When was there ever a blind trial of the effect that modern comprehensive schools actually have?

Such a design is called a double blind trial.

The opposite of a blind trial is an open trial.

Blind trials control all of these by making whatever expectations there are equal for all cases.

Results of a prospective placebo controlled double blind trial.

An eight-week double blind trial involved 20 obese patients.

There are two levels of the treatment, drug, and placebo, administered to male and female patients in a double blind trial.

Two randomized and blinded trials found no benefit in those with osteoporosis-related fractures.

Folic acid blinded trial in identical twins with fragile X syndrome.

Placebos are used to create blind trials.

I worry that this view of blind trials is part of a devaluing of science and knowledge.

Blind trials work like this: Some people are given the medicine or treatment being tested, and others are given the placebo.

Childhood obesity treatment: double blinded trial on dietary fibres (glucomannan) versus placebo.

A double blind trial.

Placebos are most commonly used in blinded trials, where subjects do not know whether they are receiving real or placebo treatment.

Measurements were carried out after the intake of 19.8 g psyllium or placebo in a randomised, crossover, double blind trial.

Randomized placebo-controlled, single blind trial of holy basil leaves in patients with noninsulin-dependent diabetes mellitus.

In any anonymous blind trial of Emin's work she would be very lucky to be given a drawing age of 15yrs, that's how bad it is.

Acetylcysteine is being tested in a double blind trial in Systemic Lupus Erythematosus.

Truth and Consequences One of the first laws of socially responsible deceit is to call it by another name - undercover reporting, a blind trial, a sting.

The benefit noted in the blinded trials could be entirely explained by the placebo effect, therefore casting doubt on the benefit of the procedure for these other subgroups.

In order to separate real responses from psychogenic ones, dummy challenges, with foods that are known not to cause any reaction, are included in the double - blind trials.

I call the paper, 'Being "Nice" to Borderlines: Random Blind Trials of Placedon and Zephyrill.' "

All you can do is be scrupulous, randomize properly, and (if possible) carry out blind or double blind experiments (see What are 'blind' and 'double blind trials'?

However, in drug testing involving blind trials, volunteers are told they may be receiving a placebo; they do not know if they are, but they know they may be.