Candrilli SD, Davis KL, Iyer S. Impact of constipation on opioid use patterns, health care resource utilization, and costs in cancer patients on opioid therapy. J Pain Palliat Care Pharmacother. 2009 Sep 1;23(3):231-41.
Rothman KJ, Arellano F. Elevating the level of scientific discourse. Int J Occup Environ Health. 2005 Sep 1;11(3):327-8.