[1] Univ Pittsburgh, Inst Diabet, Pittsburgh, PA 15213 USA
[2] Univ Michigan, MI Diabet Res Training Ctr, Ann Arbor, MI 48109 USA
[3] Loyola Coll, Dept Sociol, Baltimore, MD 21210 USA
[4] Johns Hopkins Univ, Dept Med, Baltimore, MD USA
[5] Johns Hopkins Univ, Dept Pediat, Baltimore, MD USA