An evidence-based systematic review on communication treatments for individuals with right hemisphere brain damage

PURPOSE

The purpose of this review is to evaluate and summarize the research evidence related to the treatment of individuals with right hemisphere communication disorders.

METHOD

A comprehensive search of the literature using key words related to right hemisphere brain damage and communication treatment was conducted in 27 databases (e.g., PubMed, CINAHL). On the basis of a set of pre-established clinical questions, inclusion/exclusion criteria, and search parameters, studies investigating sentence- or discourse-level treatments were identified and evaluated for methodological quality. Data regarding participant, intervention, and outcome variables were reported.

RESULTS

Only 5 studies were identified, each representing a different sentence- or discourse-level treatment approach and reporting a wide range of prosodic, expressive, receptive, and pragmatic outcomes.

CONCLUSION

Although the state of the evidence pertaining to right hemisphere communication treatments is at a very preliminary stage, some positive findings were identified to assist speech-language pathologists who are working with individuals with right hemisphere brain damage. Clinical implications and recommendations for future research are explored.

Phonological and phonetic marking of information status in Foreign Accent Syndrome

BACKGROUND

Foreign Accent Syndrome (FAS) is a motor speech disorder in which a variety of segmental and suprasegmental errors lead to the perception of a new accent in speech. Whilst changes in intonation have been identified to contribute considerably to the perceived alteration in accent, research has rarely focused on how these changes impact on the pragmatic use of intonation. However, a greater understanding of the role of intonational changes in FAS and its impact on the functional use of intonation is fundamental to developing appropriate assessment and subsequently treatment strategies for FAS.

AIMS

This study investigated intonation patterns in speakers with FAS and matched control participants with regard to their ability to signal new and given information (information status) within sentences. A phonetic and phonological perspective was taken with the aim of identifying the characteristics that were compromised in FAS to convey this linguistic function.

METHODS & PROCEDURES

Four speakers with FAS and four control participants participated in the speech production experiment. The speech data were assessed perceptually, and examined in relation to the use of the phonetic parameters fundamental frequency (f0), intensity and duration as well as phonological categories, i.e. pitch accents and de-accentuation, using the autosegmental-metrical (AM) framework of intonational analysis.

OUTCOMES & RESULTS

Both speaker groups employed all three phonetic parameters to differentiate between new and given information. However, groups differed regarding the use of phonological markers, with speakers with FAS frequently placing pitch accents on given information instead of de-accenting these elements. According to the perceptual evaluation, three of the four speakers with FAS had problems signalling information status.

CONCLUSIONS & IMPLICATIONS

The fact that speakers with FAS marked information status similarly to control speakers at the phonetic level, but failed to do so using phonological categories highlights the importance of assessing phonetic as well as phonological features to gain detailed information about the functional use of intonation in FAS.

Aphasia treatment: intensity, dose parameters, and script training

Studies of aphasia treatment have shown that intensive speech-language therapy is associated with significant improvements. However, there is no standard definition of intensity and the simplistic notion that "more is better" is not necessarily supported by the research. First, current evidence regarding intensity and aphasia treatment was briefly summarized. Second, studies that directly compare conditions of higher- and lower-intensity treatment for aphasia were reviewed with regard to the inclusion of parameters that contribute to a definition of intensity. In addition to five parameters proposed by Warren, Fey, and Yoder (2007) and highlighted by Baker (2012) , total number of sessions was also often documented. The review illustrated the complexity of quantifying the dose of comprehensive treatments that target multiple modalities and utilize a variety of different strategies. Third, data from a study reporting a relationship between intensive computer-based script training and outcomes in aphasia were examined. Results serve to illustrate Baker's contention that intensity alone is insufficient without also considering the active ingredients of the teaching episode. Information about dose, therapeutic inputs, and client acts can lead to better optimization of an intervention.

Challenges inherent in optimizing speech-language pathology outcomes: it's not just about counting the hours

Determining the optimal amount of intervention is possibly the biggest challenge facing speech-language pathologists (SLPs) today. Baker (2012) has provided an erudite and pithy summary of the relevant literature in the field of optimizing intervention outcomes, and proposed a conceptual framework to measure all the inputs and acts that may contribute to the algorithm of intervention intensity. In the following article, two issues are discussed: first, that the use of technological advances to increase intensity should focus on everyday communication outcomes and, secondly, that measuring the effects of treatments which aim to increase intensity should include the perceptions of the client. Describing the evidence-based kernels underlying treatment success is a complex endeavour, particularly when the target treatment outcome is improved conversation. A recent qualitative study is described where clients with brain injury and their families were asked about their perceptions of a communication partner training program, to help determine which part of the treatment worked and why. It is argued that such an approach may provide important information regarding the "active ingredients" of treatment success.

Studying the impact of intensity is important but complicated

This commentary suggests that the most commonly studied aspect intensity (dose frequency) on overall rate of response to treatment may often be weak or conditional. To improve statistical power of tests of weak effects additive statistical models have typically been used. However, multiplicative models may be a more productive route to understanding dose frequency effects on children's speech and language development. To illustrate, recent findings are presented that dose frequency effects on vocabulary development varied by two child characteristics. Finally, it is suggested that spacing of teaching episodes within an intervention session be included as a variable in the multi-dimensional model of treatment intensity. Spacing teaching episodes may eventually prove to be one of the more powerful aspects of intensity.

Optimal dose-response relationships in voice therapy

Like other areas of speech-language pathology, the behavioural management of voice disorders lacks precision regarding optimal dose-response relationships. In voice therapy, dosing can presumably vary from no measurable effect (i.e., no observable benefit or adverse effect), to ideal dose (maximum benefit with no adverse effects), to doses that produce toxic or harmful effects on voice production. Practicing specific vocal exercises will inevitably increase vocal load. At ideal doses, these exercises may be non-toxic and beneficial, while at intermediate or high doses, the same exercises may actually be toxic or damaging to vocal fold tissues. In pharmacology, toxicity is a critical concept, yet it is rarely considered in voice therapy, with little known regarding "effective" concentrations of specific voice therapies vs "toxic" concentrations. The potential for vocal fold tissue damage related to overdosing on specific vocal exercises has been under-studied. In this commentary, the issue of dosing will be explored within the context of voice therapy, with particular emphasis placed on possible "overdosing".

Optimal intervention intensity

Empirical evidence exists for many of the different interventions in speech-language pathology. However, relatively little is known about the optimal intensity of those interventions. In order for speech-language pathology services to be both effective and efficient speech-language pathologists need to know how to faithfully administer ideal doses of the active ingredients of interventions, in what forms, how often and for how long. This is the lead paper to a scientific forum on this fundamental yet under-studied issue of clinical practice. Borrowing from the work of Warren, Fey, and Yoder, the concept of intervention intensity is described. Issues involved in establishing the optimal intensity of interventions are identified, including what and how intervention goals are targeted. Given that speech-language pathology interventions can involve the delivery of therapeutic inputs (e.g., conversational recasts, questions) and/or clients carrying out an act (e.g., speech production, voice production, comprehending, naming, swallowing), a framework is proposed for measuring all potential inputs and acts that might contribute to the calculation of an intervention intensity. Client-, clinician-, condition-, and service-related variables that could influence the investigation and practical application of an optimal intervention intensity are also discussed.

Optimal intervention intensity in speech-language pathology: discoveries, challenges, and unchartered territories

This article is the final response in a scientific forum on the optimal intensity of intervention in speech-language pathology. It is a reflection on the state of knowledge offered by the 13 commentaries in this issue, addressing the areas of early communication and language impairment, speech sound disorders in children, emergent literacy, reading, aphasia, dysphagia, stuttering, motor speech disorders, voice disorders, and traumatic brain injury. Although more intense intervention can lead to better outcomes, the relationship between intensity and outcome is not always linear. More is not always better. Non-intense and intense schedules can yield similar outcomes. Intensity can also reach a point of diminishing return. The insights offered by the authors illustrate the challenges involved in studying this complex issue. To establish the optimal intensity of interventions in speech-language pathology our field needs to: identify active ingredients of interventions; better understand how principles of motor learning and neural plasticity facilitate learning; appreciate the contribution of individuals characteristics, values, and preferences; discover the effect of specific combinations of intensity (including dose, dose form, dose frequency, session duration, and total intervention duration) on treatment outcomes, and find practical solutions when disparities exist between research recommendations and workplace limitations.

Characterizing optimal intervention intensity: the relationship between dosage and effect size in interventions for children with developmental speech and language difficulties

Although Warren, Fey and Yoder (2007) have described the key components of "dosage", one needs to go beyond description if one is to understand "optimal" dosage, specifically one needs to relate the characteristics of the intervention to the size of the intervention effect. This study examines the association between dose, intensity, and effect size in 20 randomized controlled studies taken from a few systematic reviews focusing on interventions aiming to ameliorate vocabulary, phonology, and syntax. Reporting of dosage characteristics is an important issue. Our analysis shows that "teaching episodes" and "dose form" are rarely reported in the included studies. The other dosage characteristics are present but not always reported in a transparent fashion. Session length and cumulative intervention intensity is lower for phonology interventions than it is for vocabulary intervention. Dosage, however defined, is not directly associated with outcome, although the level of association varies across the three interventions, for example appearing stronger for vocabulary and phonology than syntax. Taking the three interventions together the dosage components are related to the intervention effects size, but the sample is small and the association is not statistically significant. This study concludes that, while the framework suggested by Baker (2012) and adapted from Warren et al. (2007) is useful but without reference to the effect size of a study, it can only ever tell half the story. One needs to be able to relate dosage to outcome, asking questions about the relationship between the different dosage characteristics and the intervention effect size. Given the available data, it is not, at this stage, possible to make recommendations about optimal dosage.

Intensity in phonological intervention: is there a prescribed amount?

Despite a number of studies that have demonstrated positive outcomes for inducing clinical change in children with speech sound disorders (SSD), there is a need to address the question of whether resources are being applied in an optimal manner. As a consequence, there has been a call to look within interventions to examine parameters that may contribute to intervention outcomes; specifically the intensity of intervention (dose, frequency, duration, and cumulative intervention intensity). In this paper, empirical evidence from three intervention studies using multiple oppositions primarily, and a second contrastive approach, minimal pairs, is reported with regard to the parameters of intervention intensity. The findings indicated that greater intensity yields greater treatment outcomes. Further, quantitative and qualitative changes in intensity occur as intervention progresses, and there were differences in intensity based on severity of the SSD. Based on these data, suggestions were made toward establishing some prescribed amounts of intensity to affect treatment outcomes for children with SSD.

Treatment intensity in everyday clinical management of speech sound disorders in Hong Kong

Much evidence supports the efficacy of different treatment approaches for speech sound disorders (SSD) in children. Minimal research in the field has been conducted using treatment intensity as a research variable. This study examined the current practice of speech-language pathologists (SLPs) in Hong Kong regarding the treatment intensity prescribed to children with SSD and potential factors that were associated with the intensity. Participants were 102 SLPs working in different settings in Hong Kong who completed an online questionnaire. SLPs who had a heavier caseload offered significantly less frequent and shorter treatment duration to clients with SSD. Public and private settings differed significantly in treatment duration. Treatment approaches and clinicians' consideration about a client's conditions did not affect treatment intensity. SLPs in Hong Kong do not plan treatment duration and frequency in an evidence-based direction because of their heavy workloads and the dearth of research evidence on treatment intensity to guide their clinical practice.

Clinical efficacy and randomized clinical trials in dysphagia

This manuscript reviews the current state of research on treatment efficacy for swallowing disorders in relation to the use of large-scale randomized multi institutional trials. Dose response trials, i.e., how much treatment is needed to achieve the desired result, are not yet available in dysphagia. The financial and medical pressures on clinicians responsible for diagnosing and treating the dysphagic patient are noted as they often impact the timing of patient care in dysphagia. The process of integration of treatment techniques into the diagnostic study (Modified Barium Swallow, videofluoroscopy) to improve the patient's swallow as quickly as possible is described. The availability of a clinical trial group, the Communications Sciences and Disorders Clinical Trials Research Group (CSDRG), is noted to assist clinicians and scientists in the development of all types of clinical trials in dysphagia.

How much therapy is enough? The impossible question!

There is sufficient evidence in the literature related to speech-language pathology, physiotherapy, occupational therapy, and psychology to indicate that intensive therapy is required in order to influence the neurophysiological basis of various impairments. Conversely, the influence of therapy on reducing communication restriction, psychosocial impact, and well-being is less well documented in speech-language pathology, but research in related areas indicates that the amount of therapy required to have a positive influence on these areas is associated with a broad range of individual and social factors. Intensive therapy takes considerable commitment on the part of the therapist, patient, and family members, and is not always achievable or acceptable. Therapists can incorporate a broad range of approaches to increase the amount of therapy available to individuals which may include expanding self-management, computerized therapy, use of the family members and volunteers, and improving skill mix. Most importantly it is essential to consider the objectives of the therapy when determining the intensity.

Investigating optimal intervention intensity with the Lidcombe Program of early stuttering intervention

This paper addresses optimal intervention intensity in stuttering with reference to the Lidcombe Program of early stuttering intervention. This is an operant program in which the parent provides the actual treatment, for proscribed periods each day, in the child's everyday environment. The parent learns how to do this during weekly visits with the child to the speech-language pathologist. This program was chosen because it is supported by considerable research evidence. This evidence includes randomized controlled trials and file audits. Individual children vary in the time taken to reach the program criteria, with children with milder stuttering taking less time than children whose stuttering is more severe. Hence, the dose depends largely on stuttering severity. Other service delivery models for the Lidcombe Program have been investigated, including telehealth (distance delivery) and group delivery. While telehealth delivery was as efficacious as face-to-face delivery, 3-times more clinician hours were needed to achieve this. Group delivery of the program was also as efficacious as face-to-face delivery but required 30% less clinician time. The fact that treatment is delivered by parents but is directed by the speech-language pathologist raises interesting issues about what constitutes dose.

Pharmacological dosage concepts: how useful are they for educators and speech-language pathologists?

The first part of this response to Baker (2012) examines studies that have attempted to determine the optimum treatment intensity of reading interventions associated with a Response to Intervention (RTI) model of service delivery. In general, the findings indicated that differences in broad measures of intensity (duration and scheduling) did not result in differences in reading outcomes. These non-significant findings and Baker's excellent discussion of all of the factors that impact treatment outcomes led me to question how useful pharmacological dosage concepts are for educators and speech-language pathologists (SLPs). This commentary concludes by acknowledging that the more information available about the active ingredients of treatment episodes, the better able one will be to design effective and efficient interventions to improve speech, language, and literacy.

A motor learning perspective for optimizing intervention intensity

Baker (2012) has addressed the critical issue of optimizing intervention intensity in the field of speech-language pathology. While this provides a useful framework from which to examine treatment intensities across a variety of approaches, it does little to inform how certain factors (e.g., feedback frequency, practice schedules) might be manipulated to optimize learning in ways that are effective and efficient. Evidence from the speech and non-speech motor learning literature suggests that the optimal intensities for utilizing practice and feedback are dependent on interactive factors such as task variability, target complexity, and therapeutic goals. In light of the complex interactions of treatment factors, it is proposed that the principles of motor learning be used as a guide to develop precise, interactive models that describe the optimal treatment conditions for specific approaches to intervention in speech-language pathology.

Optimal intervention intensity for emergent literacy: what we know and need to learn

In response to Baker (2012) unpacking critical components of optimal intervention intensity, this article explores what is currently known regarding intervention intensity for emergent literacy for children at risk for delays in this area of development. Studies specifically addressing intervention intensity related to phonological awareness and print knowledge suggest that more intensity does not always yield better results, and other factors suggested by Baker may influence the impact of intensity on children's outcomes. However, none of the research to date includes speech-language pathologists or children with diagnosed language disorders in the intervention models. Future research involving large-scale, systematic focus on intervention intensity in emergent literacy for children at risk for future reading disorders is needed to fully understand this construct within speech-language pathology services.

Paediatric speech-language pathology service delivery: an exploratory survey of Australian parents

Consideration of client values and preferences for service delivery is integral to engaging with the evidence-based practice triangle (E(3)BP), but as yet such preferences are under-researched. This exploratory study canvassed paediatric speech-language pathology services around Australia through an online survey of parents and compared reported service delivery to preferences, satisfaction, and external research evidence on recommended service delivery. Respondents were 154 parents with 192 children, living across a range of Australian locations and socio-economic status areas. Children had a range of speech and language disorders. A quarter of children waited over 6 months to receive initial assessment. Reported session type, frequency, and length were incongruent with both research recommendations and parents' wishes. Sixty per cent of parents were happy or very happy with their experiences, while 27% were unhappy. Qualitative responses revealed concerns such as; a lack of available, frequent, or local services, long waiting times, cut-off ages for eligibility, discharge processes, and an inability to afford private services. These findings challenge the profession to actively engage with E(3)BP including; being cognisant of evidence-based service delivery literature, keeping clients informed of service delivery policies, individualizing services, and exploring alternative service delivery methods.

A new era in speech-language pathology practice: innovation and diversification

A new era in speech-language pathology practice is pending, and one that impels us to innovate and diversify as we move forward into the 21(st) century. The impetus for this transformation will include the increasing cost and demand for healthcare services as the population ages, changes in Australian society, rapid developments in technology, and major advances in neuroscience. New models of service delivery will need to be considered in line with evidence-based treatment protocols, the concept of a continuum of care for chronic disorders, and the need to engage clients in self-management. Innovations in technology will provide the means by which these new models of service delivery might be achieved. The exponential increase in electronic therapy resources and devices will transform the therapeutic process and provide clinicians with engaging and flexible therapy options. Clinicians will be challenged by this paradigm shift in service delivery, and their long-held perceptions of their clients' capacity to respond to these changes. Other challenges will include the preparation of future speech-language pathologists, reimbursement for services, availability of appropriate technology, and widespread connectivity. The future of the profession is an exciting one as we move forward into an era of unprecedented change.

A family-centred model of care in paediatric speech-language pathology

Developments in paediatric models of care support family-centred practice (FCP); however, there is limited evidence for its use in speech-language pathology. This randomized controlled study examined whether parent satisfaction with FCP (n = 10) was greater than with usual practice (UP; n = 10) over 14 weeks for children with mild-moderate speech and/or language disorders. The FCP included parental goal decision-making; greater parent responsibility for clinic therapy tasks; and two home visits. There was a non-significant trend for the FCP group to have a higher mean score for the "Providing specific information" scale of the Measures of Process of Care. Goals for the FCP and UP groups were respectively targeted towards the Activities and Participation or the Body Function components of the International Classification of Functioning, Disability and Health-Children and Youth. While there were no significant differences between groups for speech/language outcomes post-intervention; it is clinically interesting that more children in the FCP group improved on the Renfrew Action Picture Test than the UP group. This study did not demonstrate a significant benefit for FCP over a relatively short timeframe in a small sample of children. Further research is warranted to determine if there is evidence for the use of FCP in speech-language pathology.

The birth and growth of a scientific journal

Clinical Linguistics & Phonetics (CLP) and its namesake field have accomplished a great deal in the last quarter of a century. The success of the journal parallels the growth and vitality of the field it represents. The markers of journal achievement are several, including increased number of journal pages published annually; greater diversity of topics related to the core mission of the journal; expanding cross-language coverage; and healthy interactions among editors, reviewers and contributors; and - for better or worse - journal impact factors. A journal is in a competitive dynamic with other journals that share its general domain of scholarship, which is a major reason why an apparent imbalance may emerge in the topic content of any particular journal. The content of a journal is determined by the nature and number of submitted manuscripts. As far as linguistic content goes, CLP's centre of gravity appears to have been mostly in phonology and phonetics, but certainly not to the exclusion of syntax, semantics and pragmatics. The clinical scope is broad, both in terms of concepts and types of disorder. CLP has secured its place among journals in the field, and it is an outlet of choice for many researchers throughout the world.

Advancing description and explanation in clinical linguistics: a legacy of Martin J. Ball

This article asserts the importance of explication of order and disorder in language as a privileged objective of clinical linguistics and service delivery and reviews the contributions of Martin Ball in advancing this agenda.

Clinical linguistics: its past, present and future

Historiography is a growing area of research within the discipline of linguistics, but so far the subfield of clinical linguistics has received virtually no systematic attention. This article attempts to rectify this by tracing the development of the discipline from its pre-scientific days up to the present time. As part of this, I include the results of a survey of articles published in Clinical Linguistics & Phonetics between 1987 and 2008 which shows, for example, a consistent primary focus on phonetics and phonology at the expense of grammar, semantics and pragmatics. I also trace the gradual broadening of the discipline from its roots in structural linguistics to its current reciprocal relationship with speech and language pathology and a range of other academic disciplines. Finally, I consider the scope of clinical linguistic research in 2011 and assess how the discipline seems likely develop in the future.