Table 2.
Studies investigating the role of the experimenter/clinician characteristics (sex and status).
| Study | Design | N (Female) | Sample | Type of provider | Characteristics | Target outcome | Result |
|---|---|---|---|---|---|---|---|
| Egbert et al. (46) | Between subjects | 97 (63) | Abdominal surgery patients | Clinicians | Status (confidence) | Narcotic usage, physical and emotional status, postoperative pain intensity | Confident clinicians induced less postoperative narcotics and a better physical and emotional condition. |
| Otto and Dougher (47) | Between subjects | 80 (40) | Healthy participants | Experimenters (2 M and 2 F) | Experimenter sex | Pain intensity | No significant effect of experimenter sex |
| Levine and De Simone (19) | Mixed design | 68 (33) | Healthy participants | Experimenters (1 M and 1 F) | Experimenter sex | Pain intensity | Female experimenters induced lower pain intensity in male subjects. |
| Feine et al. (48) | Between subjects | 20 (20) | Healthy participants | Experimenters (1 F and 1 M) | Experimenter sex | Pain intensity | No significant effect |
| Bush et al. (49) | Between subjects | 47 (24) | Orofacial pain patients | Experimenters (1 F and 1 M) | Experimenter sex | Pain intensity | No significant effect |
| Fillingim et al. (50) | Between subjects | 209 (117) | Healthy participants | Experimenters (1 M and 1 F) | Experimenter and participant sex | Pain thresholds | Female experimenters induced higher pain thresholds in both male and female subjects. |
| Carter et al. (51) | Between subjects | 80 (40) | Healthy participants | Experimenters (not reported) | Experimenter sex | Pain tolerance, electrocardiogram | Female experimenters induced lower electromyogram activity and higher pain tolerance in male and female subjects. |
| Kállai et al. (22) | Mixed design | 160 (80) | Healthy participants | Experimenters (4 M and 4 F) | Status (professional or informal) Experimenter sex |
Pain threshold, pain intensity, pain tolerance | Professional experimenters generated higher pain tolerance in participants. Experimenters induced higher pain tolerance in an opposite sex participant. Female experimenters induced higher pain intensity in male and female subjects. |
| Thorn et al. (52) | Correlation | 219 (129) | Healthy participants | Experimenters (1 M and 1 F) | Experimenter sex | Pain intensity and tolerance | No significant effects. |
| Essick et al. (53) | Between subjects | 34 (17) | Healthy participants | Experimenters (1 M and 1 F) | Experimenter sex | Pain sensitivity | No significant effect. |
| Gijsbers and Nicholson (54) | Between subjects | 64 (32) | Healthy participants | Experimenters (1 M and 1 F) | Experimenter gender | Pain threshold | Female experimenters induced higher pain thresholds in male subjects. |
| Campbell et al. (26) | Between subjects | 117 (117) | Healthy participants | Experimenters | Status (university professor or a graduate assistant) | Blood pressure response, pain tolerance, and unpleasantness | Professors generated higher blood pressure responsivity, higher pain tolerance, and lower pain unpleasantness in subjects. |
| Aslaksen et al. (25) | Mixed design | 64 (32) | Healthy participants | Experimenters (3 M and 3 F) | Experimenter and participants gender | Pain intensity, heart rate, and skin conductance | Female experimenters induced lower pain reports in male subjects. |
| Williams et al. (55) | Correlation | 70 (41) | Low back pain patients | Clinicians | Status (a clinician or an assistant) | Pain intensity recollection after an injection | Clinicians generated recalled-pain ratings in patients that correlated the ratings presented following the procedure. Assistants generated higher pain ratings than their original ratings. |
| Aslaksen and Flaten (56) | Within subjects | 63 (32) | Healthy participants | Experimenters (4 M and 4 F) | Experimenter gender | Pain intensity, placebo, stress, arousal, mood | Male experimenters induced higher placebo responses in male subjects. |
| Kaptchuk et al. (57) | Between subjects | 262 (199) | Patients with IBS | Clinicians | Status (a placebo acupuncture augmented by confidence VS a placebo acupuncture alone—limited—and a waiting list) | Placebo, global improvement, adequate relief, symptom severity, quality of life | Confident clinicians generated higher global improvement, adequate relief of symptoms, better quality of life, and lower symptom severity scores in participants. |
| Weimer et al. (58) | Between subjects | 64 (32) | Healthy participants | Experimenters (1 M and 1 F) | Experimenter sex | Placebo, nausea | No interaction between experimenter sex and placebo responses. |
| Vigil et al. (59) | Mixed design | 352 (169) | Healthy participants | Experimenters (7 M and 7 F and 1 T) | Experimenter gender (and a transgendered experimenter with a feminine status), participant gender | Pain intensity | Male experimenters induced lower pain intensity in both male and female subjects. Transgendered experimenters induced higher pain intensity in female subjects. |
| Vigil and Alcock (60) | Correlation | 199 (86) | Pain patients | Clinicians (not reported) | Experimenter gender | Pain intensity | Both sex patients presented higher pain levels to female clinicians. |
| Sorge et al. (61) | Mixed design | – | Mice | Experimenters (4 F and 4 M) | Experimenter sex | Facial grimacing as a pain behavior | Male experimenters induced less pain behaviors and more pain inhibition in rodents. |
| Vigil et al. (62) | Mixed design | 132 (132) | Menstrual Pain patients | Clinicians (12 M and 7 F) | Clinician sex | Pain tolerance | Male clinicians induced higher pain tolerance in female patients. |
| Modić Stanke and Ivanec (27) | Mixed design | 96 (69) | Healthy participants | Experimenters | Status (either a professor or a student) | Pain threshold | Professors generated higher pain thresholds in participants. Status influenced males more. |
| Howe et al. (44) | Between subjects | 160 (80) | Healthy Participants | Experimenters | Status (high or low competence) | Placebo and nocebo effects (positive and negative expectations) | Competent experimenters enhanced the effects of positive expectations about a placebo cream on allergic responses. |
Just for studies in which the effects of experimenter’s/clinician’s sex were investigated, the number of providers is presented; however, some studies have not reported this number. F, females; M, Males; T, transgendered; IBS, irritable bowel syndrome.