Conclusions Due to exploratory design s and high risk of bias , the effectiveness of hypnosis or hypnotherapy in stress reduction remains still unclear .
Background Although hypnosis and hypnotherapy have become more popular in recent years , the evidence for hypnosis to influence perceived stress is unclear .
In this systematic review we search ed and evaluated r and omized clinical studies investigating the effect of hypnosis on perceived stress reduction and coping .
A randomised controlled single-blind trial of the effects of Reiki and positive imagery on well-being and salivary cortisol
The study investigated whether participants who received Reiki  would show greater health and well-being benefits than a group who received no Reiki . A method of blinding participants to Reiki was also tested , where non-contact Reiki or No-Reiki with r and om assignment was given to 35 healthy psychology undergraduates whose attention was absorbed in one of three tasks involving self-hypnosis/relaxation . Participants experienced ten 20-min intervention sessions over a period of two and a half to 12 weeks . Reiki was directed by the experimenter who sat behind the participants as they were absorbed in the tasks . Self-report measures of illness symptoms , mood and sleep were assessed pre-post-intervention as was salivary cortisol . While the Reiki group had a tendency towards a reduction in illness symptoms , a substantive increase was seen in the No-Reiki . The Reiki group also had a near-significant comparative reduction in stress , although they also had significantly higher baseline illness symptoms and stress scores . The Reiki blinding was successful - the groups did not differ statistically in their beliefs regarding group membership . The results are suggestive that the Reiki buffered the substantive decline in health in the course of the academic year seen in the No-Reiki group
Conclusions Due to exploratory design s and high risk of bias , the effectiveness of hypnosis or hypnotherapy in stress reduction remains still unclear .
Background Although hypnosis and hypnotherapy have become more popular in recent years , the evidence for hypnosis to influence perceived stress is unclear .
In this systematic review we search ed and evaluated r and omized clinical studies investigating the effect of hypnosis on perceived stress reduction and coping .