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What’s the aphasia treatment dosage gap, and how can Constant Therapy address it? What new research shows

Kate Ying | Aphasia

With at least 2,000,000 people currently living with aphasia in the United States alone, it is essential that patients can access the level and frequency of therapy and care that will maximize their potential treatment gains. What is that optimal level of care, however? In reality, how often do aphasia patients obtain it? And, just as important, what are the ramifications when they do not?

A recent study offers important insights into these questions. Specifically, researchers documented a notable gap between the amount (or “dosage”) of aphasia rehabilitation therapy found to be optimal in the literature versus the amount of treatment actually received by typical aphasia patients in practice. This post will summarize the key findings of the study and discuss how Constant Therapy can serve as a crucial bridge in the aphasia research–practice dosage gap. 

Study design and aims

The article, published in the September 2021 issue of the American Journal of Speech-Language Pathology, examined whether a disparity exists between the aphasia treatment dosage and intensity delivered in research trials as compared to standard outpatient practice. To do so, researchers employed a two-stage process. Data on the treatment dose in research settings was gathered via a review of the aphasia rehabilitation literature over the 10 years between 2009 and 2019. Meanwhile, data about treatment dosage and intensity in outpatient clinical practice was estimated from speech-language pathology billing information at the Center for Rehab Services (CRS) at the University of Pittsburgh Medical Center. Given CRS’s presence as a major regional rehabilitation provider with over 20 outpatient clinics, their data approximated the treatment dose received by average aphasia patients overall.

Based on that analysis, researchers sought answers to three central questions:

  1. What dose and intensity of aphasia treatment was beneficial according to research studies? 
  2. What dose and intensity of treatment do typical people with aphasia actually receive in outpatient rehab?
  3. Is there a notable gap between the dosage and intensity of therapy across those two settings? 

Main takeaway: a dosage gap does indeed exist in aphasia treatment

The key takeaway from this study is as seemingly straightforward as it is urgent to address. Namely, the review found that a marked research–practice dosage gap indeed exists in aphasia rehabilitation. Specifically, researchers revealed that the evidence-based treatment dosage for aphasia in research was a median of 20 total hours spread across 15 sessions conducted approximately 3 times per week. In sharp contrast, the median treatment dosage typically received by aphasia patients in outpatient clinical settings was only 7.5 hours of total treatment over the course of 10 sessions conducted 1 to 2 times per week. That amounted to a research–practice dosage gap of 12.5 total hours of aphasia intervention; put differently, the median treatment dosage deemed effective in research was over 2.5 times the median dosage actually received by patients in outpatient care. In short, the average aphasia patient is not getting nearly as much therapy as needed.

This finding has far-reaching implications for people living with aphasia, their caregivers, clinicians, and scientists. Aphasia can considerably impair communication and diminish quality of life, and aphasia rehabilitation aims to restore communication abilities to the greatest extent possible. The research–practice dosage gap stymies that objective by potentially catalyzing a decline in the efficacy of treatment interventions when transitioned from research settings to clinical practice (a “voltage drop”), thus hindering patient outcomes. As the researchers caution, “if an evidence-based treatment protocol provides an estimate of a treatment effect at one dose, it may not engender clinically significant changes at a lesser dose.”

Next steps: patients with aphasia need more therapy than they are getting

In order to reduce the research–practice dosage gap in aphasia rehabilitation, it is crucial that patients receive significantly higher levels of treatment than the realities of traditional in-office health care usually can provide. For one, many insurance policies strictly limit the number of covered speech therapy sessions, if indeed they offer such a benefit at all. Given that the out-of-pocket cost for speech therapy usually starts at (and frequently exceeds) $100 per session, significant financial burdens might restrict a patient’s access to an effective frequency of care via traditional outpatient practice alone. Moreover, even when cost is not a barrier to access, provider shortages often are. This is especially true for people who live in medically underserved areas and may have to travel great distances to reach a trained provider. 

Fortunately, advances in technology have made solutions for this problem possible where previously they did not exist. Constant Therapy is a convenient, engaging, and highly effective tool to bridge the dosage gap, thus answering the study’s call for “easily accessible materials to facilitate effective home practice and augment limited face-to-face time with clinicians.” In fact, the researchers pointedly assert that “software and app development”—a field Constant Therapy has pioneered since its founding—“constitute[s] an ideal method for delivering effective home practice.” 

This study also aligns with new research about the effect of self-managed speech-language therapy dosage on patient outcomes. That research, published in July 2022 by researchers at Boston University, similarly discovered that augmented dosage frequency with Constant Therapy was associated with better outcomes for people with language disorders. Because rigorous trials have proved the significant therapeutic benefit of Constant Therapy as a treatment for aphasia, patients do not sacrifice efficacy of care by incorporating the program into their rehabilitation regimen. On the contrary, supplementing outpatient SLP services with Constant Therapy offers a clear avenue by which patients can increase their treatment dose and intensity to match levels found effective in research studies, thereby minimizing the research–practice dosage gap and optimizing their aphasia recovery.

Read the Research

Cavanaugh, R., Kravetz, C., Jarold, L., Quique, Y., Turner, R., & Evans, W. S. (2021). Is There a Research–Practice Dosage Gap in Aphasia Rehabilitation? American Journal of Speech-Language Pathology, 30(5), 2115–2129.

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  1. sally jones-mcnamara, mcs, ccc-slp, ccp, cce, cds

    Excellent points!

    • Carla Gates

      Thank you!


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