Delivering Patient-Facing Evidence-Based Guidelines through mHealth to Adults with Sickle Cell Disease (PF-Guide) - PROJECT SUMMARY We propose a multi-center hybrid type I effectiveness-implementation trial to assess patient-facing evidence- based guidelines through a mHealth application plus (+) booklets in adults with sickle cell disease (SCD). Clinicians’ care of SCD is informed by evidence-based guidelines, which target the prevention of morbidity and mortality. The National Heart, Lung, and Blood Institute (NHLBI) and the American Society of Hematology (ASH) published guidelines for evidence-based management of SCD for healthcare providers. However, patient, provider, or system barriers prohibit adequate reach within and across all three domains, leading to poor guideline adherence. Our prior work demonstrates 1) the patient’s lack of knowledge of evidence-based guidelines, 2) the desire for guidelines to be patient-centered, accessible, and actionable in booklets and a mHealth app, 3) the development of patient-facing booklets with the guidelines, and 4) the successful pilot of an engaging mHealth app with the guidelines that adults with SCD will use. Promising preliminary data from our multi-center feasibility randomized controlled trial support using a mHealth app + booklets with patient-facing guidelines for reducing acute healthcare utilization in adults with SCD. In this feasibility trial, 91% (67 of 74) of screened participants were recruited and randomized into one of the two arms: (1) mHealth + booklet arm or (2) booklets alone arm. A total of 75% (50 of 67) of the participants agreed to be followed up for six months to assess healthcare utilization and answer surveys of knowledge and patient- reported outcomes. The mHealth + booklet arm had a 44% reduction in relative risk in acute healthcare utilization (a decrease of 1.5 emergency room visits or hospital admissions per year) compared to the booklet alone arm. Based on the preliminary results, we propose a three-center randomized controlled trial in adults with SCD (n=272) to test the following hypothesis: There will be a 44% relative risk reduction of acute healthcare utilization in adults with SCD, randomly allocated to mHealth app + booklets vs. standard care, defined as general guidance without patient-facing educational materials, for 12 months. The aims of this proposed study are Aim 1: evaluate the effectiveness of the patient-facing guidelines mHealth app + booklet intervention to decrease acute healthcare utilization (hospitalizations, emergency room visits, and day hospital visits) in adults with SCD over the standard care in a randomized controlled trial. Aim 2: evaluate the implementation outcomes of the mHealth app + booklet using the capability, opportunity, and motivation- behavior (COM-B) and reach, effectiveness, adoption, implementation, and maintenance (RE-AIM) frameworks and Aim 3: evaluate the cost-effectiveness of patient-facing mHealth app + booklets vs. standard care in adults with SCD. This hybrid effectiveness-implementation trial design, according to the COM-B and RE-AIM frameworks with a mixed-methods approach, will give valuable insights into the effects, facilitators, and barriers to the implementation that will influence the effects of the patient-facing guidelines intervention.