[1] Univ Missouri, Sch Med, Dept Family & Community Med, Columbia, MO USA
[2] Univ Wisconsin, Sch Med & Publ Hlth, Dept Family Med & Community Hlth, Madison, WI 53706 USA
[3] Univ Minnesota, Dept Family Med & Community Hlth, Minneapolis, MN USA
[4] Dartmouth Med Sch, Dept Community & Family Med, Hanover, NH USA
[5] Queens Univ, Dept Family Med, Kingston, ON, Canada