A Qualitative Systematic Review of Effects of Provider Characteristics and Nonverbal Behavior on Pain, and Placebo and Nocebo Effects

Abstract

Background: Previous research has indicated that the sex, status, and nonverbal behaviors of experimenters or clinicians can contribute to reported pain, and placebo and nocebo effects in patients or research participants. However, no systematic review has been published. Objective: The aim of this study was to investigate the effects of experimenter/clinician characteristics and nonverbal behavior on pain, placebo, and nocebo effects. Methods: Using EmBase, Web of Knowledge, and PubMed databases, several literature searches were conducted to find studies that investigated the effects of the experimenter’s/clinician’s sex, status, and nonverbal behaviors on pain, placebo, and nocebo effects. Results: Thirty-four studies were included, 20 on the effects of characteristics of the experimenter/clinician, 11 on the role of nonverbal behaviors, and 3 on the effects of both nonverbal behaviors and characteristics of experimenters/clinicians on pain and placebo/nocebo effects. There was a tendency for experimenters/clinicians to induce lower pain report in participants of the opposite sex. Furthermore, higher confidence, competence, and professionalism of experimenters/clinicians resulted in lower pain report and higher placebo effects, whereas lower status of experimenters/clinicians such as lower confidence, competence, and professionalism generated higher reported pain and lower placebo effects. Positive nonverbal behaviors (e.g., smiling, strong tone of voice, more eye contact, more leaning toward the patient/participant, and more body gestures) contributed to lower reported pain and higher placebo effects, whereas negative nonverbal behaviors (i.e., no smile, monotonous tone of voice, no eye contact, leaning backward from the participant/patient, and no body gestures) contributed to higher reported pain and nocebo effects. Conclusion: Characteristics and nonverbal behaviors of experimenters/clinicians contribute to the elicitation and modulation of pain, placebo, and nocebo effects.

Time-Dependent Negative Effects of Verbal and Non-verbal Suggestions in Surgical Patients—A Study on Arm Muscle Strength

“…Others have reported delayed recovery from surgery and increased consumption of analgesics (Ulrich, 1984). Our findings are in accordance with observation of non-verbal induction of placebo and nocebo effects (Daniali and Flaten, 2019). This course of a patient subsequently meeting different suggestions is a typical clinical situation in a hospital.…”

Placebo Analgesia, Nocebo Hyperalgesia, and the Cardiovascular System: A Qualitative Systematic Review

“…Thirdly, due to different terms and inconsistent keywords used across studies, access to all relevant studies may have been limited. However, to ensure the inclusion of all relevant studies, we manually reviewed the citation and reference lists of all included studies, as in similar previous SRs (Daniali and Flaten, 2019 ). A fourth limitation is the lack of a thorough report on the method of cardiac data recording as in Aslaksen et al ( 2014 ) or a thorough report on cardiac analysis method as in Roderigo et al ( 2017 ), which hinders a clear conclusion.…”

Premortem Chronic Traumatic Encephalopathy Diagnoses in Professional Football

“…In the context of this cohort, 30 the role of nocebo-based effects on symptoms and disability 42 should not be overlooked. 43 Our findings emphasize the importance of careful clinical assessment of comorbidities and other causes of cognitive decline in former athletes with neurocognitive symptomatology before assuming that CTE is the responsible etiology. The evaluation of former contact and combative sport athletes with cognitive problems should emphasize diagnostic assessment through which treatable conditions are prioritized and addressed, as well as a specialized and careful evaluation of all possible causes of cognitive dysfunction and dementia.…”

“…Such nebulous diagnoses could produce a nocebo effect and trigger mental health challenges, discourage further diagnostic efforts for potentially treatable conditions, and lead to tragic consequences. In the context of this cohort, the role of nocebo‐based effects on symptoms and disability should not be overlooked …”