Clinical Trials

■■❚❙❘Chapter 5Patient SelectionBelinda Lees, Dorothea Nitsch, Duolao Wang,and Ameet BakhaiWhen designing a clinical trial, the objective is to select a sampleof patients with the disease or condition under investigation.Consideration should be given to the source of the patients,the investigators who are going to recruit them, disease status,and any ethical issues surrounding participation. A set ofcarefully defined eligibility criteria is essential. This shouldensure that the study findings have ‘external validity’ or, inother words, are generalizable for the treatment of futurepatients with the same disease or condition. In this chapter,we discuss some of the important issues to consider whenselecting patients for clinical trials.47