A smartphone application for remote adjustment of warfarin dose: Development and usability study

The aim of this article is (a) to design and develop a smartphone app called Alfalfa that can provide remote dose adjustment (b) to evaluate its usability.Patients taking warfarin need to spend substantial time, money, and energy frequently visiting the hospital in order to adjust its dose. Internet technology may be able to provide convenient dose adjustment services for these patients.We thought and discussed repeatedly about how to ensure the safety and effectiveness of remote administration of warfarin, and finally designed and developed the Alfalfa app. In addition, patients and medical practitioners were invited to participate in a system usability scale (SUS) to assess the usability of Alfalfa.As of July 5, 2021, the number of Alfalfa accounts was 1736, including 1624 patients and 112 medical staff, and it provided a total of 12,968 remote dose adjustments. A total of 26 people participated in the questionnaire, including 15 patients and 11 medical staff. The results of SUS show that the usability score of patient terminal and medical terminal is 61.8 and 82.7, respectively. And age does not affect the usability of patient terminal. The usability of the Alfalfa app was rated similarly by younger and older adults (63.5 vs. 58.5, P = .535).This study proves that the Alfalfa app can be used for remote management of warfarin. The usability of medical terminal is acceptable to medical practitioners, while the usability of patient terminal needs further improvement.ChiCTR1900021920.