Key points are not available for this paper at this time.
1Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA. Correspondence: Peter D.R. Higgins, Department of Internal Medicine, University of Michigan Medical School, 3906 Taubman Center, 1150 West Medical Center Drive, SPC 5682, Ann Arbor, Michigan 48109, USA. E-mail: email protected
Waljee et al. (2010) studied this question.