Effectiveness of the SelfBack-App in Preventing and Treating Low Back Pain Versus no Intervention: a Non-randomized Clinical Trial

Low back pain (LBP) is a frequent condition that can affect daily functioning, physical activity, and work participation. Healthcare professionals, including nurses, assistant nurses, and logistical staff, are considered a population at increased risk because their professional activities often involve physical demands such as patient handling, repetitive movements, prolonged standing, and manual tasks.

The present study evaluates the effectiveness of the SelfBack application, a digital decision-support system designed to support the prevention and self-management of non-specific low back pain. The SelfBack system provides participants with individually adapted weekly recommendations through a smartphone application. These recommendations consist of exercise suggestions, activity goals, and educational information aimed at supporting participants in managing their symptoms and maintaining physical activity.

The study was initially designed as a single-centre clinical trial. Following an amendment dated 17/07/2026, the study was expanded into a multicentre trial to include an additional recruitment site. In addition to Universitair Ziekenhuis Brussel (UZ Brussel), Ziekenhuis Valida will participate in the recruitment of participants. This modification was introduced because recruitment was progressing more slowly than initially expected. Expanding recruitment to a second centre allows a larger number of eligible healthcare workers to be approached and improves the feasibility of completing participant inclusion within the planned timeframe.

The study compares two approaches: usual care combined with access to the SelfBack application and usual care without additional digital intervention. The aim is to determine whether the addition of a digital self-management support system can improve outcomes related to low back pain compared with usual care alone.

The SelfBack application is a digital decision-support system that provides participants with a personalized weekly self-management plan. The recommendations are generated based on information collected from the participant and are adapted according to changes in symptoms and activity levels throughout the intervention period.

Participant information is obtained through an initial questionnaire, repeated self-reports within the application, and activity information collected through a step-counting device. These data are used by the SelfBack system to provide recommendations that correspond with the participant's individual situation.

Exercise adherence is monitored through the application, where participants indicate whether suggested activities have been performed.

The SelfBack application is used only for delivering the intervention content, including educational information, activity recommendations, and exercise guidance. Study questionnaires and Patient-Reported Outcome Measures (PROMs) are collected separately through REDCap.

This study is designed as a multicentre randomized controlled clinical trial with two parallel groups. Participants are recruited among healthcare workers employed in selected departments of UZ Brussel and Ziekenhuis Valida.

Allocation to the intervention or control condition is determined according to the department in which participants work. This approach allows implementation within the clinical environment while avoiding practical difficulties associated with individual randomization among colleagues working in the same unit.

Participants allocated to the intervention group receive access to the SelfBack application in addition to usual care. Participants allocated to the control group continue with usual care without access to the digital intervention during the study period.

The study follows a pragmatic design, meaning that participants continue to receive the usual healthcare support available in their normal setting. Additional treatments, such as consultations with healthcare professionals, physiotherapy, or medication use, are not restricted and may continue according to standard practice.

The total duration of participation is twelve months. Follow-up assessments are performed after three, six, and twelve months to evaluate changes over time.

Before any study-related procedure takes place, participants receive information about the study and are given sufficient opportunity to consider participation. Written informed consent is obtained before enrolment.

The informed consent procedure has been adapted to allow electronic signing of the informed consent form. Participants can complete the electronic informed consent process when they are logged into a hospital computer using their personal identification through the badge reader system. This modification was introduced to simplify the consent procedure while maintaining secure identification of participants.

Data collection within this study is performed digitally. All study-related questionnaires and Patient-Reported Outcome Measures (PROMs) are collected through REDCap (Vanderbilt University, Nashville, USA), which is used as the Electronic Data Capture (EDC) system for the registration and management of study data.

The SelfBack application remains the digital tool used for delivering the intervention, including educational information, exercise recommendations, and personalized activity plans. REDCap is used specifically for collecting and storing study questionnaires and clinical research data.

Access rights are assigned according to the responsibilities of each study team member and are controlled throughout the study period. Study data are entered within a reasonable timeframe following completion of study assessments. Any modifications made to entered data are automatically documented through an audit trail, including information regarding the date, time, and person responsible for the modification.

All collected information is handled according to applicable data protection requirements.

After enrolment and completion of the informed consent procedure, participants start the study according to their assigned study group.

Participants allocated to the control group continue receiving usual care and complete the scheduled questionnaires through REDCap. Participants allocated to the SelfBack intervention group receive access to the SelfBack application in addition to usual care. They use the application to receive personalized exercise recommendations, educational content, and activity goals.

The follow-up period lasts twelve months. Participants complete digital questionnaires at three predefined assessment moments: three months after study enrolment; six months after study enrolment; twelve months after study enrolment.

The primary evaluation moment occurs after three months, corresponding with the main intervention period. Additional follow-up assessments at six and twelve months are performed to evaluate whether observed changes are maintained over time.

No physical study visits are required during the follow-up period. Communication and data collection occur digitally. If participants experience worsening symptoms or severe complaints during the study, they are advised to contact their usual healthcare provider according to standard care procedures.

The study evaluates the impact of the intervention through several questionnaires assessing physical functioning, symptoms, psychological factors, work-related outcomes, and quality of life.

All Patient-Reported Outcome Measures are completed digitally through REDCap at baseline and during follow-up assessments at three, six, and twelve months.

The primary outcome measure is the Roland Morris Disability Questionnaire (RMDQ). This questionnaire evaluates limitations in daily activities related to low back pain. Participants indicate whether specific functional difficulties are present, with higher scores representing greater functional impairment.

Additional questionnaires are used to evaluate different aspects related to low back pain and its impact on daily life.

Functional disability is additionally assessed using the Oswestry Disability Index (ODI), which measures disability associated with spinal disorders.

General health status and well-being are evaluated using the PROMIS-29 questionnaire. This questionnaire assesses several domains, including physical functioning, pain interference, fatigue, sleep problems, anxiety, depression, and social participation.

Work-related functioning is evaluated using the Work Ability Index (WAI) and work status questionnaires. These assessments examine the participant's ability to perform work activities and monitor changes in employment situation or work adaptations.

Health-related quality of life is assessed using the EQ-5D-5L questionnaire, which evaluates mobility, self-care, daily activities, pain or discomfort, and anxiety or depression.

Pain intensity is measured using a numerical pain rating scale ranging from 0 to 10, where 0 represents no pain and 10 represents the worst imaginable pain.

Psychological factors related to low back pain are assessed using questionnaires measuring kinesiophobia, fear-avoidance beliefs, and pain self-efficacy. These include the Tampa Scale of Kinesiophobia (TSK), the Fear Avoidance Belief Questionnaire (FABQ), and the Pain Self-Efficacy Questionnaire (PSEQ).

Physical activity is assessed through step-count data, recommended activity goals, and reported exercise volume. Participants in the intervention group provide information regarding completion of recommended exercises through the SelfBack application.

The Saltin-Grimby Physical Activity Level Scale is used to classify participants according to their general level of physical activity.

Healthcare-related resource use is documented through participant-reported information regarding medication use, physiotherapy sessions, and healthcare consultations related to low back pain.

Participants using the SelfBack application are also asked to provide user ratings regarding their experience with the application. These ratings assess overall satisfaction, ease of use, and willingness to recommend the application to others using a five-point scoring system.

The SelfBack application records information regarding participant interaction with the intervention. Participants are asked within the application whether recommended exercises have been completed and can indicate their performed activities.

However, the study does not include direct verification of exercise performance. Reported adherence therefore reflects participant-reported completion of activities.

The tailoring variables used by the SelfBack system are monitored during the intervention period. These variables include information related to pain intensity, function, fear-avoidance, work ability, sleep, pain self-efficacy, stress, depressive symptoms, and barriers to self-management.

The collected information allows the application to adapt recommendations according to the participant's reported status and progression.

The SelfBack application is considered a CE-marked Class I medical device. Based on the nature of the intervention, no serious adverse events are expected during this study.

A possible adverse event related to participation could be temporary worsening of low back pain due to muscular overload associated with performing exercises. This could occur following repetitive movements or increased physical strain.

If participants report worsening symptoms, they will be advised to seek medical advice from their usual healthcare provider according to standard clinical practice.

Serious adverse events are defined according to applicable medical device study regulations. No serious adverse events or suspected unexpected serious adverse reactions are anticipated for this clinical trial.

Inclusion criteria

• Currently working as a nurse, assistant nurse - logistical assistance in one of the selected units of the Universitair Ziekenhuis (UZ) Brussel, Valida or Inkendaal
• Presence or not of LBP of any duration
• Age: ≥18 years
• Own and regularly use a smartphone (with at least Android 7.0 or iOS11.0) with internet access (Wi-Fi and/or mobile data)
• Have a working email address and have access to a computer with internet access to complete questionnaires in a web browser.

Exclusion criteria

• Unable to speak, read or understand the national languages (Dutch/French/German) nor English
• Presence of red flags as described in the KCE LBP guidelines
• Work leave for medical reasons of more than 3 consecutive days during the last 6 months
• Cognitive impairments or learning disabilities limiting participation
• Mental or physical illness or condition limiting participation
• Inability to take part in exercise or physical activity
• Pregnancy
• Previous back surgery
• Ongoing participation in other research trials for LBP management