[1] Univ Wisconsin, Ctr Hlth Enhancement Syst Studies, Madison, WI 53706 USA
[2] Univ Wisconsin, Sch Journalism & Mass Commun, Madison, WI 53706 USA
[3] Univ Georgia, Dept Telecommun, Athens, GA 30602 USA
[4] Univ Minnesota, Dept Genet Cell Biol & Dev, Minneapolis, MN 55455 USA