A relationship exists between the diversity of medical schools and the perceived preparation of white medical students to care for diverse groups of patients, according to a study being published today in the Journal of the American Medical Association.

The study found that white students who attend medical schools with greater racial and ethnic diversity in the student body are more likely to rate themselves as highly prepared to care for minority populations. Those white students within the highest quintile for student body diversity, measured by the proportion of underrepresented minority students, were 33 percent more likely to rate themselves as highly prepared to care for minority patients than were those in the lowest diversity quintile. The correlation between diversity and preparedness to care for minority patients was highest at medical schools where students perceived a high degree of interracial interaction.

The findings were based on a survey by the Association of American Medical Colleges to 20,112 graduating medical students (64 percent of graduating students in 2003 and 2004) from 118 medical schools in the United States. Historically black and Puerto Rican medical schools were excluded. For non-white students, the study did not find correlations between student body diversity and preparedness to serve diverse populations.

Generally, the study found that underrepresented minority students were much more likely than other students to plan to practice in areas not well served by medical services. Nearly half of underrepresented minority students plan to do so, while less than 20 percent of other medical students have such plans.

The findings about medical school -- and particularly about the impact of diversity on white students -- are being praised by supporters of affirmative action as strengthening a crucial legal argument in favor of allowing colleges and universities to consider race and ethnicity in admissions decisions. The Supreme Court's 2003 decision in Grutter v. Bollinger, upholding the right to consider race, specifically noted the argument that diversity has educational value and said that affirmative action is not intended simply to help individuals who gain admission under such policies. Similarly, the 1978 Supreme Court decision upholding affirmative action (while barring quotas) in admissions, Regents of the University of California v. Bakke, cited educational values -- and was decided with regard to medical school admissions, in that case at the University of California at Davis.

The new study's authors write that their work "lends empirical support for the Supreme Court's rationale" for upholding affirmative action in admissions. The study "indicates that a diverse student body is likely to be necessary but not sufficient.... Additionally, our analysis supports the concept of 'critical mass,' whereby a certain proportion of minority students is considered necessary to realize the benefits of diversity."

The authors are Somnath Saha of the Oregon Health and Science University, Gretchen Guiton of the University of Colorado at Denver, Paul F. Wimmers of the University of California at Los Angeles and LuAnn Wilkerson of UCLA.

Roger Clegg, president and general counsel of the Center for Equal Opportunity -- a group that opposes the consideration of race or ethnicity in admissions -- said in an e-mail that he found the new study "very unpersuasive." He said that the use of self-reporting was "dubious," but that -- even if accurate and linked to diversity -- he would reject this defense of affirmative action. "It does not follow that the only way to achieve these cross-cultural skills is through a diverse student body (versus, for instance, simply teaching the cross-cultural skills, which are not rocket science -- or brain surgery, if you like -- in class)." And even if the diversity does lead to better skill with treating a diverse group of patients, he said, that does not mean "that the improved cross-cultural skills are worth the price of discrimination."