From therapeutic trials to current practice

Ideally, there is continuous interaction between clinical reality and the methods of controlled clinical trials. The design of a proper trial ought to reflect the physician's and especially the patient's point of view, and conversely a familiarity with clinical trials improves the methods of daily practice. In other words, every methodological principle is rooted in clinical practice. Some examples are: randomisation (with constructive doubt as its practical equivalent), independence (a healthy mistrust of drug companies), informed consent (sharing uncertainty with patients), type I error (no false optimism after a single trial), type II error (no false pessimism after a single trial), choosing the right measure of outcome (relevance outweighs precision), the intention-to-treat principle (pragmatic analysis), and the dangers of subgroup analysis (the "my-last-patient syndrome").