Table II.

Studies which found no evidence of the beneficial effects of positive suggestions

Reference	Medical procedure	Suggestion intervention	Result
Block et al. [34]	Various abdominal surgeries	Suggestion tape during general anesthesia	No difference was found between the suggestion and control groups in the frequency of consumption and the dosage of postoperative analgesic and antiemetic drugs; in pyrexia, nauseam and vomiting; in the incidence of other gastrointestinal or urinary complaints; in the levels of pain, anxiety, physiological or psychological recovery; and in the length of hospital stay after the operation
Dawson et al. [35]	Hysterectomy	Suggestion tape during general anesthesia	No difference between the groups in analgesic and antiemetic drug requirement; and in the level of pain, and nausea
Melzack et al. [36]	Gallbladder surgery or hysterectomy	Suggestion tape during general anesthesia	The suggestion and control groups did not differ in their reported pain intensity in the first four postoperative days, and contrary to the expectations control group patients spent in average 17 hours less in the hospital than the suggestion group (p < 0.05)
Blankfield et al. [37]	Coronary artery bypass surgery	Suggestion tape during general anesthesia and after surgery	Time spent in the post-anesthesia care unit (PACU) and in the hospital, the amount of analgesics used, anxiety, depression and recovery scores, daily activity and cardiovascular problems were the same in the control and the suggestion group. None the less half of the patients in the suggestion group claimed that the intervention tape helped them in some way
Van der Laan et al. [38]	Hysterectomy, myomectomy, or gynecologic laparotomy	Suggestion intervention before and after surgery	The groups did not show difference in postoperative morphine consumption, pain intensity, length of hospital stay, and nausea and anxiety scores
Liu et al. [41]	Hysterectomy	Suggestion tape during general anesthesia	No difference was reported between the groups in the length of postoperative pyrexia, subjective pain intensity, the amount of analgesics used, the number of nausea episodes, flatulence, mobility, wound or other complications and length of hospital stay
Boeke et al. [39]	Gallbladder surgery	Suggestion tape during general anesthesia	The suggestion and control groups did not differ in subjective pain intensity, length of hospital stay, level of nausea, subjective wellbeing and in the level of recovery assessed by the medical staff