Table 3.

Feasibility factors.

Feasibility Factors	Findings
User (stroke survivors) recruitment	Eight stroke survivor users were evaluated for participation in the study. Five met the inclusion criteria and completed the study.
Retention for the planned duration of the treatment and testing time	All five enrolled users completed all treatment and testing sessions
User preparation and donning time of equipment	Equipment donning required an average of 15 min.
Reported comfort of the system	Users reported no discomfort regarding tDCS electrode placement or current intensity. Users reported no discomfort with the harness system or visual/auditory features of the VR.
Capability to wear and use the technologies.	All five users were able to wear the technologies and reported engagement in the presented motor tasks during tDCS and VR/treadmill training.
User endurance of the technologies for the planned treatment time	All five users demonstrated endurance for the length of each treatment session. We found it important to offer rest periods between walking practice trials on the treadmill and during phase two overground practice. Users performed a mean of 191.8 ± 32.8 (SD) obstacle-clearance steps per VR treadmill training session.
Technology flexibility in providing the incremental levels of difficulty needed for progressively more challenging motor learning stance phase practice	The technology offered numerous domains across which task difficulty could be progressed. These included treadmill speed, timing of the frequency of walking obstacles in the VR system, height of obstacles in the VR system, use of knee cage to protect joint structures during walking practice, ankle dorsi-flex assist to protect knee joint structures and assist with swing phase dorsiflexion, upper limb support, physical assist by the treating therapist, and verbal cues from the treating therapist. **
User’s ability to attempt the progression of planned challenges during stance phase motor learning	All five users showed capability to attempt task progression across one or more domains of task difficulty.
Ability to show progressive improvement in performing progressively more challenging aspects of the motor learning protocol using the technologies	All five users progressed across one or more domains of task difficulty (details provided below in the results for individual users).
Safety	All participants completed 10 training sessions with no adverse events. No users experienced a fall or near fall.

** Example of the flexible domain of treadmill training gait speeds and the recorded range from initial session to final treatment (m/s): S1: 0.18–0.24; S2: 0.38–0.38; S3: 0.2–0.35; S4: 0.20–0.16; S5: 0.14–0.28. These training speeds were separate from chosen gait speeds.