Usability, Acceptability, User Experience, Human-Device Interaction, and Ergonomics in Two Mobile FES-Cycling Systems for Individuals with Spinal Cord Injury

This database originates from a study comparing two FES-cycling systems: the commercial BerkelBike Pro and a recumbent FES-bike prototype developed by the team at Politecnico di Milano. The aim of the study was to evaluate and compare the usability, acceptability, user experience, human-device interaction, and ergonomics of these two devices for individuals with spinal cord injury (SCI).

The study involved 15 participants with SCI, covering a wide range of ages (18 to 65 years) and injury types (both complete and incomplete, at acute and chronic phases). Each participant underwent three sessions with both FES-cycling devices:

First session: Dedicated to setting up the system for each participant. For both the BerkelBike Pro and the FES-bike prototype, the system settings were tailored to meet individual needs, ensuring optimal comfort and function.

Second and third sessions: Focused on actual training, where participants used the devices to engage in cycling activities.

At the end of the third session, participants completed a series of questionnaires to assess the usability, acceptability, user experience, and ergonomics of both devices. These questionnaires form the core of the study’s data collection and are central to understanding participants' interactions with the FES-cycling systems.

The database is organized as follows:

Demographic data: The first page contains demographic information, including participants' age, gender, height, weight, time after injury, injury type (ASIA grade), and injury level.

PGWBI scores: The second page includes baseline data collected using the Psychological General Well-Being Index (PGWBI), which assesses the participants' emotional and psychological state before engaging with the devices. The PGWBI consists of 22 questions grouped into 6 items: "anxiety", "depression", "positivity", "self-control", "health" and "vitality”. The responses are assessed on a 6-point scale ranging from 0 to 5. The score contributions for each question are then added together and transformed to achieve the final score that can range from 0 to 110.

SUS scores: The third page contains the results from the System Usability Scale (SUS), a standard 10-item questionnaire that evaluates the usability of each FES-cycling system based on user ratings. The SUS is evaluated using a 5-point Likert scale, where 1 corresponds to strongly disagree, while 5 to strongly agree. The score contributions for each question are then added together and multiplied by 2.5 to achieve the final score that can range from 0 to 100, where higher scores indicate better usability.

TAM-3 scores: The fourth page presents data from the Technology Acceptance Model 3 (TAM-3), which measures how participants perceive the ease of use and the usefulness of the devices. . The TAM-3 consists of 50 questions grouped into 14 items. These items include “perceived usefulness”, “perceived ease of use”, “self-efficacy”, “perception of external control”, “playfulness”, “anxiety”, “enjoyment”, “subjective norm”, “voluntariness”, “image”, “relevance”, “output quality”, “result demonstrability” and “behavioral intention”. The items are investigated using a 7-point Likert scale, where 1 corresponds to strongly disagree, while 7 to strongly agree.

UEQ scores: The fifth page includes responses from the User Experience Questionnaire (UEQ), evaluating participants' experience with the devices. The UEQ consists of 26 questions grouped in six items: “attractiveness”, “perspicuity”, “efficiency”, “dependability”, “stimulation” and “novelty”. Questions are scored using a 7-point Likert scale, where 1 corresponds to strongly disagree, while 7 to strongly agree. Then scores per item are transformed using a scale ranging from -3 to +3, with +3 representing the most positive value (extremely good) and -3 the most negative one (horribly bad). Values between -0.8 and 0.8 represent a neutral evaluation of the corresponding scale, values > 0.8 represent a positive evaluation and values < -0.8 represent a negative one.

Custom questionnaire scores: The sixth page contains data from a custom-designed questionnaire, created specifically for this study to assess the ergonomics of the two FES-cycling systems, with particular attention to human-device interaction at both the physical and psychological levels. It consists of 12 questions covering four items: the transfer from/to the bikes and the initial tuning, bike comfort, its accessibility, and the ease of interaction. Questions are evaluated using a 5-point Likert scale, where 1 corresponds to strongly disagree/very uncomfortable, while 5 to strongly agree/very comfortable.

This comprehensive data collection allows for a thorough comparison of the two FES-cycling systems in terms of user experience and overall acceptability in the SCI population.