-
Clinical & Experimental Optometry Jan 2002
Topics: Humans; Optometry; Placebo Effect; Randomized Controlled Trials as Topic; Research
PubMed: 11952389
DOI: 10.1111/j.1444-0938.2002.tb03065.x -
Clinical Medicine (London, England) 2006
Topics: Humans; Placebo Effect; Randomized Controlled Trials as Topic
PubMed: 17080884
DOI: 10.7861/clinmedicine.6-5-433 -
Clinical Rheumatology Jul 2017The aims of this study were to determine whether placebo treatment in randomised controlled trials (RCTs) is effective for fibromyalgia and to identify possible... (Meta-Analysis)
Meta-Analysis
The aims of this study were to determine whether placebo treatment in randomised controlled trials (RCTs) is effective for fibromyalgia and to identify possible determinants of the magnitude of any such placebo effect. A systematic literature search was undertaken for RCTs in people with fibromyalgia that included a placebo and/or a no-treatment (observation only or waiting list) control group. Placebo effect size (ES) for pain and other outcomes was measured as the improvement of each outcome from baseline divided by the standard deviation of the change from baseline. This effect was compared with changes in the no-treatment control groups. Meta-analysis was undertaken to combine data from different studies. Subgroup analysis was conducted to identify possible determinants of the placebo ES. A total of 3912 studies were identified from the literature search. After scrutiny, 229 trials met the inclusion criteria. Participants who received placebo in the RCTs experienced significantly better improvements in pain, fatigue, sleep quality, physical function, and other main outcomes than those receiving no treatment. The ES of placebo for pain relief was clinically moderate (0.53, 95%CI 0.48 to 0.57). The ES increased with increasing strength of the active treatment, increasing participant age and higher baseline pain severity, but decreased in RCTS with more women and with longer duration of fibromyalgia. In addition, placebo treatment in RCTs is effective in fibromyalgia. A number of factors (expected strength of treatment, age, gender, disease duration) appear to influence the magnitude of the placebo effect in this condition.
Topics: Fibromyalgia; Humans; Pain Management; Placebo Effect
PubMed: 28299460
DOI: 10.1007/s10067-017-3595-8 -
European Journal of Sport Science Apr 2020
Topics: Exercise; Humans; Placebo Effect; Research Design; Sports
PubMed: 32299310
DOI: 10.1080/17461391.2020.1757682 -
Clinical Medicine (London, England) 2003
Topics: Humans; Placebo Effect; Practice Patterns, Physicians'
PubMed: 14601932
DOI: 10.7861/clinmedicine.3-5-397 -
Radiology Jun 2011Our interpretation of the evidence for vertebroplasty has distinctive implications for clinical practice and health policy.
Our interpretation of the evidence for vertebroplasty has distinctive implications for clinical practice and health policy.
Topics: Bone Cements; Humans; Outcome Assessment, Health Care; Pain Measurement; Placebo Effect; Randomized Controlled Trials as Topic; Spinal Fractures; Vertebroplasty
PubMed: 21602500
DOI: 10.1148/radiol.11102412 -
Schmerz (Berlin, Germany) Jun 2022Preoperative treatment expectations have a significant influence on postoperative pain and treatment outcomes. Positive expectations are an important mechanism of the... (Review)
Review
BACKGROUND
Preoperative treatment expectations have a significant influence on postoperative pain and treatment outcomes. Positive expectations are an important mechanism of the placebo effect and negative expectations are an important mechanism of the nocebo effect.
OBJECTIVES
What is the influence of treatment expectations, how are they assessed in the clinical setting, and how can the findings be implemented in clinical practice?
METHODS
A literature search was performed using the keywords "expectation" AND ("postoperative" OR "surgery"). All English and German articles were selected. In addition, the bibliographies of the articles found were examined and incorporated.
RESULTS
A total of 158 articles were found, 49 of which investigate expectations and include postoperative treatment outcomes. Most articles investigate expectations only at baseline to ensure that groups do not differ preoperatively. The studies that prospectively examine the influence of expectations apply very different measurement methods to investigate expectancy constructs. Thus, comparison across studies is difficult. There are few studies examining whether and how expectations can be influenced perioperatively, and who developed practice-relevant interventions to change them.
CONCLUSION
Valid and reliable measurement tools should be applied in clinical trials for a more robust investigation of treatment expectations. Further studies should address possible intervention options so that treatment expectations can also be incorporated into standard clinical care.
Topics: Humans; Motivation; Pain, Postoperative; Placebo Effect; Treatment Outcome
PubMed: 34459995
DOI: 10.1007/s00482-021-00575-0 -
Journal of Oral Rehabilitation May 2022Evidence for the nocebo effect, a phenomenon characterised by suboptimal treatment efficacy, worsening of symptoms, or the occurrence of adverse events caused by an... (Review)
Review
BACKGROUND
Evidence for the nocebo effect, a phenomenon characterised by suboptimal treatment efficacy, worsening of symptoms, or the occurrence of adverse events caused by an individual's negative treatment expectations, is growing across a multitude of medical fields. However, little attention has been paid to patients' negative expectations and the nocebo effect within dentistry.
AIM
This review summarises essential evidence of the nocebo phenomenon especially in relation to pain and drug administration. Subsequently, an overview of the current evidence of the nocebo phenomenon in the dental field is presented.
METHODS
A PubMed search was performed using keywords related to "nocebo," "placebo," "expectations," and "dentistry." In addition to the articles selected from the search, placebo/nocebo researchers and dental researchers added important references from their respective fields.
RESULTS
Although research on the nocebo effect in dentistry is limited, available current evidence suggests that the factors, which is related to the nocebo effect are likely to play a role in dental practice.
CONCLUSION
Preliminary evidence from the review warrants further investigation into the nocebo effect in dentistry. Finally, based on the general knowledge of the nocebo effect, the review indicates fruitful arrays of research into the nocebo effect in dentistry.
Topics: Dentistry; Humans; Nocebo Effect; Placebo Effect; Treatment Outcome
PubMed: 35043415
DOI: 10.1111/joor.13306 -
PloS One 2017The placebo effect is usually studied in clinical settings for decreasing negative symptoms such as pain, depression and anxiety. There is interest in exploring the...
BACKGROUND
The placebo effect is usually studied in clinical settings for decreasing negative symptoms such as pain, depression and anxiety. There is interest in exploring the placebo effect also outside the clinic, for enhancing positive aspects of performance or cognition. Several studies indicate that placebo can enhance cognitive abilities including memory, implicit learning and general knowledge. Here, we ask whether placebo can enhance creativity, an important aspect of human cognition.
METHODS
Subjects were randomly assigned to a control group who smelled and rated an odorant (n = 45), and a placebo group who were treated identically but were also told that the odorant increases creativity and reduces inhibitions (n = 45). Subjects completed a recently developed automated test for creativity, the creative foraging game (CFG), and a randomly chosen subset (n = 57) also completed two manual standardized creativity tests, the alternate uses test (AUT) and the Torrance test (TTCT). In all three tests, participants were asked to create as many original solutions and were scored for originality, flexibility and fluency.
RESULTS
The placebo group showed higher originality than the control group both in the CFG (p<0.04, effect size = 0.5) and in the AUT (p<0.05, effect size = 0.4), but not in the Torrance test. The placebo group also found more shapes outside of the standard categories found by a set of 100 CFG players in a previous study, a feature termed out-of-the-boxness (p<0.01, effect size = 0.6).
CONCLUSIONS
The findings indicate that placebo can enhance the originality aspect of creativity. This strengthens the view that placebo can be used not only to reduce negative clinical symptoms, but also to enhance positive aspects of cognition. Furthermore, we find that the impact of placebo on creativity can be tested by CFG, which can quantify multiple aspects of creative search without need for manual coding. This approach opens the way to explore the behavioral and neural mechanisms by which placebo might amplify creativity.
Topics: Cognition; Creativity; Humans; Odorants; Placebo Effect; Pliability; Thinking
PubMed: 28892513
DOI: 10.1371/journal.pone.0182466 -
Wiener Klinische Wochenschrift May 2020The history of medicine and the history of placebo are closely intertwined. To understand placebo and its effects this article gives a brief overview about its history,... (Review)
Review
The history of medicine and the history of placebo are closely intertwined. To understand placebo and its effects this article gives a brief overview about its history, the possible mechanisms of action and its counterpart, nocebo.The Catholic Church used placebo around the sixteenth century for the separation from real and incorrect exorcisms, but it needed Henry Beecher during World War II to quantify the placebo effect as control arm in well-designed studies.Until today the different mechanisms of action of placebo remain poorly researched. Understanding them would allow its effect to be modulated to better serve in research and clinical settings. Expectation, psychosocial context and conditioning play a significant role in the effect size and amplitude.The counterpart, nocebo, is even less investigated, even it is commonly observed as adverse effects during medical treatments.Conclusion: Placebo and nocebo are both underestimated and underresearched in their value. Through further investigation doctors could strengthen the placebo response and prevent adverse effects to help their patients at low cost. These techniques would benefit the patient-doctor relationship, which is the alter of a trust-based successful therapy.
Topics: Drug-Related Side Effects and Adverse Reactions; Humans; Male; Nocebo Effect; Pain; Physician-Patient Relations; Placebo Effect
PubMed: 32211987
DOI: 10.1007/s00508-020-01626-9