Most California adults don’t get a flu shot every year, but members of certain racial or ethnic groups are less likely to be immunized, according to a new study.

In California, black adults were 33 percent less likely than white adults to have received a flu shot in the past year, researchers found. Meanwhile, Korean and Vietnamese adults were more likely than white adults to have been vaccinated in the past year.

Only 35.8 percent of California adults had received a flu shot in the past year, the study found.

Adults who had a chronic condition, graduate degree, insurance, usual source of care or had seen a physician in the last year were more likely to have been vaccinated.

Researchers from Cedars-Sinai Medical Center and UCLA used data from the 2011-2012 California Health Interview Survey, analyzing responses from 27.8 million adults.

Rates of flu vaccinations for other racial and ethnic groups, including Latino, Japanese, Chinese, Filipino, South Asian and Asian, were comparable to rates for whites after adjusting for demographic, socioeconomic and access-to-care factors. When researchers didn’t adjust for those factors, Latinos had among the lowest vaccination rates.

The researchers said that public health agencies should use culturally sensitive education materials when trying to increase vaccination rates, particularly in black communities.

The study shows that there is “evidence of racial and ethnic disparities in flu vaccination update,” researchers wrote.

“As the ACIP (Advisory Committee on Immunization Practices) calls for near-universal flu vaccination, accelerated efforts to create interventions to increase vaccination update among these groups are needed.”