Double blind

Refer to a clinical trial or experiment in which neither the subject nor the researcher knows which treatment any particular subject is receiving.

In social psychology, a situation characteristic of the relationship in the families that produce schizophrenics. The child is punished for the expression of affection and simultaneously blamed for not expressing it.

A method that evaluates the effectiveness of a treatment or compares two treatments. In this type of trial, half the people receive the treatment of interest, while the other half receive a control treatment — often a placebo. The goal is to discover in an unbiased way whether a treatment is effective. A double-blind study is the most rigorous type of clinical research, because neither the people in the study nor the researchers themselves know which treatment a person is receiving. In addition to  reducing the risk of bias, the double blind method can also eliminate the placebo effect, which is a positive or negative response to a treatment resulting from a person’s expectations rather than from a person’s expectations rather than from any real physical or chemical effect.

Cleansing the vagina by flushing it with water or chemicals. Douching is almost never recommended because the natural cleansing process of the vagina is adequate, and douching can facilitate the transport of infectious organisms into the uterus and irritate the vagina. Douching is not an effective method of birth control.

To a method, study, or clinical trial in which neither the subject nor the investigator knows what treatment or medication, if any, the subject receives. A double-blinded study attempts to eliminate observer and subject bias.