The more Power the Better

Some researchers have argued that it is dangerous to have too much power. They claim that with too much power, it is easy to find an effect that is statistically significant but not practically significant. For instance, an experiment with 250 subjects per group would be likely to detect a trivial effect. The fallacy in this argument is that competent researchers do not confuse statistical and practical significance. Moreover, if the sample size is large then a confidence interval will reveal how small the effect is.