crossover trial


crossover trial

A clinical trial design in which subjects act as their own control and are assigned to receive investigational product and controls in an order determined by randomisations, with a washout period between the two epochs.

crossover trial

A scientific study of a therapeutic agent in which participants are exposed in sequence to the putative cure and subsequently (or previously) to an inactive agent or an agent whose efficacy has been previously established. The participants cross over from one arm of the study to the other and serve as their own control group.

Participants in such trials are usually under the care of a team of physicians and nurses and are closely monitored, often with testing and examinations on a weekly basis. The clinical trial nurse or nurse research specialist has a broad variety of roles, depending on the nature of the investigation. The roles include recruiting and introducing patients to the trial, coordinating their care, gathering data about side effects and tolerance, and, frequently, serving as a principal or collaborative investigator. Trial planning and design, data interpretation and analysis, and assessments of toxicity are all elements of the work. Health insurers and managed care providers may place restrictions on clinical trial coverage. Many states have laws requiring insurers to pay for the routine costs of all or some clinical trials. Patient advocates work with researchers to make sure a clinical trial is relevant, as safe as possible, and accessible to the broadest variety of patients.

Synonym: crossover (2)See also: trial