Affiliation: | 1. Health Partners Research Foundation, Minneapolis, Minnesota, 55440;2. Mayo Clinic and Foundation, Rochester, Minnesota, 55905;3. Brekke Associates, Minneapolis, Minnesota, 55410-2252;1. Health Partners Research Foundation (Solberg, Boyle), Minneapolis, Minnesota; USA;2. University of Minnesota (Davidson), Minnesota, USA;3. Blue Cross and Blue Shield of Minnesota (Alesci, Magnan), St. Paul, Minnesota, USA |