JMIR Publications

ABSTRACT

Background:

The global burden of obesity continues to rise, highlighting the need for patient-centered approaches to weight management. Shared decision making is particularly important in the selection of antiobesity medications (AOMs), as treatment options differ in mechanism, effectiveness, side effects, administration routes, and cost. Despite this preference-sensitive context, few patient decision aids (PDAs) have been culturally and clinically adapted for use in Asian populations.

Objective:

This study aimed to design, develop, and evaluate a digital PDA, OptiWeight, to support shared decision-making for AOM selection, incorporating perspectives from healthcare professionals and patients.

Methods:

This mix-methods, multi-center study, conducted between August 2022 to November 2025, employed a four-stage human-centered design process. An evidence-informed prototype was developed based on clinical guidelines, followed by two rounds of usability testing using think-aloud protocols to access navigation structures, perceived usability (System Usability Scale, SUS), and cognitive workload (NASA Task Load Index, NASA-TLX). Semi-structured interviews with weight-management healthcare professionals, guided by the Consolidated Framework for Implementation Research, informed clinical implementation and workflow integration. Finally, patients with overweight or obesity evaluated usability, cognitive workload, and overall user experience in outpatient settings. Qualitative data were analyzed using content analysis, and one-way ANOVA examined changes in usability and workload across stages.

Results:

A total of 174 individuals were included across all study stages (usability testing among adults: n=78; healthcare professional interviews: n=18; clinical evaluation among patients: n=78). Iterative usability testing comparing linear and non-linear navigation structures revealed complementary strengths and limitations, leading to the adoption of a hybrid navigation structure supporting both sequential guidance and flexible comparison. Additional design requirements included the use of icon arrays to enhance risk comprehension and localization features such as treatment cost displays and clarification of socially impactful side effects. Perceived usability improved significantly from initial testing to the clinical evaluation (SUS: 60.53 to 73.65, p <0.001), meeting good usability thresholds, while cognitive workload decreased substantially (NASA-TLX: 40.35 to 16.69, p <0.001).

Conclusions:

Through a systematic human-centered design process integrating healthcare professional and patient perspectives, OptiWeight addresses the lack of culturally adapted PDAs for AOM decision-making in Mandarin-speaking populations while captures user needs—particularly regarding navigation flexibility and risk visualization. The final tool demonstrated strong usability and clinical feasibility, supporting its potential integration into routine weight-management care. Clinical Trial: 1. Research Ethics Committee, National Taiwan University, 202206ES059, https://ord.ntu.edu.tw/w/ordntuEN/REC 2. Institutional Review Board, Taipei Veterans General Hospital, 2024-01-013AC, https://wd.vghtpe.gov.tw/irb/Fpage.action?muid=7091&fid=7427 3. Taipei Medical University – Joint Institutional Review Board, N202403021, https://ohr.tmu.edu.tw/zh-Hant/jirb/38