Effect of Expansion of Abbreviations and Acronyms on Patient Comprehension of Their Health Records: A Randomized Clinical Trial

In 2020, an estimated 100 million US residents accessed their health records online.¹ That number likely increased beginning April 2021, when US federal rules implemented the 21st Century Cures Act requiring electronic health information to be made freely accessible.² Unfortunately, medical abbreviations and acronyms often limit patient understanding of health records. Automated expansion is one potential solution; however, it is unclear whether the magnitude of its effect is sufficiently large to justify costly implementation at scale. In this prospective, 2-arm, parallel, individually randomized clinical trial at 3 US hospitals in metropolitan areas, we estimated how much expansion increases patient comprehension of 10 common abbreviations in their health records.

This trial used a purposive sample representative on age, gender, and race that was enrolled between February 2020 and August 2021 (ClinicalTrials.gov NCT05297942) (trial protocol and statistical analysis plan in Supplement 1). To isolate the main effect, we included only English-speaking adult patients with diagnosed heart failure. The Weill Cornell Medicine institutional review board approved the study and all participants provided written informed consent. This trial followed the Consolidated Standards of Reporting Trials Extension (CONSORT Extension) reporting guideline (eFigure in Supplement 2).

Participants were individually randomized to read clinical text with abbreviations (control group, 30 participants) or with expansions (intervention group, 30 participants). The abbreviations and expansions included were hrs (hours), MD (medical doctor), BP (blood pressure), ED (emergency department), yo (year old), pt (patient), HF (heart failure), hx (history), HTN (hypertension), and MI (myocardial infarction). We included abbreviations and expansions of varied difficulty as rated by clinicians (data available upon request).

The primary outcome was overall comprehension, assessed using the International Organization for Standardization Method for Testing Comprehension (ISO 9186),^3,4 and defined as the summary (ie, count) score of the total number of abbreviated or expanded terms comprehended. Baseline demographics, socioeconomic characteristics, and health literacy scores⁵ were collected. Race and ethnicity was self-reported and collected for purposive sampling. For the primary outcome, P < .05 in 2-sided tests was considered significant.

Sixty randomized patients (mean [SD] age, 66 [16] years; 18 [30%] women) completed the trial and were included in the analysis (Table 1). Overall comprehension scores were significantly greater among patients in the intervention group who received expansions than among patients in the control group who received abbreviations (95% vs 62%, respectively; comprehension score, 9.5/10 [95% CI, 9.3 to 9.7] vs 6.2/10 [95% CI, 5.3 to 7.0]; P < .001).

Significant differences in comprehension were observed only for moderately difficult terms such as HTN (hypertension) (Table 2). In a subgroup analysis of control participants, only inadequate health literacy was significantly associated with comprehension of fewer abbreviations (adjusted risk ratio, 0.69; 95% CI, 0.49 to 0.98; P = .04).

Expansion of 10 common medical abbreviations compared with no expansion significantly increased overall comprehension of the abbreviations from 62% to 95%. These findings suggest that post hoc or automated expansion of medical abbreviations and acronyms can improve patient understanding of their health information, and may benefit ongoing national efforts to provide patients with electronic access to their own documentation.

Even in this population with substantial prior exposure to the health care system, comprehension of common abbreviations such as MI or HTN remained below 40%, much lower than clinicians initially estimated. Clinicians should be mindful that patient comprehension of abbreviations may be much lower than expected.⁶ Additionally, our data suggest that expansion is an efficacious standalone solution only for certain abbreviations and acronyms. Abbreviations with well-understood meanings while abbreviated (eg, hrs, MD) and poorly understood meanings while expanded (eg, myocardial infarction) did not benefit significantly from the intervention.

This study had several limitations. Ethnicity was imbalanced between study groups by chance; however, sensitivity analyses using multivariable models that controlled for study group and ethnicity demonstrated the imbalance did not affect our conclusions. We restricted our sample to 1 disease condition, which was necessary to isolate the main effect. Results may not generalize to other populations.

Accepted for Publication: March 29, 2022.

Published: May 13, 2022. doi:10.1001/jamanetworkopen.2022.12320

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2022 Grossman Liu L et al. JAMA Network Open.

Corresponding Author: Lisa Grossman Liu, PhD, Department of Biomedical Informatics, Columbia University, 622 W 168th St, PH-20, New York, NY 10032 (lvg2104@cumc.columbia.edu).

Author Contributions: Dr Grossman Liu had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Grossman Liu, Vawdrey, Masterson Creber.

Acquisition, analysis, or interpretation of data: Grossman Liu, Russell, Reading Turchioe, Myers, Masterson Creber.

Drafting of the manuscript: Grossman Liu.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Grossman Liu, Russell.

Obtained funding: Grossman Liu, Masterson Creber.

Administrative, technical, or material support: Grossman Liu, Reading Turchioe, Myers, Masterson Creber.

Supervision: Grossman Liu, Vawdrey, Masterson Creber.

Conflict of Interest Disclosures: Dr Reading Turchioe reported receiving nonfinancial support from Iris OB Health LLC, grant funding from National Institutes of Health, and consulting fees from Boston Scientific outside the submitted work. No other disclosures were reported.

Funding/Support: This work was supported by the National Institute of Nursing Research (No. R00NR016275; principal investigator, Masterson Creber) and the National Library of Medicine (No. F31LM054013; principal investigator, Dr Grossman Liu).

Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Data Sharing Statement: See Supplement 3.

Additional Contributions: We gratefully acknowledge the support and contributions of the patients and health care providers who participated in the study. Thank you to George Hripcsak, MD, MS, Suzanne Bakken, PhD, RN, Jessica Ancker, PhD, MPH, and Wanda Pratt, PhD, for your support regarding the design, analysis, and manuscript. These contributors received no additional compensation.