The Comprehensive Stuttering Program and Its Evidence Base

With regard to self-report data, S-24 pre-treatment and 10-year follow-up data were available for 10 participants and SPQ data were obtained from 12 participants at 10 years follow-up. The pre-treatment and 10-year means for the S-24 were 16.6 (SD = 5.72) and 8.5 (SD = 3.95), respectively. The difference in means was statistically significant (t (9) = 4.79) and the effect size was large (d = 1.67). With regard to the SPQ, at 10 years follow-up the majority of participants who responded reported that (1) they were generally satisfied with their current speech, (2) they had the ability to use techniques to control speech most of the time or more often, (3) their confidence in their ability to speak improved and (4) they had to pay attention to speech most of the time or almost always to be fluent.

Advantages and disadvantages

Advantages

A strength of the CSP is its integrated treatment approach in that it targets overt stuttering as well as the attitudinal and emotional consequences of the disorder. The CSP was developed to address both the overt and the psychological, attitudinal and emotional consequences of the disorder. This approach was and continues to be supported by substantial evidence of anxiety (Menzies et al., 1999) and social anxiety disorders (e.g. Menzies et al., 2008) in individuals who stutter, acknowledgement of the need to include cognitive behavioural therapy in stuttering treatment programmes (Menzies et al., 2008; Webster and Poulos, 1989) and the need to address negative cognitions and emotions (Plexico et al., 2005).

Another strength of the CSP is its evidence base; however, there are also limitations that must be addressed in future research. Evidence of efficacy has been provided in five studies, all of which provide Phase II levels of evidence for participants in intensive treatment programmes. That is, based on Robey’s (2004) five-phase model for clinical outcome research in the communication sciences, the main statistical goal of Phase II levels of evidence is to provide indications of the presence and magnitude of efficacy through point and interval estimates of effect size. The standardised effect sizes reported in the CSP studies for stuttering reductions have primarily been large, and effect sizes for improvements in perceptions of stuttering, communications attitudes and confidence have all been large.

A further strength of the CSP is the independent replication of the programme. Jehle (1995a) and colleagues delivered a German translation of the CSP to 25 clients. They reported that 71% of the 21 clients from whom measures were obtained at 8–11 weeks post-treatment were maintaining satisfactory (<3% stuttering) or marginally satisfactory (3% to <6% stuttering) outcomes. These results are comparable to 1 year outcomes reported in Boberg and Kully (1985). In contrast to Boberg and Kully (1985), Jehle (1995b) and colleagues included a refresher week and 5 refresher weekends that required attendance at the clinic. Immediately prior to the last refresher weekend 65% of the 20 clients from whom measures were obtained (Jehle, 1995a) were maintaining satisfactory or marginally satisfactory outcomes. However, as Jehle (1995a, 1995b) indicated, the group of clients treated presented with severe symptoms, with the group of clients having an average of 2.8 previous therapies and the range being 0–13 previous therapies (Jehle, 1995b).

Disadvantages

However, given the within-group effect design of these studies, the estimates of effect size are not generalisable to the population of adults who stutter who seek treatment. As well, without Phase III evidence involving a control group that receives no treatment, it is unknown whether the improvements achieved are the direct result of the CSP and what the real effect size might be in terms of an odds ratio. This limitation also applies to other speech restructuring programmes that have not yet used control group experimental designs.

A disadvantage of the CSP is that between 14% and 29% of participants across all CSP studies were categorised as not maintaining speech treatment gains. As Langevin et al. (2006, 2010) indicated, this finding is consistent with historical evidence (Craig et al., 1987; Franken et al., 1997; Howie et al., 1981) that there may be a subgroup of 20–30% of clients who are not able to maintain speech gains achieved in treatments that employ speech restructuring techniques. The reasons for these results with the CSP in particular are not yet known and warrant further investigation. It is possible that vulnerability to relapse is associated with pre-treatment stuttering severity. Pre-treatment stuttering severity measured in terms of %SS has been shown to be a weak but consistent predictor of poorer treatment outcomes (Block et al., 2006; Craig, 1998). With regard to graduates of the CSP, Huinck et al. (2006) found that participants who had more severe pre-treatment stuttering made greater gains but also suffered higher levels of relapse than those with less severe pre-treatment stuttering severity.

There is also evidence that individuals who stutter who have anxiety or other concomitant mental health disorders may be more vulnerable to relapse and may require treatment that focuses more purely on the concomitant mental health disorder (Iverach et al., 2009). Future research employing measures used by Iverach and colleagues is needed to determine the degree to which CSP clients have concomitant mental health disorders and whether or not such disorders are related to poorer CSP outcomes for individuals. If it is found that mental health disorders are predictive of poorer treatment outcomes in the CSP, then individuals who have concomitant mental health disorders may benefit from psychological treatment that is in place of or complements the cognitive-behavioural methods currently used in the programme. However, it is notable that differences between CSP participants categorised by Huinck et al. (2006) as having mild and severely negative emotional and cognitive reactions to stuttering at pre-treatment disappeared at post-treatment and at 1 and 2 years follow-up.

Other possibilities that may place individuals at risk for relapse is that the physiological basis to stuttering remains after treatment (Craig, 1998) or differences in neural plasticity exist (De Nil, 2004). It may also be that combinations of speech and attitudes (Craig, 1998; Guitar, 1976) or combinations of neuromotor, linguistic and emotional–motivational factors (McClean et al., 2004) contribute to vulnerability for relapse.

Conclusions and future directions

Across studies, including the data presented in the present report, outcomes for 135 clients treated in 3-week intensive programmes have been published. These outcomes have given Phase II levels of evidence that suggest that the CSP is efficacious in helping adolescents and adults achieve clinically meaningful and durable reductions in stuttering with speech naturalness being within normal ranges for typically fluent speakers at follow-up measures. Across five CSP studies, including the 10-year outcome data reported here, 71–86% of participants were categorised as maintaining reduced stuttering at 1, 2, 5 or 10 years post-treatment. As well, self-report data provide evidence of clinically significant improvements in communication attitudes, perceptions of stuttering and confidence in approaching speech situations.

Refinements of the CSP or development of new treatments are needed for the subgroup of clients who are not able to maintain stuttering reductions achieved in treatment with the CSP. As indicated previously, it may be that purely psychological treatments are needed in place of or in addition to the cognitive behavioural components of the CSP. Also, investigations using a comprehensive and holistic set of quantitative and qualitative measures is needed to more fully investigate the clinical significance of treatment outcomes and the process of maintenance from the perspective of clients and significant others. Finally, given the worldwide problem of limited accessibility to stuttering treatment (Carey et al., 2010; Pickering et al., 1998) there is a need to investigate the feasibility of using telehealth solely to deliver the CSP. Since 1998, ISTAR has been using telehealth to deliver refresher therapy for those adolescents and adults who complete intensive programmes and for children in non-intensive programmes (Haynes and Langevin, 2010, 2011; Kully, 2000, 2002; Loheim et al., 2011). However, given that approximately 70% of clients who come to ISTAR live outside of the two cities in which its offices are located, investigations of outcomes for treatment delivered solely through telehealth are of urgent need.

Discussion

Ann Packman
Marilyn, our group was excited by your 10 years of data and all the outcomes you measured during that period. We were interested in your definition of relapse, so could you elaborate?
Marilyn Langevin
One aspect of our determination of sustained, clinically meaningful stuttering reductions is based on percent syllables stuttered at pre-treatment relative to follow-up. In order to be considered as not being in relapse by us, that score needs to be 50% or greater. Or put another way, we consider our clients to maintain their treatment benefits if they continue have 50% stuttering improvement or more.
Ann Packman
This is not a criticism, but is that figure arbitrary?
Marilyn Langevin
It is essentially arbitrary, based to some extent on what clients tell us. If someone stutters at 60 %SS and sustains a 50 percent improvement of 30 %SS at follow-up, they will often tell us that they are doing well. Of course, this method is not perfect. For example, if someone is mild at 3 %SS pre-treatment and 2 %SS at follow-up, but has fewer of the disruptive type of stutters, then according to the criterion relapse has occurred but overall stuttering severity is less. We are trying to improve what is obviously a limited system for defining relapse. There are statistical procedures for determining clinically meaningful change that might be of value, and we are currently looking into that. One thing I didn’t mention, incidentally, is that we tested for significant differences between follow-up measures 1–4 years post-treatment, to determine the stability of results, and there were no significant differences.
Joseph Attanasio
Marilyn, our group too wants to compliment you and your colleagues at ISTAR for such a commitment to evidence-based practice and the willingness of your clinicians to be part of that. One of our questions concerns the many components of the CSP. If you needed to simplify the programme, which components would you keep and which would you eliminate?
Marilyn Langevin
I would definitely keep the speech restructuring for stuttering control because obviously that’s foundational. The speech pattern we use comprises ‘easy breathing’, ‘gentle starts’, ‘smooth blending’, which is keeping airflow moving and moving speech forward and ‘light touches’, which is similar to what others refer to as ‘soft contacts’. If I had to trim those I think I would keep the ‘smooth blending’ because it incorporates breathing; you need to get air past the vocal folds in order to create sound (see Kully et al., 2007). Actually I am intrigued with the idea from Packman et al. (1994) that speech restructuring might induce acoustical changes that we have not been able to measure. I would keep the Van Riperian ‘pull outs’, but if I could only pick one it would be the tension reduction because although its mechanism is not clear – it might be respiratory, laryngeal, articulatory or some combination of them – it is critical for clients to reduce the tension. I think we need to retain the cognitive behavioural components, but maybe we can reduce the steps in the procedure. For those clients who are in need, I definitely would continue our referral practices to clinical psychologists who are licensed for cognitive behaviour therapy.
Sheena Reilly
Your 5–10 year outcomes look great and really promising. Can you predict the 20–30% who have poor outcomes and do you have any information about their case histories after treatment? Are they clients who have had previous treatments? Are the successful clients those who come for refresher courses?
Marilyn Langevin
The majority of adult clients who come to ISTAR have had previous treatment. We really don’t know whether that helps or hinders their success in CSP. Of course, some of them have had negative treatment experiences in the past, and that certainly doesn’t help. Generally with CSP the number of clients who receive refresher courses is quite small.
Sheena Reilly
Do you know how many of your participants sought other treatments during the 10-year follow-up period?
Marilyn Langevin
No, we don’t unfortunately. But that of course is a well-known problem with directly determining long-term effects of speech restructuring treatments for adults. The longer the follow-up with a clinical trial, the less certain you can be that the original treatment is responsible for any observed stuttering reductions, and that is a problem that cannot really be solved with, say, a 10-year control group. The only way to really know is with an epidemiological study, and to my knowledge no such study has been published.
Ann Packman
You mentioned simplifying or shortening the cognitive behaviour therapy component. There now exists a scale that documents 66 unhelpful thoughts and beliefs about stuttering which appear to drive the social anxiety of those who stutter (Iverach et al. (2011); Clare et al. (2008)). Would that be any value for such simplification or shortening of that component?
Marilyn Langevin
I have looked at that checklist and compared it to my list of self-talk statements that have been collected over my entire career doing the cognitive behaviour therapy component of the CSP. There are few items on my list that aren’t included there. I have to say I want a reduced list. So I am waiting for future simplification of that scale. Such simplification happens often during scale development. I think structural equation modelling might be a useful approach to identify factors in there, so that a 10 or 15 item scale can be developed.
Joseph Attanasio
Our group wondered how you decide who gets individual, group, intensive or non-intensive CSP treatment. Is there a screening process you use?
Marilyn Langevin
We do not have a formal screening process. We consider stuttering severity and response to clinical probes. For example, in our assessments we determine the ease with which potential clients acquire fluency skills. We also make judgments based on the type of stuttering they present with. If they are extremely tense and their breathing is severely disrupted, and if we feel that they will need all the skills we can teach, we would enrol them in the 3-week programme. On other occasions, we may wish to use an individual, non-intensive treatment programme, or even a 4-day intensive programme. We also take into account where they live. If they are living remotely, we may use the shorter intensive format then follow-up with telehealth maintenance. Telehealth technologies include interactive videoconferencing, secure web conferencing via Adobe Acrobat, Connect Pro Meeting, Skype, transmission of audio/video samples via mail or electronically and telephone calls, or a combination of these.
Sheena Reilly
We don’t expect you to have an answer for this, but we think it would be a really interesting thing to reflect on. What’s the way forward for conducting trials with adolescents and adults? You talked about wanting to move to a randomised controlled trial eventually. There are many independently replicated Phase I and Phase II trials of speech restructuring, and two randomised controlled trials (Carey et al., 2010; Cream et al., 2010). It seems incontrovertible that speech restructuring treatment is an efficacious method for stuttering control. So, do you think you could at present ethically conduct a trial with a no-treatment control group?
Marilyn Langevin
My view is that a randomised controlled trial could be conducted with a wait list control. We could conduct a comparison of the CSP and a modified CSP along the lines I mentioned earlier. However, I think the most pressing clinical research need for the treatment is to improve understanding of what happens in maintenance.
Sheena Reilly
Do you think no-treatment control groups are possible now? Do you think anyone would be willing to participate?
Marilyn Langevin
I think a waitlist control is feasible. But people come to ISTAR wanting treatment, so perhaps a trial with a 1-year control arm is not feasible.
Sheena Reilly
Then we get into the inadequate follow-up issue, and it becomes tricky.
Ann Packman
Marilyn, our group was interested in the ages of your clients, what is your lowest age limit and would you extend it to below that? How would you modify the CSP for young children?
Marilyn Langevin
The usual minimum age for the intensive programme is 16 years. For kids that age and 17 years it usually works for them to be with the older group of clients. With 14- and 15-year olds we will make a case-by-case decision, but we will make some modifications for their treatment, particularly with the cognitive behaviour therapy component. This involves breaking up to two groups for that treatment component during the intensive. We do treat school-age children by modifying CSP for them but retaining the essential speech restructuring components. And for that age, the cognitive behaviour therapy often needs to focus on bullying, which is of course a well-known issue for that age group.

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