Development and effectiveness of a user-centered mobile application for informal caregivers of people living with dementia: randomized controlled trial

Abstract Background Dementia places substantial physical, psychological, and social demands on informal caregivers, and caregiving needs may change across the dementia trajectory as cognitive, behavioral, and functional changes alter day-to-day care demands. Digital interventions may not fully address caregivers’ evolving and heterogeneous needs and preferences. This study aimed to develop a user-centered mobile application informed by caregiver-identified needs and preferences across the dementia trajectory and to evaluate its effectiveness. Methods A randomized controlled trial was conducted following a qualitative intervention-development phase. The intervention was developed in accordance with the Medical Research Council framework for complex interventions and informed by principles of person-centered dementia care and qualitative interviews with informal caregivers. The application provided dementia education; communication and daily-care guidance organized to reflect changing caregiving needs; guidance for behavioral and psychological symptoms; caregiver self-care and stress-management resources; information on formal and informal support services; and customizable reminders. Caregivers were randomized to receive usual care with access to the mobile application for 8 weeks or usual care alone. Outcomes included caregiver burden (Zarit Burden Interview), quality of life (WHOQOL-BREF), neuropsychiatric symptoms (Neuropsychiatric Inventory), and caregiver distress related to these symptoms. System usability was assessed post-intervention in the intervention group. Outcomes were assessed at baseline and week 8 using repeated-measures analysis of variance. Results A total of 86 caregivers were randomized, of whom 75 were included in the analysis (intervention, n = 37; control, n = 38). Significant group-by-time interactions were observed for overall quality of life ( p < 0.001) and the psychological domain ( p < 0.001), with greater improvements in the intervention group than in the control group. No significant group-by-time interactions were observed for caregiver burden, neuropsychiatric symptom severity, or caregiver distress. The application demonstrated good usability at week 8. Conclusions The user-centered mobile application was associated with improvements in overall and psychological quality of life among participants included in the 8-week analysis, while no significant intervention effects were observed for caregiver burden, neuropsychiatric symptoms, or caregiver distress. Larger studies with longer follow-up and more detailed assessment of application engagement are needed to evaluate the durability and broader effects of the intervention. Trial registration This trial was registered at ClinicalTrials.gov (Registration number: NCT06179667 , Date of registration: 27 November 2023).