1 Institute for Health Policy Studies, Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, California, USA.
2 School of Public Health, Oregon Health & Science University and Portland State University (OHSU-PSU), Portland, Oregon, USA.
3 Kaiser Permanente Center for Health Research, Portland, Oregon, USA.
4 OCHIN, Inc., Portland, Oregon, USA.
5 Department of Family Medicine, School of Medicine, Oregon Health & Science University, Portland, Oregon, USA.