Asian Americans have historically been perceived as a "model minority," experiencing few health problems relative to other minority groups. Research within the past 20 years, however, has shown that Asian Americans are at high risk for hepatitis B, liver cancer, tuberculosis, and lung cancer, among other conditions. Asian American health disparities have only gained focus in the past 10 years, with policy initiatives geared towards promoting healthcare access to Asian Americans rising to prominence even later. Asian Americans are defined as Americans of Asian ancestry and constitute nearly 5% of American's population as of 2003, according to the U.S. Census Bureau. Yet, the Asian American population can hardly be described as homogenous. The term applies to members of over 25 groups that have been classified as a single group because of similar appearances, cultural values, and common ethnic backgrounds. The Asian Americans commonly studied have been limited primarily to individuals of Cambodian, Chinese, Filipino, Hmong, Japanese, Korean, Lao, Mien, or Vietnamese descent. Health disparities Asian Americans are a heterogeneous group. The racial class is composed of many different ethnicities and cultures. In addition to country of origin, individuals can differ in socioeconomic status, education level, immigration status, level of acculturation, and English proficiency. In general, ethnic groups have their own health disparities. Vietnamese and Filipino Americans tend to have poorer health outcomes compared with Chinese, Japanese, and Korean Americans. Self-rated health was lowest in Vietnamese Americans, while Filipino Americans have the highest rates of chronic diseases, including asthma, high blood pressure, and heart disease. Filipinos are also an ethnic group that is a risk factor for premature births and amyotrophic lateral sclerosis (ALS or "Lou Gehrig's disease"). Koreans exhibit the highest psychological stress out of all ethnic groups. Thus, to classify and generalize health disparities to such a heterogeneous group may not be beneficial; however, a few health statistics can still be gleaned from general trends. Genetic inherited disorders and diseases (e.g. colorblindness, hemophilia) were reported to be uncommon in all Asian ethnic groups. Cardiovascular disease Cardiovascular disease is one of the leading killers in all ethnic groups and a major contributor to disability among older adults. The incidence of heart disease is known to increase with age and the majority of deaths from Coronary Artery Disease occur in people ages 65 years and older. While the rates of death from cardiovascular disease are lower for Asian Americans relative to