Braid later acknowledged that the hypnotic induction technique was not necessary in every case, and subsequent researchers have generally found that on average it contributes less than previously expected to the effect of hypnotic suggestions. Variations and alternatives to the original hypnotic induction techniques were subsequently developed. However, this method is still considered authoritative. In 1941, Robert White wrote: "It can be safely stated that nine out of ten hypnotic techniques call for reclining posture, muscular relaxation, and optical fixation followed by eye closure."
Hypnosis is not a psychotherapeutic treatment or a form of psychotherapy, but rather a tool or procedure that helps facilitate various types of therapies and medical or psychological treatments. Only trained health care providers certified in clinical hypnosis can decide, with their patient, if hypnosis should be used along with other treatments. As with psychotherapy, the length of hypnosis treatment varies, depending on the complexity of the problem.