Results Summary

What was the research about?

Strokes occur when blood supply to the brain is blocked. A common result of stroke is weakness in one arm. One way to treat this weakness is constraint-induced movement therapy, or CIMT. In CIMT, patients work with a physical therapist, usually in person for 30 hours or more for a week.

In this study, the research team compared four ways to treat arm weakness due to stroke, including options for patients to do more at home:

  • In-person CIMT included 35 hours of clinic CIMT, focused on practicing movement and on increasing use of the weaker arm for day-to-day tasks. Therapists helped patients set goals for arm movement and track use of their weaker arm.
  • In-person CIMT with gaming included five hours of clinic CIMT, focused on increasing use of the weaker arm. For movement practice, therapists prescribed a video game for 15 hours over three weeks.
  • Video chat CIMT with gaming included five hours of clinic CIMT plus short video calls between clinic visits. Therapists prescribed a video game for 15 hours over three weeks.
  • Standard care included five hours of traditional movement practice in a clinic. Therapists asked patients to do strengthening exercises at home.

The research team looked at daily arm use and arm control and speed right after treatment and again six months later.

What were the results?

All types of CIMT improved daily arm use more than standard care right after treatment. In-person CIMT had the greatest improvement. Overall, patients maintained about 61 percent of the improvement in arm use six months later. Types of CIMT with the most therapist contact—in-person CIMT and video chat CIMT with gaming—maintained the most improvement in arm use.

In-person CIMT and video chat CIMT with gaming improved arm control and speed more than standard care right after treatment but not six months later.

Who was in the study?

The study included 193 patients with arm weakness due to stroke. The patients were receiving care at five clinics in four states. The average age was 59, and 64 percent were men. Patients’ strokes happened, on average, 4.5 years earlier.

What did the research team do?

The research team assigned patients by chance to one of the four groups. The team assessed daily use and control and speed of the weakened arm before treatment, after treatment, and six months later.

Stroke survivors, their family members, and therapists helped design the study and interpret study results.

What were the limits of the study?

Many patients didn’t use the video game for the full 15 hours, which may have decreased how well gaming worked. Also, the research team couldn’t assess 42 percent of patients at six months. Results may have differed if the team had had complete data.

Future research could explore ways to maintain improvements in arm use after CIMT and to encourage patients to follow home rehabilitation programs.

How can people use the results?

Doctors and patients can use the results when considering ways to treat arm weakness due to stroke.

Final Research Report

View this project's final research report.

Peer-Review Summary

Peer review of PCORI-funded research helps make sure the report presents complete, balanced, and useful information about the research. It also assesses how the project addressed PCORI’s Methodology Standards. During peer review, experts read a draft report of the research and provide comments about the report. These experts may include a scientist focused on the research topic, a specialist in research methods, a patient or caregiver, and a healthcare professional. These reviewers cannot have conflicts of interest with the study.

The peer reviewers point out where the draft report may need revision. For example, they may suggest ways to improve descriptions of the conduct of the study or to clarify the connection between results and conclusions. Sometimes, awardees revise their draft reports twice or more to address all of the reviewers’ comments. 

Peer reviewers commented and the researchers made changes or provided responses. Those comments and responses included the following:

  • The reviewers requested additional background information in the report, particularly about how gaming and virtual reality methods have affected medical care. The researchers expanded the introduction in the report but said that they did not expand on gaming and virtual reality methods much because they felt this would distract from the focus of the report. The researchers explained that the goal of the study was to affect access barriers in the delivery of constraint-induced movement therapy (CIMT), and the gaming technology they used was meant to be a vehicle for testing their efforts to improve access.
  • The reviewers asked whether the sizeable number of individuals who consented to participate in the study but did not start treatment were included in the analyses. The researchers said that in fact, they did not analyze data from the people who never started treatment because almost no data were collected about them. If they were to interpolate the data as necessary to include these individuals, the researchers felt that the results were more likely to be biased. The researchers noted that many of the patients that withdrew so early from the study did so because of challenges like transportation rather than because of the treatment they had been assigned, and the researchers felt that it would be appropriate to exclude those cases.
  • Reviewers suggested the study did not have enough statistical power to accurately assess differences among the four treatment arms and that the study should have been stopped or more subjects should have been recruited. The researchers said budget and time constraints did not allow for enrolling more participants to account for the higher-than-expected attrition, but the researchers did work to increase recruitment, for example by adding a study site. The researchers noted that they openly discussed their failure to achieve the desired sample size in the report and qualified their conclusions accordingly. The researchers said they still detected statistically significant comparative treatment effects despite the smaller than expected number of participants.
  • One reviewer felt the researchers overstated the known value of CIMT as an approach to stroke rehabilitation and stated that the researchers did not consider past literature demonstrating that CIMT was as effective as standard care for motor rehabilitation after stroke. This reviewer questioned whether the study conclusions were appropriate given the lack of sufficient power to test the primary outcome and comparable changes in motor improvement across all conditions. The researchers refuted the reviewer’s statement regarding lack of efficacy in CIMT, providing additional literature that demonstrated the superiority of CIMT over standard care. The researchers acknowledged that the results did not differ based on CIMT delivery methods. However, the researchers noted that their advisory board found the results to be encouraging because the findings show that engaging in rehabilitation of any type even long after a stroke leads to improvements in motor function and gives patients a choice of treatments administered remotely when it may not be feasible for them to obtain treatments in a clinic.

Conflict of Interest Disclosures

Project Information

Deborah Larsen, PhD, FAPTA, FASAHP^
The Ohio State University
Comparative Effectiveness of a Virtual Reality Platform for Neurorehabilitation of Hemiparesis

Key Dates

April 2015
November 2020

Study Registration Information

^Lynne Vonda Gauthier, PhD, was the original principal investigator on this project.


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Last updated: January 25, 2023