Table 3 Summary of findings regarding conditions in which placebos are used and/or reasons for using placebos.

Goldberg 1979 [18]

N: In 39 of 43 (91%) patient's pain was an indication. For 36 patients more than one reason was reported; in 51% anxiety; in 47% symptoms suspected not to be organic; in 33% in suspected drug abuse; in 24% as nothing else was helping; in 16% fear of iatrogenic addiction; in 7% concern for patient safety; in 37 of 43 patients receiving placebo (86%) anxiety and emotional problems were seen as prominent; 28% were considered less likeable; 30% more difficult than average; 81% were considered questionable or unreliable.

Goodwin 1999 [19]

Ph/N: 87% of physicians and 97% of registered nurses who had used a placebo in the past had ordered it for a patient requiring more pain medication that thought necessary; 74% and 84% had ordered it in 'problem patients'

Gray 1981 [20]

Ph/N: Conditions: 89% pain (45% patients with regular narcotic analgesia; 34% postoperative; 8% terminally ill); 9% anxiety. More than half of replies indicated that patients describing features such as manipulative, complaining, and histrionic behaviour usually received placebos.

Lange 1981 [21]

Diagnoses in the 88 patients receiving placebo from the 1725 psychiatric patients surveyed: 27% schizophrenia and paranoid symptoms; 27% abuse; 19% depressive psychoses; 14% hysteric syndromes. Symptoms treated with placebo: 40% pain; 29% sleep problems; 8% agitation. Reasons for placebo application: most frequently to cope with a difficult situation and in frequently complaining or disliked patients. Further reasons: other interventions not successful; avoid substance abuse; patients desire for receiving drug treatment.

Classen 1985 [23]

Ph: In patients who demand too many, too powerful or inadequate drugs (50%); psychosomatic complaints (42%); pain (36%); somatic disorders (7%).

Saupe1986 [24]

N: 72% in demanding patients; 78% in patients with so called psychosomatic complaints; 67% requests for pain relief.

Ernst 1997 [27]

N: Probably open-ended question (responses given by placebo users): 19% pain; 11% insomnia; 7% both; 8% anxiety; 5% addiction.

Berger 1999 [28]

Medical interns: Likely to use a placebo in the following circumstances: Suspicion of factitious pain (48%); history of substance abuse (18%); psychiatric illness/psychological component (17%).

Hrobjartsson 2003 [30]

Ph: 226 (45%) respondents provided examples: 90 used various placebos as for treating pain; 86 antibiotics for viral infections; 32 vitamins against fatigue; 28 various placebos for cough and chronic obstructive lung disease. Reported reasons (total sample): follow the wish of the patient and avoid conflicts with patients (70% GPs, 46% hospital clinicians, 42% private specialists); take advantage of the placebo effect (48%, 22%, 32%); avoid discontinuation of other prescriptions (40%, 27%, 18%); avoid telling patients that treatment possibilities are exhausted (36%, 11%, 17%).

Nitzan 2004 [31]

Ph/N: Conditions: The medical conditions for which the placebos were used included anxiety, pain (including abdominal), agitation, vertigo, sleep problems, asthma, contractions in labour, withdrawal from recreational drugs, and angina pectoris (when the blood pressure was too low to allow for vasodilators). Reasons: 43% after 'unjustified' demand of medication; 38% to calm the patient; 38% as analgesic; 28% as diagnostic tool; 23% as adjunctive therapy; 17% for non-specific complaints; 15% to buy time before next regular dosage of medication; 11% to get patient to stop complaining.

Sherman 2007 [33]

Ph: Among placebo users 18% used placebos to calm the patient; 18% as supplemental treatment; 15% after 'unjustified' demand for medication; 13% for non-specific symptoms; 11% after all treatment possibility were exhausted; 6% to control pain; 6% to get the patient stop complaining.

Bernateck 2009 [35]

Ph: Conditions (responses given by placebo users): 76% (65% physicians, 81% nurses) for pain; 59% insomnia (40%, 66%); 12% depressive mood (19%, 10%). Reasons for placebo application: 64% (57%, 66%) patient's request for a drug; 37% (35%, 38%) for calming an anxious patient; 35% (24%, 40%) for reducing drug use; 20% (30%, 16%) for supporting other interventions; 18% (24%, 16%) to treat non-specific symptoms.

Fässler 2009 [37]

Ph: 69% of placebo users report as motive 'to gain therapeutic advantage through the placebo effect'; 64% 'to offer a treatment to patients whose complaints and test results are not attributable to a certain disease'; 63% 'to conform with the requests of the patient'; 51% 'to offer treatment to difficult patients'; 44% 'to offer a treatment option to a patient with an incurable disease'; 37% 'in situations in which standard treatments may burden patients with side effects or are contraindicated'; 31% 'to avoid drug addiction'.