JCPSLP Vol 18 No. 1Mar 2016

Prediction and Prognosis

Are patient expectations and treatment credibility related to outcomes from LSVT ® LOUD? Alexandra Callins, Annie Hill, and Deborah Theodoros

Research in the fields of psychotherapy and rehabilitation has established an association between ratings of treatment credibility and patient expectations, and treatment outcomes. However, little is known about the relationship between credibility and expectation and the outcomes of speech- language pathology treatments. This study aimed to examine the associations between treatment credibility and patient expectations and the outcomes for people with Parkingson’s disease undergoing LSVT ® LOUD for hypokinetic dysarthria. The study also sought to explore the influence of participant variables on treatment credibility and patient expectations. Forty-nine participants completed a credibility and expectancy questionnaire prior to treatment. The treatment outcome measures included the mean change pre- to post-treatment on the total score of the Dysarthria Impact Profile and vocal sound pressure level during a monologue task. Correlation statistics revealed only one fair correlation between treatment credibility and the Dysarthria Impact Profile total score change. The findings support LSVT ® LOUD as an efficacious treatment for participants with hypokinetic dysarthria as substantial improvements were made to their speech, regardless of their perceptions of treatment credibility, expectations, and other participant factors. P arkinson’s disease (PD) is a neurodegenerative disorder, characterised by resting tremor, rigidity, bradykinesia, gait disturbance, and postural instability (Olanow & Tatton, 1999). During the progression of PD, hypokinetic dysarthria develops in up to 90% of people (Duffy, 2005). The speech disorder is characterised primarily by reduced volume, monotonous pitch and loudness, a harsh and breathy vocal quality, imprecise articulation, and, in some cases, disordered speech

rate (Duffy). The communication changes that present in PD may directly impact upon social skills and cause apprehension and embarrassment for people with PD during social interactions (Miller, Noble, Jones, & Burn, 2006). Furthermore, communication deficits can place limitations on participation in the family and society in general and may impact upon an individual’s self-concept (Miller et al., 2006). The Lee Silverman Voice Treatment (LSVT ® LOUD) is an evidence-based treatment for hypokinetic dysarthria associated with idiopathic PD (Fox, Ebersbach, Ramig, & Sapir, 2012). Information on the efficacy of LSVT ® LOUD has been published extensively (Atkinson-Clement, Sadat & Pinto, 2015; Ramig, Countryman, Thompson, & Horii, 1995; Ramig, Sapir, Countryman, et al., 2001; Ramig, Sapir, Fox, & Countryman, 2001; Wight & Miller, 2015). This program targets increased vocal loudness, increased effort, sensory calibration of loudness and effort, and self-cueing in order to improve speech intelligibility and maintain improvements long-term (Fox et al., 2012). This intensive program was developed around some of the principles that promote activity-dependent neuroplasticity, such as specificity, intensity, repetition, and saliency of treatment tasks (Fox et al.). Enhanced speech intelligibility can be expected due to increased loudness, increased effort across the speech mechanism, resulting in greater orofacial movements, tongue strength and mobility, and more precise articulation (Ward, Theodoros, Murdoch, & Silburn, 2000). Improvements in facial expression have also been noted by Spielman, Borod, and Ramig (2003) and some components of the oral and pharyngeal phases of swallowing were observed by El Sharkawi et al. (2002). It has been postulated that during some types of rehabilitation, such as psychotherapy, a person’s response to a treatment may be influenced by his or her expectations and belief about the credibility of the treatment (Smeets et al., 2008). Outcome expectancy is a person’s expectation for a successful rehabilitation outcome, assuming he or she makes the required effort (Geelen & Soons, 1996). It has been suggested that most psychotherapies are inextricably associated with the manipulation and adjustment of patient expectations (Greenberg, Constantino, & Bruce, 2006). The concept of treatment credibility is also important in the rehabilitation process. Treatment credibility refers to how believable, convincing, and logical the treatment seems to the patient (Smeets et al., 2008). The association between patient expectations and credibility and their treatment outcomes has been

Keywords credibility, expectation LSVT®LOUD Parkinson’s

disease speech-

language pathology

Thisarticle has been peer- reviewed

Alexandra Callins (top), Annie Hill (centre), and Deborah Theodoros

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JCPSLP Volume 18, Number 1 2016

www.speechpathologyaustralia.org.au