An RCT of a Telemedicine Intervention for Hypokinetic Dysarthria in PD
Phase: NA
Conditions: Parkinson's Disease
Sponsor: VA Office of Research and Development

An RCT of a Telemedicine Intervention for Hypokinetic Dysarthria in PD 
 
 
 
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STUDY PROTOCOL 
 
 
Principal Investigator: David Sparrow 
 
Phone: 857-364-6407 
 
E-mail: david.sparrow@va.gov 
 
Protocol Date: 12/21/2020 
 
ClinicalTrials.gov number:  NCT04617496        
 
 

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1. Aims/Objectives 
 
 
The great majority of individuals with Parkinson’s disease (PD) develop speech impairments (Ho et al., 
1999; Miller et al., 2007; Schalling et al., 2017), most of which are grouped together and called hypokinetic 
dysarthria.  Hypokinetic dysarthria is typically characterized by altered prosody (e.g., reduced loudness and 
pitch variation), phonation (e.g., breathy or harsh voice), and articulation (e.g., imprecise consonants, 
centralized vowels) (Fox & Ramig, 1997; Ho et al., 1999; Hillenbrand & Houde, 1996).  Changes in speech 
may appear early in PD (Miller et al., 2008; Rusz et al., 2011; Skodda et al., 2013) and progress in severity 
over time (Skodda et al., 2013; Skodda et al., 2009; Skodda, Flasskamp, et al., 2011).  Further, such changes 
in speech lead to significant declines in functional communication and quality of life (Miller et al., 2006 & 2007). 
Pharmacological and surgical interventions that alleviate motor symptoms in PD are largely ineffective or 
sometimes even detrimental for speech (Ho et al., 2008; Schulz & Grant, 2000). We propose a pilot 
randomized, controlled trial (RCT) in patients with hypokinetic dysarthria in PD to assess the potential 
effectiveness of a home-based exercise intervention with interactive automated speech response features that 
encourage a higher level of speech performance. The overall goal of this project is to determine if this 
intervention leads to improved global speech function.  The results of this project will provide important 
information that can be used to design a definitive future trial. Our Specific Aims are: 
 
Primary Aim 
Specific Aim 1: To determine whether there is a difference in change in speech intelligibility (how well an 
individual is understood by others) between patients randomized to the intervention program vs. patients 
randomized to the health education control program. 
 
Hypothesis:  Patients in the intervention program will improve in speech intelligibility at 6 months, as 
compared with patients in the health education control program.  
 
Secondary Aim 
Specific Aim 2: To determine whether there is a difference in change in self-perceived communication ability 
(measured via the Communication Effectiveness Index) between patients randomized to the intervention 
program vs. patients randomized to a health education control program. 
 
Hypothesis:  Patients in the intervention program will improve in the Communication Effectiveness Index at 
6 months, as compared with patients in the health education control program. 
 
2. Background Information 
 
2.1 
Parkinson’s Disease in the VA Healthcare System 
 
The Veterans Health Administration (VHA) treats an estimated 80,000 veterans with Parkinson’s 
disease (PD) each year (VA Office of Research and Development, 2018). With the aging of the population, this 
number is expected to increase significantly in the next decade (Dorsey et al., 2007). The VA has 
demonstrated its strong commitment to providing the best possible care to all US veterans with PD by 
establishing six Parkinson’s Disease Research, Education and Clinical Centers (PADRECCs) around the 
country (Parkinson’s Disease Research, Education and Clinical Centers, 2018). These centers subsequently 
facilitated development of a collective to improve delivery of care across the VA healthcare system (the 
National VA Parkinson’s Disease Consortium). Even with this extensive network of neurologic specialists, 
many veterans still are unable to access care from this network due to disability or distance.  
 
The magnitude of the disability of PD and related burden is well known to the VA system.  Indeed, a 
comprehensive study of VHA databases found that compared to other chronic conditions, PD imposes a 
particularly heavy burden on veterans in the VHA healthcare system and their family (Gage et al., 2003).  
Relative to veterans with other chronic conditions, those with PD were more likely to report recent 
deteriorations in physical health, rely exclusively on the VHA for health care services, and ultimately to be 

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disabled. Of particular interest for the current proposal, veterans with PD were also much less likely to engage 
in regular exercise than veterans with other chronic conditions.   
 
2.2 
Clinical Manifestations of Parkinson’s Disease  
 
PD is a progressive neurodegenerative disorder, characterized by insidious onset. The first signs 
become clinically manifested when about 70 to 80% of the dopamine producing cells of the substantia nigra 
have degenerated (Booij et al., 2001). The cardinal clinical manifestations of PD include resting tremor, rigidity, 
bradykinesia, and postural instability/gait disturbance (Olanow et al., 2009). While levodopa is quite effective at 
treating cardinal manifestations of PD, its effects on speech and voice are limited and variable (Ho et al., 2008; 
Schulz & Grant, 2000).  
 
2.3 
Hypokinetic Dysarthria in Parkinson’s Disease  
 
Nearly 90% of individuals with PD develop speech impairments (Ho et al., 1999; Miller et al., 2007; 
Schalling et al., 2017), most of which are grouped together and called hypokinetic dysarthria.  Hypokinetic 
dysarthria is typically characterized by altered prosody (e.g., reduced loudness and pitch variation), phonation 
(e.g., breathy or harsh voice), and articulation (e.g., imprecise consonants, centralized vowels) (Fox & Ramig, 
1997; Ho et al., 1999; Hillenbrand & Houde, 1996).  Changes in speech may appear early in PD (Miller et al., 
2008; Rusz et al., 2011; Skodda et al., 2013) and progress in severity over time (Skodda et al., 2013; Skodda 
et al., 2009; Skodda, Flasskamp, et al., 2011).  For example, imprecise vowel articulation has been shown to 
be present even in mild stages of PD (Skodda, Visser, et al., 2011) and is a determinant of reduced speech 
intelligibility (Neel, 2008; Bradlow et al., 1996).  Research indicates that such changes in speech lead to 
significant declines in functional communication (Miller et al., 2006 & 2007).  
 
2.4 
Speech Treatment in Parkinson’s Disease 
 
Pharmacological and surgical interventions that alleviate motor symptoms in PD are largely ineffective 
or sometimes even detrimental for speech function (Pinto et al., 2004; Ho et al., 2008; Schulz & Grant, 2000; 
Tripoliti et al., 2014). Given the lack of benefit of these medical interventions, behavioral interventions have 
become the core methods for speech rehabilitation, especially those that facilitate attention to effort, self-
monitoring of vocal output, and generalization of treatment effects into improved ability to communicate 
effectively in daily life (Donovan et al., 2008; Dykstra et al., 2015; Atkinson-Clement et al., 2015).  
 
Behavioral treatments for speech have demonstrated increases in several overall loudness and other 
voice characteristics (Atkinson-Clement et al., 2015; Broadfoot et al., 2019; Ramig et al., 2018). However, 
studies of speech intelligibility, an important determinant of communication effectiveness, have some 
limitations. Observational studies reporting ratings of intelligibility before and after Lee Silverman Voice 
Treatment (LSVT) by patients and their families with the use of visual analog or ordinal scales have produced 
equivocal results (Ramig et al., 1994; Ramig et al., 1995; El Sharkawi et al., 2002; Ramig et al., 2004). Further, 
the subjective ratings used in these uncontrolled studies suffer from measurement bias because the patients 
and their families were invested in the treatment and were not blinded to pre- and post-treatment conditions 
(Rosenthal, 1966; Cannito et al., 2012). Two additional stimulus-based, objective scaling studies have been 
reported but one focused on intelligibility in terms of sounds or isolated words rather than sentences (sentence 
intelligibility) (Sapir et al., 2007) and the other was limited to the study of a comfortable loudness condition 
(Ramig et al., 1994) rather than a more natural condition where ambient noise is typically present. 
 
LSVT has become well established as a behavioral treatment modality for voice and speech in PD, 
requiring intense daily therapy for 4 weeks (Trail et al., 2005; Ramig et al., 2018). The high intensity and 
required consistency that makes this program successful is also associated with a tendency for patients to 
decline starting therapy or to miss therapy appointments (Sackley et al., 2018; Covert et al., 2018), likely 
mediated by distance from a center providing specialized speech training or the limited functional mobility that 
characterizes PD (Fox et al., 2012; Theodoros et al., 2016). The opportunity for a person with PD to receive 
speech treatment within his or her own home may alleviate issues with patient access.  

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To optimize behavioral interventions such as LSVT, it would seem important to ascertain PD patients’ 
experiences with these interventions. Yorkston and colleagues conducted face-to-face, semistructured 
interviews with patients who reported that PD interfered with everyday communication (Yorkston et al., 2017a; 
Yorkston, et al., 2017b). Although many patients reported positive experiences with speech treatment, some 
reported dissatisfaction with speech drills, describing them as repetitive, irrelevant, and even boring. Based on 
these negative impressions as well as the motor and mobility impairments that characterize PD, the authors 
suggest one strategy for enhancing engagement and relevance is to integrate speech activities into a physical 
exercise program (Yorkston et al., 2017a). In this context, exercise training has the added benefit of improving 
parkinsonian motor signs (Corcos et al., 2013; Kelly et al., 2014). 
 
2.5 
Limitations of Speech Treatment in Parkinson’s Disease  
 
Behavioral treatments to improve speech tend to require intense efforts (LSVT [Ramig et al., 2018], 
SPEAK OUT! [Behrman et al., 2020], respiratory effort treatment [Ramig et al., 1995]). For example, LSVT 
involves intensive respiratory/phonatory training during 16 sessions per month. Despite the evidence for the 
effectiveness of LSVT, the intensive nature of therapy can be a concern for both clinicians and patients 
(Sackley et al., 2018; Theodoros et al., 2016; Covert et al., 2018; Miller et al., 2011), particularly within the 
context of increasingly stretched clinical resources (Theodoros et al., 2016; Miller et al., 2011). Therefore, it’s 
not surprising that clinicians may not always follow the LSVT prescribed form or intensity (Miller et al., 2011; 
Covert et al., 2018).  Clearly, the level of clinic attendance required for speech treatment can be demanding for 
the patient (Sackley et al, 2018); furthermore, the physical symptoms of PD and related mobility challenges 
can sometimes make participation extremely difficult (Theodoros et al., 2016; Fox et al., 2012). In addition, 
access to treatment can be limited for patients in rural areas. In the VA, approximately 34 to 36% of its 
enrollees live in rural areas (National Center for Veterans Analysis and Statistics, 2016; West et al., 2010). 
Veterans geographically removed from medical centers can only access limited VA service networks that could 
address their speech impairment and improve their ability to maintain independent functioning (Doyle & 
Streeter, 2017; Covert et al., 2018).   
 
2.6 
Speech Treatment in the Home  
 
The availability of speech treatment such as LSVT remains limited because of distance to a treatment 
facility and availability of certified clinicians (Theodoros et al., 2016; Miller et al., 2011). Moreover, sustained 
delivery of speech treatment can be difficult, often resulting in short treatment periods without follow-up 
episodes of care (Miller et al., 2011). A potential solution to these challenges is to capitalize on advances in 
technology-supported treatment delivery to the home (Theodoros et al., 2016). One such phone-based 
platform being used to deliver health behavior interventions is interactive voice response (IVR) (Tsoli et al., 
2018). IVR is very appealing given that patients simply use a telephone to participate in a given intervention, 
avoiding the need for patients to have previous computer experience or home internet access. Further, an IVR-
supported program requires fewer personnel and financial resources and gives patients the opportunity to 
participate in training over the long term in the home environment. 
 
3. Rationale and Purpose  
 
 
We propose to conduct an RCT in patients with hypokinetic dysarthria in PD to assess the potential 
effectiveness of a novel home-based intervention with interactive automated speech response features that 
encourage a higher level of speech performance. Pharmacological and surgical interventions have been 
shown to be largely ineffective or sometimes even detrimental with regard to speech outcomes (Pinto et al., 
2004; Ho et al., 2008; Schulz & Grant, 2000; Tripoliti et al., 2014). Behavioral therapy remains the primary 
treatment but tends to require intense and frequent face-to-face sessions at a health care facility making 
participation very difficult for patients who have mobility challenges or who live far from these facilities (Sackley 
et al., 2018; Theodoros et al., 2016; Covert et al., 2018; Miller et al., 2011).  Moreover, facility-based training 
programs may not lead to sustained speech practice beyond the period of supervised training. The proposed 

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intervention is home-based and combines speech and exercise training. The intervention involves a system 
programmed to continually challenge patients to improve their speech performance within a progressive 
framework where speech adjustments facilitate movement through the exercise regimen.  
  
The current proposal is consistent with the VA’s national priority of employing telehealth approaches to 
help increase access to needed health care (Darkins, 2014; Wilkinson et al., 2016). In addition, this proposal 
addresses an overall area of RR&D interest related to one of the most complex medical conditions increasing 
in prevalence in veterans, i.e., PD, which is characterized by multiple impairments including hypokinetic 
dysarthria.  
 
4. Relevance to Veterans Health 
 
 
Parkinson’s disease is the second most common neurodegenerative disorder, affecting over 80,000 
veterans treated within the VA Healthcare System. The great majority of these veterans have speech 
impairments that negatively impact their ability to communicate effectively in daily life. This study will test the 
hypothesis that a combined speech and exercise intervention will improve speech intelligibility in people with 
PD and speech impairment.  Remotely-delivered intervention programs have the potential to be accessed 
easily and conveniently by large numbers of people with PD. The findings of this study may help VA clinicians 
provide optimal care for the many veterans with PD and speech impairment.  
 
5. Study Design 
 
 
We will conduct a pilot RCT to evaluate the combined speech and exercise intervention program in 
patients with hypokinetic dysarthria in PD. One hundred four patients with PD will be randomly assigned (1:1) 
to the 6-month intervention program or the 6-month health education control program. All evaluations will take 
place at the Jamaica Plain campus of the VA Boston Healthcare System. 
 
5.1 
Intervention Program  
 
The program is designated the Telephone-Linked Computer-based Long-term Interactive Fitness 
Trainer (TLC-LIFT) (Sparrow et al., 2011).  TLC-LIFT uses IVR technology, including speech-recognition 
software, to communicate with a participant during each session. Over the course of each TLC-LIFT session, 
the system provides verbal prompts to which the participant must respond by speaking.   
 
To reduce the risk of an injury from exercising, participants are instructed in every session to stop 
exercising immediately if they experience symptoms suggestive of a musculoskeletal injury, significant 
respiratory symptoms, or any suspected cardiac issues.   In addition, participants are instructed to contact 
research staff if they are hospitalized for any reason.  VA electronic medical records are reviewed at least once 
per month for potential adverse events.  Participants are called when they miss sessions for 1 week to 
determine the reason for missing sessions (e.g., adverse event, vacation, etc.).  
 
All exercise equipment will be shipped to participants’ homes at enrollment and will be picked up by 
carrier service after the 6-month follow-up evaluation. 
 
Adherence to this intervention will be encouraged by intermittent newsletters, birthday cards, holiday 
greeting cards, and certificates of study participation. Participants will earn certificates of achievement, which 
will be mailed after completion of blocks of 12 sessions (approximately monthly if fully adherent).    
 
5.2 
Health Education Control 
 
The group randomized to receive health education will serve as an attention control.  The health 
education control system is designed to deliver general information 3 times per week via auditory content 
about a variety of health topics including content on exercise and speech enhancement.  Participants are 
provided with illustrations (e.g., types of exercises important for persons with PD) with written instructions to 
accompany the auditory content.  In addition, participants select a topic from 4 content areas: common 
symptoms, medical conditions, preventive medicine topics, and tips for healthy living with PD.  These PD-

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specific tips include recommendations to promote effective communication, mobility strategies, such as 
strategies for moving from lying down to a sitting position, and from sitting to standing position, and tips to help 
with performance of daily activities including organization of the physical environment and reducing time 
pressure.  Control participants also receive an illustrated booklet demonstrating these strategies and tips.  
 
6. Study Subject Selection 
 
a. Sample Description 
 
 
We will recruit 104 patients using a protocol similar to what we are using in our ongoing project to 
reduce falls in veterans with PD (VA RR&D Merit Review; PI: Sparrow).  Specifically, this approach will involve 
searching the VA’s Corporate Data Warehouse (CDW) to identify patients with PD who potentially meet the 
eligibility criteria (see 6b & 6c). For patients identified this way, data from the medical records will be 
abstracted.  To assess electronic medical records, we will use the CAPRI System, which provides one 
interface into the VISTA systems within VISN 1. Patients with PD typically have an initial Neurology 
consultation and then are seen in Neurology Clinic every 6 months. A standardized VA note format is utilized 
which includes HPI, medications, and detailed neurologic examination at each visit. The initial VA Neurology 
consultation will be reviewed with as many subsequent clinic notes as needed to establish the diagnosis of PD 
and responsiveness to dopaminergic therapy. The two most recent Neurology Clinic notes will also be 
reviewed to determine current medication use and functional status. Pharmacy records will also be reviewed to 
confirm stability of medication dosage. Also, Primary Care provider notes and any hospital discharge 
summaries from the previous year will be reviewed for evidence of exclusionary conditions.   
 
b. Subject Inclusion Criteria 
 
 
Patients with PD who meet eligibility criteria will be recruited into this study.  Specific inclusion criteria 
will include a physician diagnosis of idiopathic PD; at least 2 of the 3 cardinal signs of PD (resting tremor, 
rigidity, bradykinesia); response to dopaminergic medication; absence of secondary causes of Parkinsonism; 
Hoehn and Yahr stage 2-3 disease; stable antiparkinsonian medication for at least 2 weeks; hypokinetic 
dysarthria; and an age of 40 years or older. 
 
c.  Subject Exclusion Criteria 
 
 
Specific exclusion criteria will include a Mini-Mental State examination score lower than 24; a Beck 
Depression Inventory-II > 24; previous laryngeal surgery; a diagnosis of angina pectoris (unless 
symptomatically resolved post-revascularization); a history of myocardial infarction (MI) within 6 months, or 
remote (>6 months) MI with current ischemia on exercise stress test; a history of ventricular dysrhythmia 
requiring current therapy, or current atrial fibrillation without adequate rate control (resting HR <90); 
participation in a regular exercise program (2 or more times weekly for 30 minutes or longer per session) 
during the previous 2 months; and presence of other conditions limiting the ability to participate or associated 
with poor short-term prognosis, for example, severe degenerative joint disease, stroke with severe residual 
deficits, severe peripheral neuropathy, severe psychiatric illness, advanced cancer, or renal failure on renal 
dialysis. 
 
 
7.  Data Collection 
 
7.1  
Speech Intelligibility 
 
Speech intelligibility has been described as the primary goal of dysarthria treatment (Miller, 2013; 
Cannito et al., 2012). In the proposed study, speech intelligibility will be measured as the percentage of words 

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understood from the acoustic recordings of participants.  Participants will be recorded while reading a random 
set of 11 sentences from the Assessment of Intelligibility in Dysarthric Speech Sentence Intelligibility Test (SIT) 
stimulus bank (Yorkston & Beukelman, 1980).  All recordings will be obtained with the use of a head-mounted 
condenser microphone. 
 
A group of native speakers of American English with no history of speech, language, or hearing 
disorders or experience rating speech will participate as listeners in an assessment of speech intelligibility. 
Listeners will be asked to transcribe a single sentence from each study participant’s recording. Amplitude-
normalized speech stimuli will be played over headphones. Listeners will be asked to orthographically 
transcribe each sentence to the best of their ability. Their transcriptions will be compared with the actual stimuli 
to calculate a percentage of intelligibility.  
 
7.2  
Communication Effectiveness Index 
 
Research indicates that the impact of hypokinetic dysarthria in PD goes beyond severity of speech 
impairment; it reduces the patient’s ability to effectively communicate in daily life (Miller et al., 2008; Miller et 
al., 2006; McNamara & Durso, 2003). In the proposed study, we will measure the Modified Communication 
Effectiveness Index (CETI-M), a comprehensive patient-reported outcome.  Specifically, participants will rate 
their communicative effectiveness in 10 different speaking situations (e.g., in noisy environments, over the 
phone) on a 10-point Likert scale, where 1 = not effective and 10 = extremely effective. 
 
 
8.  Statistical Analysis Plan 
 
Primary Aim 
Specific Aim 1: Our primary outcome will be the change in speech intelligibility at 6 months. Because each 
individual contributes up to two values, at baseline and at 6 months, PROC MIXED (SAS) will be used to 
estimate regression parameters based on a mixed-effects longitudinal model (Diggle et al., 1994) with the use 
of the REPEATED statement with an unstructured covariance matrix.   
 
 
Secondary Aim 
Specific Aim 2: We will perform univariate analyses based on the Mann-Whitney U test to compare the 
distribution of change in CETI-M scores from baseline to 6 months in the intervention vs. control group.  
 
8.1 
Power 
 
With the use of a randomized pre-post LSVT design in patients with hypokinetic dysarthria in PD, 
Cannito et al. (2012) observed an effect size of 0.75 for the outcome speech intelligibility treated as a 
continuous variable (our primary outcome). With a sample size of 39 participants per group, we will have 90% 
power (α=0.05) to detect this effect size.  
 
 
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