Dean Ornish contirbutes his response to a series of invited essays on the topic “What Scientific Idea is Ready for Retirement?” His choice is the large randomized controlled trial. While I believe his criticism is too one-sided, he does raise some interesting points about the difficulty in using large trials to assess behavioral interventions.
Ornish D. Edge: What Scientific Idea Is Ready for Retirement–Large Randomized Controlled Trials. Excerpt: “It is a commonly held but erroneous belief that a larger study is always more rigorous or definitive than a smaller one, and a randomized controlled trial is always the gold standard . However, there is a growing awareness that size does not always matter and a randomized controlled trial may introduce its own biases. We need more creative experimental designs.” Available at: http://www.edge.org/response-detail/25497.
While we’re at it, take a look at Gerd Gigerenzer’s comment about scientific inference versus statistical rituals and Gary Marcus’s comment about big data. and Bart Kosko’s comment about statistical independence. and Gary Klein’s comment about evidence based medicine. and Chalres Seife’s comment about statistical significance. and Nassim Nicholas Taleb’s comment about the standard deviation and Melanie Swan’s comment on the scientific method and Richard Nisbett’s comment on multiple regression as a means of discovering causality and Adam Alter’s comment on replication as a safety net and Emanuel Derman’s comment on the power of statistics.