Adaptive randomization for clinical trials with delayed response

Abstract

Abstract: AIM: To discuss the application condition and evaluate the effect of the adaptive randomization in clinical trials with delayed response.METHODS: The statistical simulations were conducted to evaluate the modified randomized play-the-winner (MRPW) rule and to explore its application condition in clinical trials with delayed response. All the tests were done under circumstances of different effective rates, different levels of rate differences between groups and different delayed levels of response. The proportion of the sample size of the superior group(Group A), the average reduced failure number and the power were also considered during the evaluation.RESULTS: When the rate difference between two groups was small, with relatively low effective rate, different delayed levels had little impact on the effect of MRPW. As effective rate went up, delayed effect on MRPW gradually emerge. When the rate difference between two groups was relatively high, with the increase of delayed time, the weakening tendency of effects on MRPW was obvious. This trend was more obvious in condition of higher effective rate. If the application criterion was set as that the reduction of average reduced failure number should be in the upper limit of 20%, the restriction of delay was less stringent in the condition of lower effective rate, while this restriction was rigorous when effective rates and the difference between effective rates were higher.CONCLUSION: The study extends the application of MRPW in clinical trials with delayed response, which shows that the results of MRPW fit the demand when the delay degree is in some region. According to specific parameters and delayed levels of response in actual clinical trial, we should explore the effect of MRPW to discuss whether to conduct the MRPW in such trial.

Key words: Adaptive randomization, Randomized play-the-winner role, Delayed response

CLC Number:

R311

WEI Yong-yue, XUN Peng-cheng, ZHOU Min-lin, ZHAO Yang, ZHU Jin-jin, YU Hao, CHEN Feng. Adaptive randomization for clinical trials with delayed response[J]. Chinese Journal of Clinical Pharmacology and Therapeutics, 2010, 15(9): 1040-1045.

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