A randomized clinical trial may include controls in which some of the subjects receive a product which has no active ingredients, referred to as a placebo, e.g. a sugar pill or an injection of normal saline. None of the people in the clinical trial nor the clinical team administering the intervention know who was given the placebo, or the test product, or the best performing existing product. A placebo controlled trial enables researchers to evaluate whether the simple act of being given a pill or an injection has a beneficial effect.