The future role of health centers in improving national health.

International health rankings for the US are heavily influenced by striking racial and socioeconomic health status disparities. Current discussions of health determinants frequently relegate or entirely dismiss health care contributions despite increasing evidence of the importance of access to primary care. Health centers deliver community-based primary care to a considerable and growing proportion of the nation's most vulnerable and have produced significant health improvements, especially for women and children. Policies that disproportionately benefit those in greatest need are likely to produce the largest gains in national health. Continued expansion of the health center network to ensure primary care for those who remain underserved is both an effective and politically acceptable strategy to improve national health.