Adaptive clinical trialsCombination functionsConditional error functionsSample size re-estimationTwo-stage methodsAdaptive clinical trials are becoming very popular because of their flexibility in allowing mid-stream changes of sample size, endpoints, populations, etc. At the same time, they have been ...
Mehta CR. Sample size re-estimation for confirmatory clinical trials. In Chapter 4 of Designs for Clinical Trials, Harrington D (ed.). Springer: New York, 2012; 81-108.Mehta CR. Sample size reestimation for confirmatory clinical trials. In: Harrington D (ed). Designs for Clinical Trials: ...
Sample size re-estimation for survival data in clinical trials with an adaptive design. Pharmaceutical Statistics, 10(4):325-331, 2011. ISSN 1539-1612. doi: 10.1002/pst.469. URL http://dx.doi.org/10.1002/pst.469.KanaeTogo, ManabuIwasaki. (2011) Sample size re-estimation for survival data...
The effect size may come from prior trials, from literature review, or quite often from the best guess by the investigator.doi:10.1007/978-1-4757-3466-9_15Wenping WangAndreas KrauseSpringer New YorkGould AL, Shih WJ. "Sample size re-estimation...
What are the advantages & disadvantages of unblinded sample size re-estimation in clinical trials? Let us quickly examine them and what they mean for you. Adaptive trials are any trial where a change or decision is made to a trial while the trial is still on-going. It is said that ...
A sample size justification should be given for all clinical investigations. However, sometimes the objective of a trial is to estimate an effect with a view to planning a later definitive study. This paper describes the calculations for designing studies where one wishes to adopt an estimation ap...
Sample size re-estimationSample size reassessment (SSR) is an increasingly popular strategy for designing and conducting clinical trials. In particular, SSR based on updating the variance estimate is a prudent practice accepted by the regulatory authorities to assure adequate power for a study. Since...
The estimation step in the E + M approach may be able to generate a flatter tail probability curve, and this may increase the significance level of a test and finally lead to a possible power gain. Shan et al. [89] were the first to extend the E + M approach for the sample size ...
Q [17]. The error curve is the average of 10 trials, and the standard deviations are shown by vertical bars. Note that the above error estimation is based on the holdout method, in which design and test samples are independent so that the error becomes larger than the Bayes error (1.9...
, which is described in Section 11.10.3. A Probabilistic Measure of Effect Size Yet another useful measure of effect size is p=P(X1<X2), the probability that a randomly sampled observation from the first group is less than a randomly sampled observation from the second group. Estimation of...