DiBenedetti DB, Price MA, Andrews EB. Cognitive interviewing in risk minimization survey development: patient and healthcare professional surveys. Expert Rev Clin Pharmacol. 2013;6(4):369-73.
Espaulella J, Guyer H, Diaz-Escriu F, Mellado-Navas JA, Castells M, Pladevall-Vila M. Nutritional supplementation of elderly hip fracture patients. A randomized, double-blind, placebo-controlled trial. Age Ageing. 2000 Sep;29(5):425-31.