Background: Health literacy (HL) is a cornerstone for favorable and equitable health outcomes, yet nearly 9 in 10 U.S. adults struggle with limited HL associated with higher rates of hospital readmissions, medication nonadherence, and all-cause mortality. This disproportionately affects marginalized populations, especially those from racial and ethnic minorities. While the 21st Century Cures Act aims to mitigate differential access to health information by providing patients with access to their clinical notes in electronic health records (EHRs), most are unable to utilize them for health-based decisions and adequate management of care. As health systems shift towards a culture of shared decision-making, limited readability of EHRs remains a key barrier in our goal of empowering patients as agents of their own care. Thus, there is a critical need to improve comprehensibility of clinical notes and facilitate equitable outcomes at a systems level. Here, we evaluate the utility of GPT4-based plain language translation of discharge summary notes (DSNs) on subjective and objective comprehension, confidence, and time spent reading as well as its differential effect on various patient demographics.

Methods: 553 patients were enrolled from December 2023 to February 2024 and read four DSNs (two untranslated, two GPT4-translated) on common admission diagnoses on an inpatient general medicine service: congestive heart failure (CHF), community acquired pneumonia (CAP), diabetic ketoacidosis (DKA), acute ischemic stroke (AIS). After reading each DSN, patients answered questionnaire items assessing subjective perceptions and objective accuracy of comprehension. Linear mixed models were used to analyze effects of translation on comprehension outcomes.

Results: Across all four DSNs, GPT4-based translation improved objective comprehension by 61% (β=1.18, p<0.001), reduced time spent reading by 51% (β=-0.57, p<0.001), improved self-reported confidence by 45% (β=1.94, p<0.001), and improved subjective comprehension by 18% (β=2.32, p<0.001). It also strengthened the association between patient confidence and objective comprehension by 67% (p<0.01). Improvements were greater in Black and Hispanic patients, older patients, male patients, and those who reported limited health knowledge (p<0.01). In particular, objective comprehension improved an additional 22% and 39% among Black and Hispanic patients respectively (p<0.01).

Conclusion: GPT4-based translation of DSNs substantially improved patient comprehension of disease course and management while optimizing time spent reading them, and to a greater degree in marginalized populations with historically low rates of HL. Implementation of GPT4-translation in EHR interfaces for a patient-friendly supplement to provider notes offers great promise in closing the health literacy gap across a spectrum of patient demographics in medicine.