Despite their status as the largest ethnic minority group in the United States, Latinos are often poorly represented in federally funded research and clinical trials.

For example, Latinos comprise 16 percent of the general population but represent only 7 percent of participants in research projects funded by the National Institutes of Health and just 2 percent of those in clinical trials overseen by the Food and Drug Administration.

Concepción Barrio, an associate professor with the USC School of Social Work, believes language and cultural issues may be partly to blame, particularly when researchers attempt to obtain consent from potential participants. She is partnering with colleagues at UC San Diego on a $1.4-million project to study the issue and develop an educational tool to improve overall research literacy among Latinos with schizophrenia.

“Underrepresentation of Latinos in research is both unethical and a major public health problem,” Barrio said. “In a general sense, Latinos don’t participate in research similar to other groups. Spanish-speaking Latinos are especially not well represented, particularly in drug trials.”

Led by Barrio and Barton Palmer, a professor of psychiatry with UC San Diego, the three-year project will involve exploring the degree to which language, acculturation, education and health literacy affect how well Latinos with schizophrenia or schizoaffective disorder understand and are satisfied with research procedures, particularly the informed consent process.

The study will include 60 Latinos who prefer speaking Spanish, 60 Latinos who prefer speaking English, and 60 non-Latino whites. Half of the participants will be randomly assigned to receive an educational presentation on key research-related topics, including a discussion of randomized trials and the difference between a medical doctor and a researcher.

“We will educate them on the research process so they are fully informed about what it entails,” Barrio said. “It really spells it out in an elegant and straightforward way.”

Latinos with schizophrenia often have cognitive limitations, she said, and issues such as translation of research instructions from English to Spanish can have unexpected consequences. For example, the Spanish word for research is investigación, which may trigger paranoia for some potential study participants.

In addition to measuring the effectiveness of the educational intervention—by testing variables such as comprehension of and satisfaction with the consent process and retention of information compared to a control group—Barrio said the project will also include interviews with 30 participants to gain insight about their perceptions of the research process and informed consent.

Examining the obstacles that impede the participation of Latinos in research is critical, particularly those with schizophrenia, a population Barrio has worked with throughout her career.

Latinos in general are more likely than other populations to experience weight gain and metabolic syndrome, an array of disorders that often leads to increased risk of diabetes and cardiovascular problems, she said. The use of some medications used to treat schizophrenia, often referred to as atypical or second-generation antipsychotics, has been known to induce metabolic syndrome.

Because so few Latinos participate in clinical trials, Barrio said it is difficult to develop guidelines for which medications to use when treating schizophrenia and other mental health disorders.

“Most major drug trials for schizophrenia include black and white populations,” she said. “The findings from those big studies are being generalized to all populations, but they cannot really be generalized to Latinos.”

Further complicating the matter is the fact that the Latino population is significantly heterogeneous in terms of culture, acculturation, level of education, and overall health literacy, Barrio noted. To address that issue, the study will delve into subgroup differences and explore the varying effects of language and other cultural factors on the informed consent process.

The project, which is funded by the National Institute of Mental Health, will run through April 2015. Participants are already being enrolled in the San Diego area.

Once the study is complete, Barrio and the research team plan to present their findings in professional publications and during meetings attended by psychiatric researchers and human subject protection officials.

The study team also plans to provide the Spanish and English versions of the educational intervention online, along with detailed instructions for their use, should other researchers find them useful for future studies.

Although the project will focus on people with schizophrenia, Barrio expects its findings to have implications for a broad range of clinical research topics.