Wood D, Kosa K, Brown D, Ehrlich OG, Higgins PDR, Heller C. Preferences of adult patients with inflammatory bowel disease for attributes of clinical trials: evidence from a choice-based conjoint analysis. Crohns Colitis 360. 2020 Jan;2(1). doi: 10.1093/crocol/otz048
Edwards PET, Parsons GR, Myers KH. The economic value of viewing migratory shorebirds on the Delaware Bay: an application of the single-site travel cost model using on-site data. Hum Dimens Wildl. 2011;16(6):435-44. doi: 10.1080/10871209.2011.608180
Michels KB, Rothman KJ. Update on unethical use of placebos in randomised trials. Bioethics. 2003 Apr;17(2):188-204.