Test–retest reliability of a mobile application of the patient reported outcomes burdens and experiences (PROBE) study

INTRODUCTION: The Patient Reported Outcomes, Burdens, and Experiences (PROBE) questionnaire is a patient-reported outcome tool that assesses quality of life and disease burden in people with haemophilia (PWH). AIM: To assesses the test-retest reliability of PROBE when completed using the mobile phone application. METHODS: We recruited PWH, including carriers, and individuals with no bleeding disorders who attended haemophilia-related workshops or via social media. Participants completed PROBE three times (twice on the app: T1 and T2, and once on the web, T3). Test-retest reliability was analysed for T1 versus T2 (app to app, time period one) and T2 versus T3 (app to web, time period two). RESULTS: We enrolled 48 participants (median age = 56 [range 27-78] years). Eighteen participants (37.5%) were PWH and seven (14.6%) were carriers. On general health domain questions, we found almost perfect agreement, except for a question on the frequency of use of pain medication in the last 12 months [Kappa coefficient (κ) .72 and .37 for time period one and two, respectively] and any use of pain medications (κ .75) for time period two. For haemophilia-related questions, we found substantial to perfect agreement, except for the questions on the number of joint bleeds in the previous 6 months for time period one (κ .49) and the number of bleeds in the previous two weeks for time period two (κ .34). CONCLUSIONS: The results demonstrate the reliability of the PROBE app. The app can be used interchangeably with the paper and web platforms for PROBE administration.