App Measuring Fall Risk for Adults Who Use Wheelchairs Yields High Usability

A smartphone app that assesses fall risk for adults who use wheelchairs had high usability, according to a study published in JMIR Formative Research.

The mobile health (mHealth) app, Steady-Wheels, provided users with an easy-to-use remote fall risk assessment tool.

“Previous literature has demonstrated that falls are common for individuals who use wheeled devices and are detrimental,” the study authors wrote. “The development of an objective, remote fall risk assessment tool could allow for accessible fall risk screening.”

The authors noted that the app’s guided navigation, large text and buttons, clear and concise instructions, representative illustrations, and simple error recovery all contributed to its high rates of usability.

Fall risk was determined by 12 demographic questions answered by users and 3 seat balance tasks that progressively got more challenging. Users were notified of their intuitive fall risk or STEADY score via a number ranging between 0 and 100 on a color-coordinated continuum, as well as a clear statement saying the user has high, medium, or low fall risk.

To determine the mHealth app’s usability, the authors conducted 2 rounds of testing with 5 participants who use wheelchairs in each round.

The mean (SD) age was similar in each round, at 59 (12.2) years in the first round and 58 (13.1) years in the second round. Round 1 included 3 men and 2 women, while round 2 included 2 men and 3 women, and all participants reported high levels of smartphone usage. Participants in both rounds had a mean time of 25 years using a mobility device.

Six of 10 total participants reported a powered wheelchair as their primary mobility device, followed by 3 using a scooter and 1 using a manual wheelchair.

Reasons for mobility device use included multiple sclerosis, paraplegia or quadriplegia, and stroke. Three participants experienced at least 1 fall in the past year, and all 10 had a self-reported fear of falling.

In the study, participants completed the questionnaire and seat balance tasks. After, they participated in semistructured interviews and completed the Systematic Usability Scale. All testing sessions were recorded and transcribed, and codes were identified in the transcripts to establish themes. Each round of testing resulted in calculated Average Systematic Usability Scale scores.

After the first round of testing, the authors calculated a mean (SD) Systematic Usability Scale score of 84.5 (11.4), indicating “excellent” usability according to the authors, with Systematic Usability Scale scores ranging between 72.5 and 97.5.

The authors also found 2 main themes after the first round of testing: ease of use and flexibility of design.

Regarding ease of use, some participants found the app easy to use while others had difficulty determining what order to complete the modules in. Some participants also suggested having larger text and multiple-choice buttons within the mHealth app, and to have the illustrations be more refined to better show users how to complete each task.

Many participants also said the limited answer options in the demographic questionnaire led to difficulty answering and made them feel the app was not tailored to them. For example, participants were asked to rate their level of concern with reaching higher objects or pushing their wheelchair, but said they ask someone else to grab the object for them or don’t push their wheelchair themselves.

Modifications were made based on this feedback prior to the second round of testing, which resulted in a higher mean (SD) Systematic Usability Scale score of 91.9 (4.3), indicating “best imaginable” usability, with scores ranging between 87.5 and 97.5. While the maximum Systematic Usability Scale score was the same in both rounds, the minimum score improved by 15 points.

Two new themes were identified in the second round: app layout and clarity of instruction.

While a completely different set of participants were included in the second round, they said the app was straightforward and user friendly and instructions were mostly clear. The only instructions that received criticism from users were the written ones for the functional stability boundary test.

“Future apps developed for fall risk reporting for this population should consider leveraging the insights identified here to maximize usability,” the authors concluded.

Reference

Frechette M, Fanning J, Hsieh K, Rice L, Sosnoff J. The usability of a smartphone-based fall risk assessment app for adult wheelchair users: observational study. JMIR Form Res. 2022;6(9):e32453. doi:10.2196/32453