Step by step: Data4Life and Charité Universitätsmedizin Berlin

The design challenge in this project was: "Improve the engagement and retention of participants in a sensor-based study on stroke rehabilitation!"

After a stroke, it is difficult for many patients to regain their ability to move.

Patients need a lot of time and motivation to recover from a stroke. As a result of neurological deficits, they are often physically and cognitively limited, which can lead to restricted mobility. Our project partners Charité - Universitätsmedizin Berlin and Data4Life are conducting the “Sensor-S” study to investigate the extent to which mobile devices can support the rehabilitation process. In particular, the study is looking at whether sensors in combination with mobile devices can have a positive influence on the motivation to participate in rehabilitation. For example, stroke patients can track their progress in real time and receive regular feedback via the D4L Collect app. One of the hypotheses is that this in turn increases their motivation and participation and makes the rehabilitation program more effective overall.

In the associated experimental setup, it is important to minimize the burden on the study participants. This includes making the attachment of sensors to the feet and the technical set-up for data collection as practical as possible. These are precisely the challenges that Design Thinking students at our HPI d-school addressed in the summer semester of 2024.

Human-centered design can be the key to a successful study.

During the research phase, it became clear that, in addition to a change in lifestyle, patience in particular plays a crucial role in the success of rehabilitation. When recovering from a stroke, rapid progress is rare. Interviews with patients, their relatives and medical staff confirmed this assessment. Furthermore, the Design Thinking process provided other important insights: 

1. To keep patients motivated, they need mental and emotional support.
2. There is a tension between the boredom caused by repetitive rehab exercises and the motivation gained from visible progress.
3. It is important to record individual progress and set realistic goals.
4. Instructions for rehab must be clear and easy to understand.
5. The sensor attachment devices planned so far have proven to be too challenging to use.

The project team then presented their interim results to Data4Life and asked for feedback. The company saw the greatest potential benefit in the instructions and handling of the sensors, which the students then focused on. 

A comprehensive solution was developed as a prototype: all the components needed for the “Sensor-S” study were combined in a box. These included the sensors themselves, the associated mounting options and simple instructions for use, positioning and establishing a Bluetooth connection with mobile devices. User experience and usability were at the forefront here – in line with the needs of patients and the expectations of our project partners.

The sensors for the left and right foot are in their own cases and are color-coded, formally identified, and labeled with the letters “L” and “R.” The buttons on the sensors are enlarged and also colored. The wide Velcro straps position the sensor cases on the midfoot with minimal slippage and jerking. Since they are elastic, they can be slipped over any shoe and any sock. The box includes compartments for technical set-up such as smartphones and/or smartwatches, which can be charged directly via integrated connectors. Likewise, clear instructions are placed wherever they are actually needed. This allows patients to use the box contents step by step and is also what gives the all-in-one box its name: “STEPbySTEP.”

The result and proposal of the HPI d-school project team is a compact sensor application that stands out from existing solutions due to its human-centered design.
 

The innovative all-in-one box from “STEPbySTEP” could help to implement sensor-based rehabilitation measures.

Many stroke patients find it difficult to consistently follow their prescribed recovery plan. “STEPbySTEP” supports them by offering an easy-to-use sensor service in a compact set. This consists of sensors with fastening straps, several charging options, and accessible instructions that use images and simple language. In particular, the elastic Velcro solutions, which allow the sensor cases to be intuitively attached to the feet, save the wearers a lot of frustration. 

Thanks to this optimization proposal from the Design Thinking process, they would face fewer difficulties, allowing the patients to focus entirely on their recovery. The more motivated they are, the more successful their rehabilitation will be – step by step.