Abstract:
Fixed sample clinical trials involve humans that are accumulated over a considerably large period of time in order to achieve the pre-specified sample size calculated prior to the study. These designs are somewhat impractical as they do not address economical and some ethical issues such as the decisions are made using a greater number of patients. Thus, for the reason being one of economical and ethical, sequential designs come into practice. At interim inspection, sequential designs either stop or continue. These usually have lesser number of patients, leading to saving in cost and time while improving ethical issues.
