Lee-Silverman Voice Treatment (LSVT LOUD®), SPEAK OUT!®, and Pitch Limiting Voice Treatment (PLVT) are three of the most well-regarded voice treatment approaches for patients who have Parkinson’s disease.

Two offer high-quality training while the other has an app. All are evidence-based and have a clear track record of helping patients who have Parkinson’s disease.

So which should you choose? While the right answer depends on each person, we put together a summary to help you decide.

In this article, you’ll learn how each approach works, the basic protocol, and details of how to become trained or certified. We also link to other helpful resources, including videos, websites, and journal articles.

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LSVT LOUD (Lee-Silverman Voice Treatment)

lsvt loud vs speak out

What’s The Goal?

The goal of LSVT LOUD is to train patients to speak louder. More specifically, to speak at a “normal” loudness level.

The treatment does this by helping patients recognize how loud or soft they sound to other people. The aim is a life-long ability to use a stronger voice through continued practice, even after treatment is done.

Some patients treated with LSVT LOUD also experience improved articulation and swallowing abilities.

This indicates that these related but untrained movements generalized—a sign of motor learning in action. Read more about motor learning: 9 Principles of Motor Learning for Speech-Language Pathologists.

How Does LSVT LOUD Work?

Three Key Strategies

  1. The only treatment target of LSVT LOUD is vocal loudness (amplitude)

  2. Intensive and high effort. Patients are encouraged to continually work harder.

  3. Sensory re-calibration. Through sensory feedback, patients learn to recognize that their louder, stronger voice sounds ‘normal.’ This increases the likelihood that they’ll use this louder voice outside of therapy—so that it becomes their normal voice.

Intensive Treatment Schedule

LSVT LOUD consists of 16 sessions. Over the course of 4 weeks, the therapist provides 1-hour sessions, four times per week.

Patients are given daily homework.

Basic LSVT LOUD Protocol

  1. The patient says “ah” in a loud voice (not shouting) for as long as they can

  2. The patient reads 10 functional phrases (things they say in everyday life) in a loud voice

  3. The patient says “ah” in a slightly high-pitched and loud voice for 3 seconds

  4. The patient says “ah” in a slightly low-pitched and loud voice for 3 seconds

  5. The patient reads aloud (increasingly complex material) in a loud voice for 5+ minutes

  6. The patient completes daily exercises once per day on therapy days and twice per day on off-therapy days

  7. The patient continues daily exercises after the program ends

Therapist Cueing

Cueing for LSVT LOUD is simple: Ask the patient to “do what I do” and model the appropriate loudness.

Prolonged or specific verbal instructions are not recommended. For example, don’t explain, “That wasn’t quite loud enough. You should tense your ab muscles and take a big breath from your stomach.”

Stick with “do what I do.”

LSVT LOUD Certification

You can become LSVT LOUD certified via an online course or a live course. The live courses are also virtual.

In-person courses are currently available in Europe and Japan.

1. Who Can Be Certified for LSVT LOUD?

Speech-language pathology professionals, assistants, and students.

2. How Much Does LSVT LOUD Certification Cost?

  • $605  Professionals
  • $465 Fellow/Resident
  • $325  Students
  • $225  Previously Certified Clinicians  

They also offer group discounts for groups of 5+.

3. What Comes With the LSVT LOUD Training?

  • 1.35 ASHA CEUs
  • LSVT LOUD Certification
  • Digital course materials (printed & shipped to you for an extra cost)
  • LSVT LOUD Clinician Account (treatment forms, marketing materials, bonus videos, webinars)
  • Your name listed on the LSVT Global Certified Clinician for referrals
  • LSVT LOUD Homework Helper video
  • Other LSVT LOUD Resources (pre-recorded lectures, video demonstrations, interactive case study presentations)
  • Access to LSVT LOUD Clinician Facebook group
  • Ongoing support from LSVT LOUD experts for clinical questions

4. How Long Does The LSVT LOUD Course Take?

13.5 hours.

LSVT LOUD Resources

LSVT LOUD Research Articles

Videos and Webinars

LSVT LOUD Speech Therapy for Parkinson disease


Free Grandson Observing His Grandfather Play the Guitar Stock Photo

SPEAK OUT! is a voice treatment approach developed by the Parkinson’s Voice Project.

What’s The Goal?

The goal of SPEAK OUT! is for people with Parkinson’s disease to produce a stronger, clearer voice.

This approach is based on the principles of motor learning and on the understanding that people with Parkinson’s disease have improved speech when they learn to speak with intent (versus using automatic motor behaviors).

Automatic speech is believed to be more impacted by Parkinson’s disease—hence the emphasis on intentional speech.

How Does It Work?

Before starting SPEAK OUT! treatment, patients and their caregivers attend a Learn About Parkinson’s webinar.

During treatment, a therapist guides the patient through a series of speech, voice, and cognitive exercises. These exercises strengthen the muscles used for speech and swallowing. Patients follow a workbook that’s provided to them.

Treatment consists of 8-12 speech therapy sessions. Sessions are typically 40 minutes long. Patients also are given homework to do twice per day.

In the 3rd or 4th week of treatment, the patient attends a speech or singing group led by a SPEAK OUT! Provider.

Once treatment is over, patients are followed up every 3-6 months.

The Parkinson’s Voice Project offers a lot of support to help patients during this process. These include daily SPEAK OUT! Home Practice Sessions, access to en eLibrary (for SPEAKOUT! workbook, flashcards, and songbooks), weekly Online Sing-Alongs, and even an annual concert called SING OUT!

What Does A SPEAK OUT! Session Look Like?

From and a 2016 study by Watts:

  1. Warm-up vocalizations

  2. Sustained vowel production

  3. Pitch glides

  4. Counting

  5. Reading (words, phrases, sentences, and paragraphs of gradually increasing length and complexity)

  6. Cognitive exercises (thinking + loudness. Patients often feel this is the most rewarding component)

  7. Discussion (‘How will you Speak with Intent today?’ Carryover, planning, and self-monitoring)

The LOUD Crowd

The Parkinson’s Voice Project created a follow-up program called The LOUD Crowd. It’s a weekly group led by a speech-language pathology professional where SPEAK OUT!® graduates can practice their exercises together.

SPEAK OUT! & LOUD Crowd Training

Parkinson’s Voice Project offers an online course to train Speech-Language Pathologists, assistants, and students.

It’s not a certification and doesn’t require renewal fees, unlike LSVT LOUD.

1. Who is SPEAK OUT! Training For?

Speech-language pathology professionals, assistants, and students.

2. Cost

$475 US
*Digital SPEAK OUT! Workbooks and flashcards included. Physical copies are available for an extra cost.

3. What Comes with SPEAK OUT! Training

  • 1.0 ASHA CEUs
  • Training to conduct a speech evaluation with stimulability testing
  • Training for SPEAK OUT! (individual therapy)
  • Training for The LOUD Crowd (group sessions)
  • Training for clinical documentation
  • Access to eLibrary (flashcards, workbooks in English, French, German, Hebrew, Italian, Japanese, and Spanish)
  • Other online clinical resources (sample treatment forms, training videos, marketing materials)
  • SPEAK OUT! Workbook for each U.S. patient with Parkinson’s
  • SPEAK OUT!Therapy Flashcards (photo, word, math, and conversation)
  • Membership in SPEAKOUT! Providers Facebook Group

*The course must be completed within 30 days of.

4. How Long Does SPEAK OUT! Training Take?

10 hours.

SPEAK OUT! Resources

SPEAK OUT! Research Articles

1. SPEAK OUT! Exercise Example. “Let’s Go to a Concert”:

PLVT (Pitch Limiting Voice Treatment)

Pitch Limiting Voice Treatment (PLVT) was developed by Bert de Swar, a speech therapist at Radboud University Medical Center. PLVT emphasizes speaking loud and low to increase vocal intensity without excessive pitch or hypertension of laryngeal muscles.

While PLVT has a training program, we were unable to find it offered in English. Even without the training, a useful takeaway is to emphasize a voice that is “loud and low” to increase voice intensity without hypertension.

The university sells an app called Voice Trainer (available in the App Store and Google Play) which gives immediate visual feedback about a patient’s loudness and pitch.

How The Voice Trainer App Works

First, adjust the settings for pitch and loudness based on your patient’s goals and norms.

Then measure the patient’s voice as they speak.

  • When their voice is loud enough, the dot on the screen is green
  • If it’s not loud enough, it’s red
  • If their pitch is correct, the dot is in the middle of the screen
  • If their pitch is too high (or low), the dot shows up high (or low) on the screen

The app can be used by patients speaking any language.

Learn more about the Voice Trainer app on Radboud University Medical Center’s website.

More Voice Resources

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  • American Speech-Language-Hearing Association. (n.d.). Dysarthria in adults [Practice portal]. Retrieved Sept 11, 2023.
  • De Swart, B. J. M., Willemse, S. C., Maassen, B. A. M., & Horstink, M. W. I. M. (2003). Improvement of voicing in patients with Parkinson’s disease by speech therapy. Neurology, 60(3), 498-500.
  • Voice Trainer. (n.d.) Radboud University Medical Center. Retrieved Sept 11, 2023, from
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