Groenwold RH, Klungel OH, Altman DJ, van der Graaf Y, Hoes AW, Moons KG, Rivero E, Fortuny J, PROTECT WP2. Adjustment for continuous confounders: an example of how to prevent residual confounding. Can Med Assoc J. 2013 Mar 19;185(5):401-6. doi: 10.1503/cmaj.120592
Ferguson JE3rd, Goyal RK, Raynor MC, Nielsen ME, Pruthi RS, Brown PM, Wallen EM. Cost analysis of robot-assisted laparoscopic versus hand-assisted laparoscopic partial nephrectomy. J Endourol. 2012 Aug;26(8):1030-7.
Huybrechts KF, Rothman KJ, Silliman RA, Brookhart MA, Schneeweiss S. Risk of death and hospital admission for major medical events after initiation of psychotropic medications in older adults admitted to nursing homes. Can Med Assoc J. 2011 Apr 1;183(7):E411-9.