## 2 Materials and Methods  
### Participant Recruitment  
This study was conducted at the inpatient rehabilitation facility (IRF), Froedtert Bluemound Rehabilitation Hospital, Milwaukee, Wisconsin, USA, from 2022 to 2024. All procedures received institutional approval from Medical College of Wisconsin (PRO-42316) and Marquette University (Reliance 21-082, HR-4044) in accordance with the Declaration of Helsinki. This study was conducted in accordance with the Declaration of Helsinki and approved by the Institutional Review Board of Medical College of Wisconsin(PRO-42316, approved 16 December 2021) and Marquette University (Reliance 21-082, HR-4044, approved 3 December 2021) for studies involving humans.  
Medical charts from 149 admitted stroke survivors were screened for study eligibility by a member of the research team (Figure 1). Inclusion criteria included unilateral stroke within the last 30 days, age \(\geq\) 18 years old, and English language speaking. Exclusion criteria included inability to give informed consent or follow two-stage instructions, severe cognitive impairment indicated by a score \(\leq\)9 on the Montreal Cognitive Assessment (MoCA), or concurrent illness or injury limiting the capacity to conform to study requirements. Of the participants screened using electronic health records, 77 were eligible for the study. Eligibility and intent to approach for consent was then acknowledged with the patient's attending physician. Of those eligible, 58 participants were approached by a study team member to describe the study along with its potential risks, whereas the remaining 19 were discharged home or to an outside facility. For those who expressed interest, a study team member administered the MoCA to confirm cognitive eligibility prior to conducting informed consent. The 42 participants who expressed interest all satisfied the cognitive screening criteria and provided written, informed consent to participate in this study. All participants were recruited within an 8-month period for an overall recruitment rate (number of participants consented/months recruiting) of 5.25 participants/month.  
After consenting, a total of 30 participants (12 female) completed the study protocol, and 12 participants withdrew (attrition rate: 28.6%). Reasons for withdrawal included disliking the vibrotactile cues after initial demonstration with the device (4), disliking the cues after 1-2 days of use (5), transfer of care to outside facility (1), complex therapy schedule (1), and physician withdrawal (1). Midway through the study, our team recognized the large withdrawal rate due to participants disliking the sensation of the vibrotactile cues. We therefore implemented a protocol amendment that allowed us to provide potential participants with a demonstration of the devices prior to consenting. Once implemented, no participants withdrew from the study due to disliking the cues.  
Figure 1: The study recruitment process illustrated, beginning with initial screening of potential participants and followed by eligibility assessment. Of the 77 eligible participants, 58 were approached, and 42 consented to participate in the study. A total of 30 participants completed the inpatient phase of the study.