People who had access to translation services were also less likely to be readmitted for the same complaint within the next month, researchers found.

"Not only does providing professional interpretation make good medical sense, so patients understand their diagnosis and understand the care they are receiving better, but it also makes good economic sense for hospitals," said Dr. Mary Lindholm, the study's lead author from the University of Massachusetts Medical School in Worcester.

In 2009, the average inpatient visit in a U.S. hospital lasted 4.6 days and cost $9,200, or $2,000 a day, according to the federal Agency for Healthcare Research and Quality.

By cutting down length of stay and readmissions, the use of trained interpreters could reduce overall cost of care for hospitals, Lindholm told Reuters Health.

It can also mean smaller bills for patients.

"If we can provide adequate interpretation, it is much less expensive than having to readmit someone or having to keep somebody in a day and a half longer," Lindholm said.

The cost of an interpreter can run between $30 and $130 per hour, depending on whether a staff interpreter or someone hired from the outside is used, according to UMass officials.

Census statistics show an estimated nine percent of Americans struggle to communicate in English. Those people may be unable to explain their symptoms to a doctor who doesn't speak their native language, or to understand their doctor's instructions and treatment plan.

For the new study, Lindholm and her colleagues tracked treatment records for more than 3,000 patients with limited English skills admitted to a university hospital between 2004 and 2007.

Of these patients, 75 percent spoke either Spanish or Portuguese, 15 percent spoke Vietnamese, Albanian or Russian and the remaining 10 percent spoke one of 65 other languages.

All study participants used interpretation services at least once during their stay.

About 39 percent of them used professional interpreters on both the day they were admitted and the day they were discharged from the hospital. Fourteen percent had no interpreters on either day.

Overall, more than half of patients spent three or fewer days in the hospital, and three-quarters spent no more than five days, the researchers reported in the Journal of General Internal Medicine.

Lindholm's team found that patients with access to an interpreter at both admission and discharge stayed in the hospital for one and a half fewer days, on average, compared to those who didn't have language help at either time.

That was after taking into account patients' age, gender, language and severity of illness.

Length of stay was halfway in between for patients who had an interpreter at discharge, but not admission.

"We gather so much of the information about what is going on with the patient at admission. If you didn't take a good history because you didn't have a qualified interpreter, that might affect their length of stay," Lindholm explained.

More than 500 study participants were readmitted to the hospital within 30 days of their initial discharge. And patients who did not receive interpretation services at key points returned with the same complaint more frequently than those who did, the study found.

About 24 percent of those who did not have an interpreter at admission and discharge were readmitted within a month, compared with 15 percent among those with language assistance on both days.

Gerard Barsoum, director of interpreter services at Boston Medical Center, who wasn't involved in the new study, testified to the demand for professional interpretation in the community.

The study's findings are in line with "mounting evidence that shows professional medical interpreters help improve the quality of care as well as reduce costs, length of stay and readmission for patients who have limited English proficiency," he told Reuters Health in an email.

SOURCE: bit.ly/LMtNb4 Journal of General Internal Medicine, online April 18, 2012.

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