Clinical Trial methodology: How do you know who's right? #health20

What is the right organization of a clinical trial: Double blind? But what about ethics? what about cost and time?  PatientsLikeMe published an observational trial on Lithium in ALS disease, because in 2008 a small Italian study predicted hope through this treatment and so PatientsLikeMe decided to compare patients taking lithium with those not taking it. They unfortunately found no difference, as did an academic study published subsequently in the Lancet, taking more time and resources to do so. So, who's right, and how do you know? Patient-professional communication must create errors through the added transmission of information and that self-observational studies must create other error. But it just seems that of all of the approaches, the patient community one must be the closes to reality and the most ethical, no?