Despite known risks and available treatment, many adults diagnosed with hypertension (Htn) are undertreated and thus have uncontrolled blood pressure (BP). Typically, treatment decisions are made in response to a single BP measurement taken in a clinical setting that is often not reflective of a person’s ongoing BP. With home monitoring technology, patients can provide clinicians with ongoing measurements that are more reflective of their actual BP. However, the use of home monitoring results in numerous BP data points that are difficult to quickly evaluate. In addition, patient-generated home BP data are generally unavailable within the clinician’s electronic health record (EHR) workflow, often arriving as paper lists, which further increases the clinician’s cognitive load.

This research designed and tested a data visualization tool of both home- and clinic-derived BP data as a clinical decision support (CDS) tool that would help patients and clinicians use these data to better understand Htn control and inform shared treatment decisions.

The specific aims of the research were as follows:

• Determine patient and physician information needs about clinic and home BP data.
• Evaluate how characteristics of BP data interact with characteristics of the data display to influence patient and physician perceptions of BP control.
• Iteratively design a shared display of BP and medication data that will inform the work of patients and physicians making decisions together in the ambulatory setting.
• Examine patient-physician encounters to determine how effective shared display influences shared decision making and goal setting in ambulatory clinic visits for patients with Htn.

The data visualization tool integrates data from the EHR and patient-collected BP readings entered via a patient portal. Development used FHIR-based standards that allow the tool to be vendor agnostic and interoperable, and thus scalable. Their user-centered design process leveraged usability and design principles and included patient and physician information needs regarding the amount and type of data to display, informed by a series of focus groups. To determine how this decision support tool influenced patient and physician perceptions of control and risk, the research team conducted online experiments examining the effect of specific display elements and user health literacy, graph literacy, and numeracy. Finally, they recorded and analyzed videos from 89 patient visits for Htn to understand how EHR visualization decision support versus paper list presentation of BP readings influenced decision making.

The data visualization specifically addressed human factors to create improved meaning for patients and physicians, easing cognitive load and an improved shared decision-making process. Physicians and patients responded positively to the new designs, reporting enhanced and faster sense-making and patient engagement. The effect of implementing the CDS on Htn clinical outcomes and work to improve the patient-facing decision and self-management support are areas for future inquiry.