ABSTRACT
A cancer clinical trial is a planned experiment involving cancer patients. Each trial is based on a limited number of patients who satisfy certain study inclusion or exclusion criteria. Cancer clinical trials study the toxicity and efficacy of experimental cancer therapies through four phases of clinical trials, designated phase 1 to 4. Many aspects must be considered when designing a clinical trial. These include the idea for improving treatment, the study objectives, specific hypotheses, the treatment plan, patient eligibility criteria, the method of randomization and blinding, the sample size calculation and statistical analysis plan (ASP), protocol development, database issues, and trial monitoring for safety and ethics considerations. The research questions to be addressed in a clinical trial are summarized in the study objectives, which are classified as primary objectives, secondary objectives, and exploratory objectives according to the importance of the research questions. The study protocol must specify clearly the statistical considerations relating to the trial design and analysis plan.
