Language Proficiency and Adverse Events in U.S. Hospitals: A Pilot Study

In the Literature

When patients have trouble communicating with their doctors, the consequences can be grave: mistrust, dissatisfaction with care, even medical errors. When patients have limited English proficiency (LEP), communication problems can be even more serious. Despite the rising number of LEP individuals in the United States—from 6 percent of the population in 1990 to 8 percent in 2000—little is known about the impact of language barriers on patient safety.

In "Language Proficiency and Adverse Events in U.S. Hospitals: A Pilot Study" (International Journal for Quality in Health Care, April 2007), Commonwealth Fund–supported researchers from the Joint Commission report on the type and frequency of adverse events experienced by LEP and English-speaking patients in six U.S. hospitals. Their findings are startling: LEP hospital patients are more likely than their English-speaking counterparts to experience adverse events that result in harm, and the severity of that harm is often greater.

Understanding the Causes of Adverse Events
The researchers reviewed 1,083 adverse event reports, involving both English-speaking and LEP patients, at six hospitals between February and August 2005. To categorize the reported incidents, the researchers used the Joint Commission's "Patient Safety Event Taxonomy," a system designed to allow standardization and comparisons of adverse event reports. The hospitals reported medication mistakes, patient falls, injuries during treatment, skin breakdowns, and equipment problems, among other events.

Patients with Limited English Experience More Serious Errors
The researchers found that LEP patients were more likely than English-speaking patients to experience an adverse event that caused some physical harm (49% vs. 30%). What's more, a greater proportion of adverse events among LEP patients resulted in moderate or severe—albeit temporary—harm.

The researchers considered the processes related to adverse errors, including those involving communication (e.g., advice, information, disclosure, or consent), management (e.g., tracking or follow-up of patients), and clinical performance (e.g., diagnoses or interventions). Not surprisingly, LEP patients experienced a significantly greater proportion of adverse events attributable to communication than did English-speaking patients (52% vs. 36%).

Looking more closely at the communication processes, the researchers found that, compared with English-speaking patients, LEP patients experienced a greater proportion of events that could be attributable to questionable advice or interpretation (11% vs. 4%). The same trend was found for adverse events attributable to the questionable assessment of patient needs (15% among LEP patients, compared with 6% among English-speaking patients).

The researchers also considered the cause of adverse events—specifically, the system or human errors that can bring about an error or failure. Overall, they found that organizational factors—like knowledge transfer or protocols and processes—played a greater role in relation to adverse events among LEP patients than they did for English-speaking patients (66% vs. 54%).

Language Services, Data Collection Are Needed
It is notable, the researchers say, that LEP patients experienced more events attributable to questionable advice or interpretation, as well as problems related to disclosure of their conditions or needs. This finding suggests that some providers may not be sharing pertinent information or adequately discussing the implications and outcomes of care with LEP patients.

The study points to the need for strategies to ameliorate language barriers and thus improve the safety and quality of care. The authors recommend that hospitals provide language services, relying on trained medical interpreters. Hospitals should also indicate patients' native language and communication needs in their records and document the language services provided during medical encounters—as required by a Joint Commission accreditation standard implemented in January 2006. Such information will help hospitals characterize adverse events and understand how language plays a role in patient safety.

"Having uniform access to these types of data allow hospitals to examine their processes, identify areas for improvement and initiate efforts to address any disparities in outcomes for LEP patients," the authors conclude.

Facts and Figures

• Among 251 adverse events involving patients with limited English proficiency (LEP) at six hospitals over a seven-month period, 130 (52%) were related to communication problems.
• Among 832 adverse events reported for English-speaking patients over the same period, 299 (36%) were related to communication problems.
• Nearly one of five (19%) reported adverse events among LEP patients resulted in moderate temporary harm. A small number (4%) resulted in severe temporary harm or death—more than twice the rate that occurred among English-speaking patients.