Chinese Americans in the United States earn less than non-Hispanic Whites of the same educational level, despite having a higher educational level than the average population, a study has said.

The compilers of a 64-page report, A Portrait of Chinese Americans, analyzed data from the US Bureau of Census and the American Community Survey of 2006, science portal EurekAlert! Chinese reported last week.

The study, jointly carried out by the University of Maryland and the Organization of Chinese Americans (OCA), said there are twice as many college degree holders among Chinese Americans aged 25 and above than among the general population, but they earn less than non-Hispanic Whites of all levels of education.

"Chinese American men earn $5,000 to $15,000 less than non-Hispanic Whites with the same level of education," the report said.

The reasons behind the discrepancy include racial discrimination, perceptions of "a lack of leadership potential", and differences between Chinese Americans and the majority in "standing out" and "receiving recognition", Professor Larry Hajime Shinagawa of the University of Maryland, who led the study team, said.

Also, Chinese Americans do not earn increasing incomes with each successive generation, the study said.

Members of the "1.5 generation" - those who arrived in the US aged 15 or younger - receive the highest returns on their educational achievements, it said.

This is because these people have better language skills than their parents, the first generation, and are generally better educated, Michael Lin, executive director of the OCA and member of the research team, said.

The first generation has also not been totally Americanized, and still "maintains a drive" to pursue professional careers, he said.

While Shinagawa is optimistic about the future for Chinese Americans, he said the study implies a need for the development of "constituency groups" among Chinese and Asian Americans in the workplace that can lead to recognition, protection and advocacy.

Other ways to combat the lower income levels include sensitivity training for company managers, enforcement of civil rights laws, training programs for recognizing different kinds of leadership, and a redirection of management approaches, he said.