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Archivos Argentinos de Pediatria Dec 2020
Topics: Ethics, Medical; Humans; Placebo Effect
PubMed: 33231040
DOI: 10.5546/aap.2020.eng.370 -
Drugs of Today (Barcelona, Spain : 1998) Jul 2019The placebo effect is a phenomenon of great scientific interest that affects the response in both inactive and active treatments. It is broadly understood as the product... (Review)
Review
The placebo effect is a phenomenon of great scientific interest that affects the response in both inactive and active treatments. It is broadly understood as the product of a central integration of positive expectations, reward learning and continuous conditioning inducing physiological changes in the brain. The placebo effect is accepted as a phenomenon which can be harnessed in clinical practice. It has emerged that there is not a single neurobiological mechanism involved in placebo responses, but many depending on the underlying disease. Molecular neuroimaging techniques with positron emission tomography and selective radiotracers have been significant in the understanding of the neurobiological systems involved in the placebo effect. The aim of this review was to summarize the key findings relating to the neurobiology behind the placebo effect.
Topics: Brain; Humans; Neurobiology; Placebo Effect; Positron-Emission Tomography
PubMed: 31347615
DOI: 10.1358/dot.2019.55.7.3010575 -
The New England Journal of Medicine Feb 2020
Review
Topics: Conditioning, Psychological; Humans; Hyperalgesia; Nervous System Physiological Phenomena; Nocebo Effect; Placebo Effect
PubMed: 32023375
DOI: 10.1056/NEJMra1907805 -
Trials Jul 2021Contextual effects (i.e., placebo response) refer to all health changes resulting from administering an apparently inactive treatment. In a randomized clinical trial... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Contextual effects (i.e., placebo response) refer to all health changes resulting from administering an apparently inactive treatment. In a randomized clinical trial (RCT), the overall treatment effect (i.e., the post-treatment effect in the intervention group) can be regarded as the true effect of the intervention plus the impact of contextual effects. This meta-research was conducted to examine the average proportion of the overall treatment effect attributable to contextual effects in RCTs across clinical conditions and treatments and explore whether it varies with trial contextual factors.
METHODS
Data was extracted from trials included in the main meta-analysis from the latest update of the Cochrane review on "Placebo interventions for all clinical conditions" (searched from 1966 to March 2008). Only RCTs reported in English having an experimental intervention group, a placebo comparator group, and a no-treatment control group were eligible.
RESULTS
In total, 186 trials (16,655 patients) were included. On average, 54% (0.54, 95%CI 0.46 to 0.64) of the overall treatment effect was attributable to contextual effects. The contextual effects were higher for trials with blinded outcome assessor and concealed allocation. The contextual effects appeared to increase proportional to the placebo effect, lower mean age, and proportion of females.
CONCLUSION
Approximately half of the overall treatment effect in RCTs seems attributable to contextual effects rather than to the specific effect of treatments. As the study did not include all important contextual factors (e.g., patient-provider interaction), the true proportion of contextual effects could differ from the study's results. However, contextual effects should be considered when assessing treatment effects in clinical practice.
TRIAL REGISTRATION
PROSPERO CRD42019130257 . Registered on April 19, 2019.
Topics: Female; Humans; Placebo Effect; Randomized Controlled Trials as Topic
PubMed: 34311793
DOI: 10.1186/s13063-021-05454-8 -
Musculoskeletal Science & Practice Dec 2022While the placebo effect is increasingly recognised as a contributor to treatment effects in clinical practice, the nocebo and other undesirable effects are less well... (Review)
Review
INTRODUCTION
While the placebo effect is increasingly recognised as a contributor to treatment effects in clinical practice, the nocebo and other undesirable effects are less well explored and likely underestimated. In the chiropractic, osteopathy and physiotherapy professions, some aspects of historical models of care may arguably increase the risk of nocebo effects.
PURPOSE
In this masterclass article, clinicians, researchers, and educators are invited to reflect on such possibilities, in an attempt to stimulate research and raise awareness for the mitigation of such undesirable effects.
IMPLICATIONS
This masterclass briefly introduces the nocebo effect and its underlying mechanisms. It then traces the historical development of chiropractic, osteopathy, and physiotherapy, arguing that there was and continues to be an excessive focus on the patient's body. Next, aspects of clinical practice, including communication, the therapeutic relationship, clinical rituals, and the wider social and economic context of practice are examined for their potential to generate nocebo and other undesirable effects. To aid reflection, a model to reflect on clinical practice and individual professions through the 'prism' of nocebo and other undesirable effects is introduced and illustrated. Finally, steps are proposed for how researchers, educators, and practitioners can maximise positive and minimise negative clinical context.
Topics: Humans; Nocebo Effect; Placebo Effect; Physical Therapy Modalities; Communication
PubMed: 36368170
DOI: 10.1016/j.msksp.2022.102677 -
Complementary Therapies in Clinical... Aug 2022Reflexology is a complementary therapy focusing mainly on the application of pressure on the feet, hands and ears. A small but growing evidence base suggests that...
Reflexology is a complementary therapy focusing mainly on the application of pressure on the feet, hands and ears. A small but growing evidence base suggests that positive outcomes can be gained in the management and improvement of symptoms across a range of conditions. Biological plausibility is a key concept in the determination of the usefulness of therapies. Research which tests for safety and efficacy alongside the underpinning mechanism of action are therefore important. This paper explores the potential mechanism of action for the outcomes associated with reflexology treatment as reflected in the current evidence. The influences of therapeutic touch, relaxation, placebo effects and the similarities with other therapeutic methods of structural manipulation are considered. The lack of clarity around the precise definition of reflexology and the challenges of researching the therapy as a treatment tailored to individual need are discussed. A deeper understanding of the mechanism of action for reflexology may help to further develop research into safety and efficacy. Such an understanding may lead to the integration of knowledge which may provide both symptomatic support and longer term preventative health benefits.
Topics: Complementary Therapies; Ear; Foot; Hand; Humans; Massage; Musculoskeletal Manipulations; Placebo Effect; Relaxation Therapy; Therapeutic Touch
PubMed: 35613519
DOI: 10.1016/j.ctcp.2022.101606 -
The Journal of Dermatological Treatment Mar 2021Androgenetic alopecia is a stressful condition for males. Minoxidil 2% and 5% have been FDA approved for treatment of this condition. In literature, all studies have... (Randomized Controlled Trial)
Randomized Controlled Trial
INTRODUCTION
Androgenetic alopecia is a stressful condition for males. Minoxidil 2% and 5% have been FDA approved for treatment of this condition. In literature, all studies have compared minoxidil 5% with 2%. Although other concentrations (2% to 12.5%) are available nowadays, we believe our study is the first to compare 10% versus 5% topical minoxidil in treatment of AGA.
OBJECTIVE
To compare the efficacy and safety of 5% topical minoxidil with 10% topical minoxidil and placebo in AGA treatment.
MATERIALS AND METHODS
36-weeks, double-blinded, placebo-controlled, randomized trial. A total of 90 men with AGA. First group have applied 5% minoxidil solution, second group applied 10% minoxidil solution; or third placebo group. Efficacy was evaluated clinically and trichoscopically.
RESULTS
After 36 weeks of therapy; 5% topical minoxidil (0.47 ± 0.26) (0.59 ± 0.64) was significantly superior to 10% topical minoxidil (0.05 ± 0.13) (0.45 ± 0.74) and placebo (0.01 ± 0.05) (-0.03 ± 0.08) in terms of change from baseline in total vertex and frontal hair mean count respectively. Pull test change to negative in minoxidil 5%: (37%) patients after 6 month treatment, Minoxidil 10% group (37.5%) patients changed and in placebo group all patients after 6 month were the same (0%) change. No reported sexual dysfunction in all three groups.
CONCLUSION
Five percent of topical minoxidil was moderately superior to 10% topical minoxidil and placebo in increasing hair regrowth opposite to the expected, the irritation was marked for 10% topical minoxidil. Psychosocial stress after 10% usage were worsen by the shedding, irritation compared to their high expectation in comparison to 5% usage.
Topics: Administration, Topical; Adult; Alopecia; Double-Blind Method; Hair; Humans; Male; Minoxidil; Patient Satisfaction; Placebo Effect; Treatment Outcome; Young Adult
PubMed: 31403367
DOI: 10.1080/09546634.2019.1654070 -
Annual Review of Pharmacology and... Jan 2024Adverse nocebo responses can cause harm to patients and interfere with treatment adherence and effects in both clinic practice and clinical trials. Nocebo responses... (Review)
Review
Adverse nocebo responses can cause harm to patients and interfere with treatment adherence and effects in both clinic practice and clinical trials. Nocebo responses refer to negative outcomes to active medical treatments in clinical trials or practice that cannot be explained by the treatment's pharmacologic effects. Negative expectancies and nocebo effects are less known than placebo responses. Nocebo effects can be triggered by verbal suggestions, prior negative experiences, observation of others experiencing negative outcomes, and other contextual and environmental factors. As research advances over the years, mechanistic knowledge is accumulating on the neurobiological mechanisms of nocebo effects. This review summarizes studies on different facets of nocebo effects and responses and discusses clinical implications, ethical considerations, and future directions.
Topics: Humans; Nocebo Effect; Placebo Effect
PubMed: 37585661
DOI: 10.1146/annurev-pharmtox-022723-112425 -
International Review of Neurobiology 2020Determinants of placebo effects and placebo response can be considered from multiple intrinsic and extrinsic perspectives. Intrinsic factors may influence the patient... (Review)
Review
Determinants of placebo effects and placebo response can be considered from multiple intrinsic and extrinsic perspectives. Intrinsic factors may influence the patient and the clinician/researcher. Patient expectations and previous experiences are considered two of the major intrinsic determinants of placebo response. Other patient determinants include the neural systems under treatment/study, situational factors and reactions to the environment, and personality traits. Clinician/researcher determinants of placebo response include personality factors such as empathy, perceived expertise, the clinical relationship with the patient, and the clinician's belief in the efficacy of the treatment. Extrinsic determinants include the type of study design, influence of advertising or branding, and forces expressed by the cultural milieu. These determinants do not act in isolation, but rather form a complex interaction that ultimately impacts the promotion or deterrence of the placebo effect in clinical and research settings.
Topics: Anticipation, Psychological; Health Knowledge, Attitudes, Practice; Humans; Personality; Placebo Effect; Placebos; Professional-Patient Relations; Research Design; Signal Transduction
PubMed: 32563291
DOI: 10.1016/bs.irn.2020.03.029 -
American Journal of Epidemiology Jan 2021
Topics: Humans; Causality; Placebo Effect; Research Design
PubMed: 32719871
DOI: 10.1093/aje/kwaa162