McCarney R, Warner J, Iliffe S, Van Haselen R, Griffin M, Fisher P. The Hawthorne Effect: a randomised, controlled trial. BMC Med Res Methodol. 2007;7:30.
Online Statistics Education: An Interactive Multimedia Course of Study - David M. Lane (Rice University). Developed by Rice University (Lead Developer), University of Houston Clear Lake, and Tufts University
Rothwell PM. External validity of randomised controlled trials: "to whom do the results of this trial apply?". Lancet. 2005;365(9453):82-93. Article available to NEOMED library patrons. Access is available upon authentication.
Frenz D, Beattie J. DOO, POO and you: getting on the same page as your patients. Today's Hospitalist [Internet]. 2014 Jul. Available from: http://www.todayshospitalist.com/index.php?b=articles_read&cnt=1901