[1] Univ N Carolina, Sch Nursing, 5004 Carrington Hall,Campus Box 7460, Chapel Hill, NC 27599 USA
[2] Univ Calif Irvine, Sue & Bill Gross Sch Nursing, Irvine, CA USA
[3] Penn State Univ, Ross & Carol Nese Coll Nursing, University Pk, PA 16802 USA
[4] Univ Calif Davis, Betty Irene Moore Sch Nursing, Sacramento, CA 95817 USA