pubmed:affiliation |
Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill, NC 27599-7435, USA. djw@unc.edu
|
pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, Non-P.H.S.,
Research Support, Non-U.S. Gov't,
Research Support, N.I.H., Extramural
|