Planning a clinical trial with allowance for cost and patient recruitment rate.

This paper deals with: (1) estimation of the optimum clinical trial size minimizing the total cost, given types I and II errors, alpha, beta and response rate difference, delta; (2) studying the test performance by calculating the operating characteristic curve in case of available fixed total cost; (3) mapping the future course of the patient recruitment plan by estimating recruitment rate and final intake based on enrollment to date; (4) projecting the recruitment duration and probability of achieving the contracted goal in case the recruitment rate is well established.