Estrada CA, Unterborn JN, Price J, Thompson D, Gibson L. Judging the effectiveness of clinical pathways for pneumonia: the role of risk adjustment. Eff Clin Pract. 2000 Sep 1;3(5):221-8.
Cann CI, Fried MP, Rothman KJ. Epidemiology of squamous-cell cancer of the head and neck. Otolaryngol Clin N Am. 1985 Aug 1;18(3):367-88.