati-Vinacour & Levin, 2004; Menzies et al., 1999) and have subsequently yielded mixed results in the field of stuttering (Craig & Tran, 2006). Hence, the previous lack of research regarding the multidimensional nature of anxiety in stuttering may in part explain why fine tendencies in the stuttering-anxiety connection have not been detected (Ezrati-Vinacour & Levin, 2004, p. 138). Since the Menzies et al. (1999) review, one of the most significant methodological improvements in stuttering research has been the use of self-report measures and diagnostic assessments of anxiety and social phobia. These studies build on the important work of earlier research (e.g., Schneier et al., 1997; Stein et al., 1996) and contribute to a growing body of evidence regarding the presence of social anxiety or social phobia in adults who stutter. Social phobia, in particular, is characterized by significant, excessive, and persistent fear of humiliation, embarrassment, or negative evaluation in social interactional situations (e.g., initiating or maintaining conversations, meeting new people, being assertive, or speaking to authority figures) and performance situations (e.g., public speaking or performing in front of others; American Psychiatric Association, 2000; Orsillo & Hammond, 2001). Prior to the Menzies et al. (1999) review, Stein et al. (1996) and Schneier et al. (1997) contributed valuable research evidence regarding the presence of social anxiety and social phobia in adults who stutter. This evidence base has grown considerably since the Menzies et al. review with the addition of larger scale studies. For instance, Kraaimaat et al. (2002) administered a social anxiety inventory to a sample of 89 adults who stuttered and 131 nonstuttering controls. In their study, the stuttering group demonstrated significantly higher emotional discomfort in social situations than the controls did, and the stuttering group also reported significantly less social response than controls. Further, scores for the stuttering group on emotional discomfort in social situations were comparable to a normative sample of psychiatric patients, even though they were lower than scores for psychiatric patients diagnosed with social phobia. These findings correspond somewhat with those previously reported by Mahr and Torosian (1999), who found that adults who stuttered demonstrated significantly increased anxiety symptoms and social avoidance and distress than nonpatient controls, yet when compared to social phobics, they exhibited significantly lower fear of negative evaluation, social avoidance, and distress, and fewer social phobia and agoraphobia symptoms. However, more comprehensive evidence regarding social anxiety and stuttering has been obtained in studies that have used diagnostic assessments of anxiety rather than self-report measures and inventories. It is possible that the use of such assessments may contribute a less ambiguous picture of anxiety in stuttering. For instance, in the Menzies et al. (2008) clinical trial of cognitive behavior therapy (CBT) for the treatment of anxiety in stuttering, clinical psychologists conducted comprehensive assessments with adults who stuttered to determine the presence of social phobia prior to speech treatment only versus speech treatment plus CBT. Sixty percent of the Menzies et al. sample received a social phobia diagnosis at pretreatment, but none of the participants who received CBT treatment for anxiety met criteria for social phobia following treatment. Iverach, O Brian, et al. (2009) also comprehensively evaluated the presence of anxiety disorders, including social phobia, in a large sample of 92 adults who stuttered, according to the diagnostic criteria employed by the Diagnostic and Statistical Manual of Mental Disorders (DSM IV TR; American Psychiatric Association, 2000) and the International Classification of Diseases (ICD-10; World Health Organization, 1993). When compared with matched controls, the stuttering adults exhibited six- to sevenfold increased odds for any DSM IV TR or ICD-10 anxiety disorder and 16- to 34-fold increased odds for DSM IV TR or ICD-10 social phobia. This same sample of adults seeking treatment for stuttering were also found to be at increased risk of meeting first-stage screening criteria for anxious personality disorder (Iverach, Jones, et al., 2009b), which is considered to beamoresevereformofsocialphobia(reich,2000). In a related manner, Blumgart et al. (2010) investigated social anxiety in a large sample of 200 adults who stuttered 224 American Journal of Speech-Language Pathology Vol August 2011

5 and 200 nonstuttering adults by administering a variety of anxiety measures, including the STAI, the FNE, and the Social Phobia and Anxiety Inventory (Turner, Beidel, & Dancu, 1996). In addition, the Psychiatric Diagnostic Screening Questionnaire (Zimmerman & Mattia, 2001) was used to screen for social anxiety disorder (also known as social phobia) and generalized anxiety disorder in a subsample of 50 adults who stuttered and 50 controls. Results revealed that the adults who stuttered had significantly higher trait and social anxiety than the controls, with moderate to large effect sizes. Of particular interest, the adults who stuttered had significantly elevated specific fears about embarrassing themselves in situations such as public speaking, eating in public, saying stupid things, asking questions in a group, business meetings, and social gatherings or parties. Further, in the Blumgart et al. study, the stuttering group demonstrated a significantly higher risk for social anxiety disorder than controls, indicating a spot prevalence of 46%. This estimate corresponds with the prevalence rate of 44% reported by Stein et al. (1996). These findings highlight the prevalence of anxiety and social phobia among adults who stutter. However, findings by Blumgart et al. (2010) and Iverach, Jones, et al. (2009b) should be viewed with caution on the grounds that they used screening instruments rather than full diagnostic interviews to evaluate the presence of social anxiety disorder (Blumgart et al., 2010) and anxious personality disorder (Iverach, Jones, et al., 2009b). Also, of course, a caveat to those findings is that they pertain to clinical cohorts and cohorts seeking self-help group support. 1 Despite this, advances in the methods used to assess anxiety in stuttering allow us to more fully appreciate the nature of this relationship. That is, they provide a methodological leap from the unidimensional anxiety measures that have been used before. However, a number of studies since the Menzies et al. (1999) review have continued to employ unidimensional or trait measures of anxiety. For instance, Alm and Risberg (2007) investigated trait anxiety and neuromuscular activity in a sample of 32 adults who stuttered and 28 controls. The stuttering group demonstrated significantly higher trait anxiety when compared with controls, but trait anxiety was not found to be related to sensorimotor activity, as evaluated by the startle response. In addition, Blomgren et al. (2005) investigated the affective functioning of 19 adults who completed a 3-week intensive stuttering modification treatment program. Although significant improvements in psychic and somatic anxiety were found up to 6 months posttreatment, trait and state anxiety as measured by the STAI was not found to decrease significantly over the same posttreatment period. Ezrati-Vinacour and Levin (2004) also compared anxiety in 47 adults who stuttered and 47 nonstuttering controls. Trait anxiety, as measured by the STAI, was higher in the stuttering group when compared with controls, and state anxiety in social communication was higher for severe stutterers when compared with mild stutterers and nonstuttering controls. 1 Methodological issues with the Iverach, Jones, et al. (2009a) report have been discussed extensively elsewhere: Manning and Beck (2011) and Iverach, Jones, et al. (2011). That is, state anxiety, but not trait anxiety, was found to be associated with stuttering severity, whereby individuals with more severe stuttering were found to exhibit higher state anxiety. Ezrati-Vinacour and Levin concluded that anxiety is a personality trait that gradually develops over time for people who stutter. In addition, Craig et al. (2003) conducted a randomized population study of the prevalence of stuttering in 4,689 Australian households. Trait anxiety scores for 63 residents identified as people who stuttered were compared with scores from a sample of 102 matched controls from a previous study (Craig, 1990). Although trait anxiety scores for adults in the stuttering group who had not received stuttering treatment did not differ from nonstuttering controls, scores for adults who had received previous treatment for stuttering did differ significantly from nonstuttering controls. However, no significant differences in anxiety were found between stuttering adults who had received stuttering treatment and those who had not, or between those with more or less severe stuttering. Overall, Craig et al. concluded that assessments of anxiety in adults who stutter may be influenced by whether participants have received previous stuttering treatment or whether they are currently seeking treatment. A number of the above-mentioned studies attributed discrepancies and ambiguities in their findings to the complex and multidimensional nature of anxiety, as highlighted by Menzies et al. (1999). That is, by treating anxiety as a single construct, the STAI limits the ability to detect the presence of specific dimensions of anxiety (Blomgren et al., 2005) and may not be sensitive enough to measure, or differentiate between levels of, speech-related anxiety experienced by adults who stutter (Ezrati-Vinacour & Levin, 2004). Despite this, unidimensional trait anxiety measures have also been used in a small number of studies of anxiety in children and adolescents who stutter. According to Craig and Tran (2005), however, very few of these studies have reported significant differences between stuttering and nonstuttering participants. For instance, Hancock et al. (1998) investigated the long-term effectiveness of three stuttering treatments in a large sample of children and adolescents age 11 to 18 years, as originally reported by Craig et al. (1996). Seventy-seven participants completed the STAI for children at 12 months posttreatment, and 62 participants completed the STAI for children between 2 and 6 years posttreatment. No significant differences in state or trait anxiety were found between groups or over time. Similarly, Davis, Shisca, and Howell (2007) investigated state and trait anxiety in a sample of children and adolescents age 10 to 17 years, including 18 participants with persistent stuttering, 17 who had recovered from stuttering, and 19 nonstuttering controls. To evaluate trait anxiety, participants completed the STAI for children. State anxiety was assessed with a scale consisting of four different speakingrelated situations, including asking for help in a shop, talking on the phone to a friend, talking with a group of friends, and answering a question in class. Overall, trait anxiety was not found to differ significantly between groups, although the persistent group exhibited higher state anxiety on three of the four speaking situations than the recovered and control groups. Iverach et al.: Anxiety and Stuttering 225

6 Finally, Mulcahy et al. (2008) also used the STAI and the FNE to assess social anxiety in a sample of 19 adolescents who stuttered in comparison with 18 nonstuttering controls. In their study, the stuttering group demonstrated significantly higher state, trait, and social anxiety than controls. Furthermore, state and trait anxiety for the stuttering group was significantly associated with communication difficulties in daily situations. Again, it is possible that the inconsistent nature of findings in these studies may, in part, be attributable to the use of unidimensional trait anxiety measures. As suggested by Menzies et al. (1999), more consistent results may be obtained with multidimensional measures of anxiety among children and adolescents who stutter, such as the Revised Children s Manifest Anxiety Scale (RCMAS; Reynolds & Richmond, 2000). The RCMAS evaluates the level and nature of anxiety symptoms in children and adolescents and is composed of four nonoverlapping subscales regarding physiological anxiety, worry/oversensitivity, social concerns/concentration, and social desirability. Blood and Blood (2007) utilized the RCMAS in their investigation of anxiety and vulnerability to bullying in 18 children who stuttered and 18 nonstuttering controls, age 11 to 12 years. In comparison with controls, the stuttering group demonstrated a significantly higher total RCMAS anxiety score and a significantly higher score on the social concerns scale, indicating heightened anxiety regarding the expectations of others. Blood, Blood, Maloney, Meyer, and Qualls (2007) also investigated the relationship between anxiety and self-esteem in a sample of 36 adolescents who stuttered and 36 adolescents who did not stutter. Although scores on the RCMAS were within the normal range for the large majority of participants in both the stuttering and control groups, the stuttering group demonstrated significantly higher levels of anxiety when compared with the controls. Overall, further studies are required regarding the development of anxiety and social phobia in children and adolescents who stutter. This would include the use of direct measures or diagnostic assessments of social anxiety. We concur with Davis et al. (2007) that the work on children who stutter is of great potential importance as it may provide an indication about the role of anxiety in the development of stuttering ( p. 400). In sum, the accumulation of research evidence since the Menzies et al. (1999) review has improved our understanding of anxiety and stuttering with the implementation of diagnostic assessments and multidimensional measures of anxiety and social phobia. However, mixed results continue to emerge when unidimensional trait anxiety measures are employed. Regardless, the current evidence base highlights the urgent need for clinical assessment, management, and treatment of anxiety and social phobia among adults who stutter (Iverach, O Brian, et al., 2009). Implications for treatment will be discussed below. Participant Numbers The third methodological issue identified by Menzies et al. (1999) pertained to the application of small sample sizes and insufficient statistical power. In particular, Menzies et al. stated that the issue of statistical power may not be critical in cases where a significant difference between groups is identified, yet it is of substantial importance in cases where there is insufficient power to detect a significant difference. Hence, Menzies et al. suggested that insufficient power in a large proportion of research studies regarding the presence of anxiety in stuttering may have resulted in the failure to obtain significant results. Therefore, they advocated the use of more rigorous methods and sample sizes based on power calculations, with a minimum 80% chance of detecting a significant effect or difference. Other authors have echoed this call (Craig, 1990; Craig & Tran, 2006). For instance, Craig et al. (2003) suggested that small participant numbers in studies investigating anxiety and stuttering have potentially increased the risk of committing Type II statistical errors, thereby restricting the ability to detect true differences between stutterers and nonstutterers in terms of anxiety levels, as well as failing to guarantee a representative sample. In addition, Craig and Tran (2006) recently identified 20 studies that investigated anxiety in people who stuttered in comparison with nonstuttering controls. Of these 20 studies, 13 concluded that adults who stuttered were more anxious than controls, whereas seven studies did not find a significant difference in anxiety levels between groups. Of particular interest, Craig and Tran reported that the seven studies reporting nonsignificant results had a mean of 20 participants per group, whereas the 13 studies with significant differences between groups had a mean of 50 participants per group. This discovery supports Menzies et al. s (1999) claim that insufficient power may be one factor responsible for the lack of consistency in findings regarding anxiety and stuttering. However, a number of studies during the last decade have employed medium to large sample sizes and have reported significant findings (e.g., Ezrati-Vinacour & Levin, 2004; Ginsberg, 2000; Kraaimaat et al., 2002). Other studies have also conducted power analyses to determine suitable sample sizes (e.g., DiLollo, Manning, & Neimeyer, 2003). For instance, in evaluating the presence of DSM IV TR and ICD-10 anxiety disorders in a large sample of 92 adults who stuttered and 920 matched controls, Iverach, O Brian, et al. (2009) reported 80% power to detect 2.5 increased odds with a 5% level of significance. In addition, Blumgart et al. (2010) reported higher than 90% power to detect a significant difference in social anxiety between 50 adults who stuttered and 50 controls. Other studies since the Menzies et al. (1999) review have reported significant results with moderate to large sample sizes, although not all of these have conducted power analyses to confirm the ability to detect significant differences between groups. For instance, Iverach, Menzies, et al. (2011) investigated the prevalence of social phobia and anxious personality disorder in a sample of 140 adults who stuttered, and the authors found that roughly one quarter of participants met criteria for social phobia, and roughly one third of participants met screening criteria for anxious personality disorder. Ezrati-Vinacour and Levin (2004) also found that trait anxiety for a sample of 47 adults who stuttered was higher than 47 nonstuttering controls. Furthermore, Kraaimaat et al. (2002) also reported significant differences between 89 adults who stuttered and 131 nonstuttering controls in terms of emotional discomfort in social situations. 226 American Journal of Speech-Language Pathology Vol August 2011

7 Significant results have also been reported with small to moderately sized samples of adults and adolescents who stuttered (e.g., Alm & Risberg, 2007; Blood et al., 2007; Craig et al., 2003; Gabel, Colcord, & Petrosino, 2002; Mahr & Torosian, 1999; Menzies et al., 2008; Mulcahy et al., 2008). However, a number of other studies have utilized small to moderate samples of people who stuttered and have reported less consistent results. For example, Dietrich and Roaman (2001) investigated the extent to which perceptions of speech-related anxiety correlated with physiological arousal in specific speaking situations in a sample of 24 adults who stuttered; they found no correlation between predictions of speech-related anxiety in 20 hypothetical speaking situations and skin conduction responses during enactment of four speaking situations. Similarly, Davis et al. (2007) reported no significant differences in trait anxiety between 35 adolescents and children who stuttered and 19 nonstuttering controls. However, state anxiety for participants with persistent stuttering was found to be higher than for participants who had recovered from stuttering and nonstuttering controls. Furthermore, Blomgren et al. (2005) reported that state and trait anxiety (as measured by the STAI) was not found to change following stuttering treatment with a sample of 19 adults who stuttered. Overall, it appears that use of larger sample sizes in the stuttering literature since the Menzies et al. (1999) review has resulted in a less ambiguous picture of the relationship between anxiety and stuttering. However, this increased clarity of evidence may also stem from the use of measures of anxiety and social phobia that are multidimensional or diagnostic in their assessment. Regardless, it is imperative for future research in this area to contain a priori power analyses to ensure sufficient statistical power to detect significant differences. Treatment Status of Participants The fourth methodological issue identified by Menzies et al. (1999) pertained to the treatment status of participants. In particular, it has been suggested that research findings regarding the link between anxiety and stuttering may be confounded by the inclusion of both treated and untreated adults who stutter (Craig, 1990; Craig et al., 2003; Craig & Tran, 2006). For instance, Craig has argued that speech treatment may potentially reduce anxiety and negative expectancies, which means that the inclusion of adults who have received treatment for stuttering has the potential to reduce the likelihood of identifying anxiety in stuttering samples. This may also be the case for adults who are attending stuttering support groups (e.g., Mahr & Torosian, 1999). Given the difficulties inherent in obtaining sizable samples of adults who stutter but have never received treatment, Menzies et al. (1999) suggested that future research would benefit from dividing samples into those who have and have not received treatment, thereby gauging the potential impact of speech treatment on anxiety levels. At the time of the Menzies et al. review, no study had divided samples based on treatment status, nor had any study investigated the presence of anxiety in a sample composed only of untreated adults who stuttered. Changes regarding the treatment status of participants since the Menzies et al. (1999) review have been lacking. In particular, the large majority of studies regarding anxiety and stuttering have included samples of adults who had received treatment in the past or who were currently seeking or receiving treatment for stuttering (e.g., Blomgren et al., 2005; Blumgart et al., 2010; Ezrati-Vinacour & Levin, 2004; Gabel et al., 2002; Ginsberg, 2000; Iverach, Menzies, et al., 2011; Iverach, O Brian, et al., 2009; Kraaimaat et al., 2002; Mahr & Torosian, 1999). This has also been the case in studies of children and adolescents who stutter (e.g., Blood et al., 2007; Davis et al., 2007; Mulcahy et al., 2008). To our knowledge, only one study since the Menzies et al. (1999) review has divided samples into participants who have and have not received treatment for stuttering (Craig et al., 2003). As previously mentioned, Craig et al. (2003) conducted a randomized population study to investigate anxiety in treated and untreated adults who stuttered. Of 63 stuttering adults who completed the STAI, 33 reported no previous treatment for stuttering. Trait anxiety for these 33 participants did not differ significantly from nonstuttering controls, yet stutterers who had received previous treatment demonstrated significantly higher trait anxiety than controls. These findings suggest that there may be differences in anxiety levels for adults who received treatment for stuttering versus those who have not received treatment. In sum, the above research suggests a difficulty inherent in recruiting stuttering samples from those who have never sought treatment for stuttering. Further research is required to determine whether differences in anxiety exist between samples of treated and untreated adults who stutter. In addition, it may be useful for future research to investigate whether adults who are currently seeking treatment are more or less anxious than adults who have received treatment in the past but who are not currently seeking treatment. Having said this, the comorbid presence of anxiety and stuttering may increase the chances that an individual will seek treatment for his or her stuttering (Iverach, O Brian, et al., 2009). Furthermore, it is likely that adults who stutter may have an increased risk of experiencing anxiety regardless of whether they have received treatment for stuttering (Craig et al., 2009). Speaking Tasks The final methodological issue highlighted by Menzies et al. (1999) pertained to the use of single speaking tasks (e.g., speaking on the telephone) to elicit or manipulate anxiety in people who stutter. In particular, Menzies et al. argued that no single speaking task is capable of eliciting anxiety in all participants, and the authors suggested that future research would benefit from the use of individualized behavioral assessment tasks to maximize the chances of eliciting and detecting anxiety. That is, participants could be assigned individualized behavioral tasks specifically aimed at maximizing the experience of anxiety, rather than simply assigning the same task for all participants. Since the Menzies et al. (1999) review, only a small number of studies have attempted to manipulate anxiety in people who stutter. Of particular note, Gabel et al. (2002) investigated differences in self-reported anxiety for 10 adults who Iverach et al.: Anxiety and Stuttering 227

8 stuttered and 10 matched controls. In a similar manner to in vivo cognitive assessments used in cognitive behavioral treatments, all participants rated their anxiety at specific moments during a diagnostic speech assessment, including (a) three baseline reports, (b) four reports during a period in which they were thinking about their speech ( the thinking period ), and (c) six reports during speaking tasks ( the speaking period ). Overall, the adults who stuttered reported significantly more anxiety throughout the diagnostic assessment than controls and were more likely to report anxiety in speaking situations than in other situations. Similarly, Ezrati-Vinacour and Levin (2004) developed an assessment of task-related anxiety for their sample of 47 adults who stuttered and 47 controls. Participants were asked to evaluate their anxiety after performing two speech tasks and two nonspeech tasks: (a) a conversation about personal information, (b) reading a passage aloud, (c) silent reading of a passage, and (d) listening to a recorded passage. Participants rated their anxiety in each of these situations on a scale ranging from extremely anxious to not at all anxious. Anxiety in speech-related tasks was found to be higher for adults with more severe stuttering, indicating that stuttering severity may play a role in the experience of anxiety in social communication situations. These studies provide valuable information about the assessment of anxiety across multiple tasks. However, the anxiety assessments used in both studies were not inclusive of a wide range of anxiety-provoking situations for people who stutter (e.g., ordering food, taking in front of a group, or talking in a public place), nor were they individually assigned to maximize the experience of anxiety for individual participants. Further limitations also apply to other studies that have attempted to evaluate anxiety across speaking tasks. For instance, although Davis et al. (2007) evaluated participants self-perceived state anxiety in four different speaking situations, this was done by self-report, not by actual exposure to these situations. Likewise, a small number of studies have also utilized routine and challenging phone calls as the basis for calculating stuttering frequency for adults who stuttered in their samples, including ratings of participants subjective units of distress following each call to gauge how anxiety-provoking the phone call was (e.g., Iverach, Jones, et al., 2009a; Menzies et al., 2008). However, these studies did not include any other individually assigned behavioral tasks specifically aimed at eliciting anxiety. To our knowledge, only one study since the Menzies et al. (1999) review has utilized individualized behavioral experiments as a means of treating anxiety in adults who stutter. Helgadottir, Menzies, Onslow, Packman, and O Brian (2009b) reported on the use of a web-based CBT program for the treatment of anxiety in two stuttering adults diagnosed with social phobia. As part of the computerized program, participants engaged in individually formulated behavioral experiments to facilitate exposure to feared situations or experiences. This also included the provision of additional cognitive restructuring exercises. Therefore, the methodological issues regarding speaking tasks used in stuttering research as raised by Menzies et al. still requires attention in future research and may benefit from applications to treatment of anxiety in adults who stutter. Further Considerations In addition to the methodological issues outlined above, a number of further considerations pertain to future research regarding the relationship between anxiety and stuttering. The Development of Anxiety Across the Lifespan Since the Menzies et al. (1999) review, a number of studies have contributed to our understanding of anxiety in children and adolescents who stutter (e.g., Blood & Blood, 2007; Davis et al., 2007; Mulcahy et al., 2008). However, we currently know very little about the development of anxiety in children (Furnham & Davis, 2004). Studies regarding the progression of anxiety over the lifespan could be of significant benefit to our understanding of the etiology, management, and treatment of anxiety (Craig & Tran, 2005). In particular, Craig and Tran (2005) have suggested the following: What is really needed is an investigation that measures the progression of anxiety in PWS [ people who stutter] in the community using randomized and stratified selection procedures. Such a sample is far more likely to provide data representative of the population of people who stutter. (p. 44) This could also include investigations regarding differences between stuttering people who develop social anxiety and those who do not (Craig & Tran, 2006). The Relationship Between Anxiety and Stuttering Severity There are some indications in the literature that a relationship may exist between anxiety and stuttering severity. However, current research evidence regarding this relationship is inconclusive. For instance, Blumgart et al. (2010) reported that stuttering severity was not associated with any anxiety measure or with increased symptoms of social anxiety disorders. Other studies have also reported a null relationship between stuttering severity and trait anxiety (e.g., Alm & Risberg, 2007; Ezrati-Vinacour & Levin, 2004; Miller & Watson, 1992), between stuttering severity and social phobia (Menzies et al., 2008), and between pretreatment stuttering severity and the presence of mental health disorders (Iverach, Jones, et al., 2009a). However, Ezrati- Vinacour and Levin (2004) reported that adults in their sample with more severe stuttering exhibited higher state anxiety. Craig et al. (2009) have also suggested that stuttering severity may increase the risk of poorer emotional functioning. Perhaps these inconsistent findings relate to the different strategies used by those affected to cope with stuttering (Plexico et al. 2009). Therefore, future research would benefit from explorations of the relationship between stuttering severity and the experience of anxiety in social situations. Treatments for Anxiety in Stuttering Ingham s (1984) review mentioned a number of anxietymodification techniques used to treat stuttering, including reciprocal inhibition, hypnotherapy, drug therapy, and biofeedback. He noted the use of reciprocal inhibition therapy 228 American Journal of Speech-Language Pathology Vol August 2011