Medical errors are common for patients with limited English proficiency. Errors are especially common when the interpreter is a family member or other untrained person.
The study was reported in the October issue of Medical Care.
In contrast, the error rate is cut in half when trained medical interpreters are used, whether in person or by video conference.
Researchers found full deployment of professional interpretation capacity for limited English proficiency patients is a quality of care issue whose time has come.
The study analyzed the accuracy of medical interpretation during 32 primary care visits with Spanish-speaking patients at a public hospital clinic. The visits were audiotaped and transcribed. The tapes and transcripts were assessed to determine the rate of errors in medical interpretation, including errors likely to have a clinically significant impact on patient care.
The overall error rate was found to be about 30% based on the number of “text units” analyzed.
Errors of omission and answering for the patient or health care professional were the most common types of interpreter errors.
Errors were about twice as common in visits with ad hoc interpreter: 54% compared to 25% with trained interpreters.
The differences remained significant after there was adjustment for other patient and visit related factors.
The odds of a clinically significant error were about 75% lower in visits with trained in-person interpreters compared to ad hoc interpreters.
Clinics and hospitals that receive federal funds are required to provide interpretation services for patients with limited English proficiency.
The results of this study add to previous evidence that shows that medical interpretation errors are common in visits with limited English proficiency patients.