A novel placebo-controlled clinical study design without ethical concerns - the free choice paradigm

All doubled-blinded and placebo-controlled randomized drug trials carry the ethical limitation that up to 50% of patients are treated by an inert placebo pill for a prolonged period of time, and that treatment effects of the drug have to be separated from unspecific (placebo) effects that also occur in the drug arm of the treatment. We propose the "free choice paradigm" (FCP) as an alternative. It allows patients to choose between two pills identical in shape and colour of which one is the drug and the other is the placebo (in a double-blinded fashion), and drug efficacy is assessed as the difference in the number of events (days) one pill is chosen over the other. Advantages as well as disadvantages and limitations of the FCP still need to be assessed, as need the computational statistics to demonstrate superiority of drug over placebo. Ethical limitations are, however, minimized.