Raghunathan K, Layton JB, Ohnuma T, Shaw AD. Observational research using propensity scores. Adv Chronic Kidney Dis. 2016 Nov;23(6):367-72. doi: 10.1053/j.ackd.2016.11.010
Chirila C, Earnshaw SR, Black L, McDade CL, Roskell NS, Shannon PR, Montorsi F, Andriole GL. Economic analysis: randomized, placebo-controlled clinical trial of dutasteride in men at high risk for prostate cancer. J Cancer Sci Ther. 2011;S3(004). doi: 10.4172/1948-5956.S3-004
Mordin M, Anastassopoulos K, van Breda A, Vallow S, Zhang M, Gargiulo K, Hewitt D, Olson W, Sikirica V. Clinical staff resource use with intravenous patient-controlled analgesia in acute postoperative pain management: results from a multicenter, prospective, observational study. J Perianesth Nurs. 2007 Aug 1;22(4):243-55.