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Pipaliya RM, Duckett KA, Monaghan NP, Miller EM, Young G, Brennan EA, Nguyen SA, Soler ZM, Schlosser RJ. The placebo effect in randomized-controlled trials of medical treatments for chronic rhinosinusitis: A systematic review and meta-analysis. Int Forum Allergy Rhinol 2024; 14:695-710. [PMID: 37985206 DOI: 10.1002/alr.23302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 10/12/2023] [Accepted: 11/06/2023] [Indexed: 11/22/2023]
Abstract
BACKGROUND The placebo effect observed in clinical trials evaluating medical treatments for chronic rhinosinusitis (CRS) is not well understood. This systematic review and meta-analysis sought to characterize the placebo effect present within CRS outcomes. METHODS A systematic review of PubMed, Scopus, and Cumulated Index in Nursing and Allied Health Nursing (CINAHL) was performed. Randomized controlled trials (RCTs) evaluating medical treatments for CRS versus placebo were included. We assessed patient-reported (sino-nasal outcome test 22 [SNOT-22], nasal obstruction, sense of smell, nasal obstruction visual analogue score [VAS], sense of smell VAS, anterior rhinorrhea, and postnasal drip) and objective (Lund-Mackay Computed tomography (CT) score, peak nasal inspiratory flow [PNIF], nasal polyp scores, 40-item Smell Identification Test, serum IgE, and blood eosinophil levels) outcomes. RESULTS Twenty-one RCTs were included, comprising 1437 patients (mean age 49.2 years). Biologics were the most common treatment investigated (n = 9). Eleven studies administered background steroids along with placebo. Following placebo administration, multiple patient-reported outcomes significantly decreased, including SNOT-22 (mean difference -9.49, 95% confidence interval [CI] [-11.26, -7.73]), nasal obstruction (-0.33 [-0.54, -0.13]), sense of smell (-0.22 [-0.33, -0.11]), nasal obstruction VAS (-2.47 [-2.87, -2.06]), and loss of smell VAS (-2.31 [-4.14, -0.47]) scores. For objective measures, significant changes occurred in Lund-Mackay CT score (-0.82, [-1.48, -0.16]) and PNIF (4.70, [4.76, 24.64]) with placebo. Placebo arms had the greatest impact when no background medications were used. CONCLUSIONS Placebo treatments have a statistically and potentially clinically significant effect on patient-reported and some objective CRS outcomes. Further investigation is required to fully understand placebo effect, which could improve assessment of RCTs and impact patient care.
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Affiliation(s)
- Royal M Pipaliya
- Department of Otolaryngology-Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Kelsey A Duckett
- Department of Otolaryngology-Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Neil P Monaghan
- Department of Otolaryngology-Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Emma Marin Miller
- Department of Otolaryngology-Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Gabrielle Young
- Department of Otolaryngology-Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Emily A Brennan
- MUSC Libraries, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Shaun A Nguyen
- Department of Otolaryngology-Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Zachary M Soler
- Department of Otolaryngology-Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Rodney J Schlosser
- Department of Otolaryngology-Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
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Goldenholz DM, Goldenholz EB, Kaptchuk TJ. Quantifying and controlling the impact of regression to the mean on randomized controlled trials in epilepsy. Epilepsia 2023; 64:2635-2643. [PMID: 37505116 PMCID: PMC10592227 DOI: 10.1111/epi.17730] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 07/29/2023]
Abstract
OBJECTIVE Randomized controlled trials (RCTs) in epilepsy for drug treatments are plagued by high costs. One potential remedy is to reduce placebo response via better control over regression to the mean (RTM). Here, RTM represents an initial observed seizure rate higher than the long-term average, which gradually settles closer to the average, resulting in apparent response to treatment. This study used simulation to clarify the relationship between eligibility criteria and RTM. METHODS Using a statistically realistic seizure diary simulator, the impact of RTM on placebo response and trial efficacy was explored by varying eligibility criteria for a traditional treatment phase II/III RCT for drug-resistant epilepsy. RESULTS When the baseline period was included in the eligibility criteria, increasingly larger fractions of RTM were observed (25%-47% vs. 23%-25%). Higher fractions of RTM corresponded with higher expected placebo responses (50% responder rate [RR50]: 2%-9% vs. 0%-8%) and lower statistical efficacy (RR50: 47%-67% vs. 47%-81%). The exclusion of baseline from eligibility criteria was shown to decrease the number of patients needed by roughly 30%. SIGNIFICANCE The manipulation of eligibility criteria for RCTs has a predictable and important impact on RTM, and therefore on placebo response; the difference between drug and placebo was more easily detected. This in turn impacts trial efficacy and therefore cost. This study found dramatic improvements in efficacy and cost when baseline was not included in eligibility.
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Affiliation(s)
| | | | - Ted J Kaptchuk
- Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
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Alon Y, Azriel O, Pine DS, Bar-Haim Y. A randomized controlled trial of supervised remotely-delivered attention bias modification for posttraumatic stress disorder. Psychol Med 2023; 53:3601-3610. [PMID: 35132952 PMCID: PMC10248784 DOI: 10.1017/s003329172200023x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 01/03/2022] [Accepted: 01/17/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Many individuals with posttraumatic stress disorder (PTSD) have limited access to first-line treatments, warranting the development of remotely-delivered treatments. Attention bias modification (ABM), targeting perturbed threat-related attentional patterns, shows promise when delivered in-person. However, previous studies found ABM to be ineffective when delivered remotely. Randomized clinical trials usually applied two variations of ABM: ABM away from threat or attention control training (ACT) balancing attention between threat-related and neutral stimuli. We tested remotely-delivered ACT/ABM with tighter supervision and video-based interactions that resemble in-clinic protocols. We expected to replicate the results of in-clinic trials, in which ACT outperformed ABM for PTSD. METHODS In this double-blinded, parallel-group randomized controlled trial, 60 patients diagnosed with PTSD were randomized (ABM n = 30; ACT n = 30). Patients performed eight bi-weekly remotely-delivered supervised ABM/ACT sessions. Symptoms were assessed pre- and post-treatment with Clinician-Administered PTSD Scale 5 (CAPS-5) severity score and PTSD diagnosis as the primary outcomes. Current depressive episode, current anxiety-related comorbidity, and time elapsed since the trauma were examined as potential moderators of treatment outcome. RESULTS Significant decrease in CAPS-5 severity scores and PTSD diagnosis was observed following both ACT and ABM with no between-group difference. Patients without depression or whose trauma occurred more recently had greater symptom reduction in the ACT than the ABM group. CONCLUSIONS Contrary to our expectation, symptoms decreased similarly following ACT and ABM. Moderator analyses suggest advantage for ACT in non-depressed patients and patients whose trauma occurred more recently. Further refinements in remotely-delivered ABM/ACT may be needed.
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Affiliation(s)
- Yaron Alon
- School of Psychological Sciences, Tel-Aviv University, Tel Aviv-Yafo, Israel
| | - Omer Azriel
- School of Psychological Sciences, Tel-Aviv University, Tel Aviv-Yafo, Israel
| | - Daniel S. Pine
- Section on Developmental Affective Neuroscience, National Institute of Mental Health, Bethesda, MD, USA
| | - Yair Bar-Haim
- School of Psychological Sciences, Tel-Aviv University, Tel Aviv-Yafo, Israel
- Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv-Yafo, Israel
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Blokland A. Can placebo or nocebo pills improve or impair cognition performance? Hum Psychopharmacol 2023; 38:e2869. [PMID: 37140377 DOI: 10.1002/hup.2869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 03/24/2023] [Accepted: 03/28/2023] [Indexed: 05/05/2023]
Abstract
OBJECTIVE Although the placebo effect is well known to affect many behaviors, the effects on cognitive performance are less well investigated. METHODS In this study, the effects of a placebo and a nocebo manipulation on cognitive performance was investigated in healthy young participants in an unblinded between-subjects study. In addition, the participants were asked about their subjective experience in the placebo and nocebo condition. RESULTS The data suggested that the placebo condition induced the feeling of being more attentive and more motivated and the nocebo condition induced a feeling of being less attentive and alert and that they performed less well than normal. However, no placebo or nocebo effects were found on the actual performance on word learning, working memory, Tower of London task, or spatial pattern separation. CONCLUSIONS These findings further support the notion that placebo or nocebo effects are not likely to occur in young healthy volunteers. However, other studies suggest that placebo effects can be found in implicit memory tasks and in participants with memory problems. Further placebo/nocebo studies are indicated using different experimental designs and different populations in order to better understand the placebo effect on cognitive performance.
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Affiliation(s)
- Arjan Blokland
- Faculty of Psychology and Neuroscience, Department of Neuropsychology & Psychopharmacology. EURON, Maastricht University, Maastricht, The Netherlands
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5
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Anheyer D, Bugaj TJ, Lüdtke R, Appelbaum S, Trübel H, Ostermann T. No Placebo Effect beyond Regression to the Mean on the Six Minute Walk Test in Pulmonary Arterial Hypertension Trials. Int J Mol Sci 2023; 24:ijms24021069. [PMID: 36674584 PMCID: PMC9865257 DOI: 10.3390/ijms24021069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 01/09/2023] Open
Abstract
In drug studies, patients are often included when the disease activity is high. This will make any treatment appear to lessen disease activity, although the improvement is biased by selection. This effect is known as regression towards the mean (RTM). We aimed at investigating drug trials in Pulmonary Arterial Hypertension (PAH) using the 6-minute walking distance test (6MWD) as a primary outcome for the phenomenon of RTM. An existing registry of 43 open label studies and 23 randomized controlled trials conducted between 1990 and 2009 was used as the data source. Data analysis was carried out for 18 randomized controlled trials (RCTs) and 24 open label studies out of this registry. Data were analyzed for verum and placebo arms of the RCTs separately, as well as for the open label arms. In the verum arms, the overall effect given as 33.2 m (95% CI: 25.7; 40.6]); 6MWD was slightly lower than the effect in the observational studies, with 44.6 m (95% CI: [25.4; 63.8]). After studying and interpreting the data, we found that regression towards the mean plays only a minor role in PAH studies. In particular, placebo effects in the RCTs were negligibly small, with a mean 6MWD of -2.5 m (95% CI: [-9.8; 4.7]) in the placebo arm. Therefore, our analysis indicates that results of non-randomized observational studies can be regarded as valid tools for gaining valid clinical effects in patients with PAH.
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Affiliation(s)
- Dennis Anheyer
- Department for Psychology and Psychotherapy, Witten/Herdecke University, 58458 Witten, Germany
- Institute for General Practice and Interprofessional Care, University Hospital Tübingen, 72076 Tübingen, Germany
| | - Till Johannes Bugaj
- Department of General Internal Medicine and Psychosomatics, University of Heidelberg, Medical Hospital, 69120 Heidelberg, Germany
| | | | - Sebastian Appelbaum
- Department for Psychology and Psychotherapy, Witten/Herdecke University, 58458 Witten, Germany
| | - Hubert Trübel
- Department for Medicine, Witten/Herdecke University, 58458 Witten, Germany
| | - Thomas Ostermann
- Department for Psychology and Psychotherapy, Witten/Herdecke University, 58458 Witten, Germany
- Correspondence:
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Peña-Martínez VM, Acosta-Olivo C, Tamez-Mata Y, Simental-Mendía LE, Blázquez-Saldaña J, Vilchez-Cavazos F, Simental-Mendía M. Normal saline injection produces a therapeutic effect in patients with plantar fasciitis: A systematic review and meta-analysis of randomized controlled trials. Foot Ankle Surg 2022; 28:1129-1138. [PMID: 35637108 DOI: 10.1016/j.fas.2022.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/15/2022] [Accepted: 04/20/2022] [Indexed: 02/04/2023]
Abstract
BACKGROUND Injectable therapies have been increasingly investigated to treat plantar fasciitis in randomized controlled trials (RCT) where normal saline injections are frequently used as placebo. The purpose was to quantify the effect of saline injections and compared against available minimal clinically important difference (MCID) criteria specific for plantar fasciitis to assess if changes were clinically meaningful. METHODS RCT including a placebo group (normal saline) and reporting changes in pain and functional outcomes in plantar fasciitis were identified through a search in MEDLINE, Embase, Web of Science, and Scopus to February 2022. PRISMA guidelines and a registered protocol (PROSPERO: CRD42020214035) were followed to conduct the study. RESULTS Pooled analysis of 13 RCT (379 subjects) included for analysis revealed a significant improvement on pain (P < .00001) and functional scores (P < .00001) after normal saline injections. These changes exceeded the established MCID criteria. CONCLUSIONS Normal saline injections in plantar fasciitis showed a therapeutic effect with statistically and clinically meaningful improvement when administered in the setting of an RCT for up to 12 months. The control of potential confounders influencing the effect of saline injections is required for future research.
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Affiliation(s)
- Víctor Manuel Peña-Martínez
- Universidad Autonoma de Nuevo Leon, Orthopedics and Traumatology Service, "Dr. José Eleuterio González" University Hospital, Monterrey, Mexico
| | - Carlos Acosta-Olivo
- Universidad Autonoma de Nuevo Leon, Orthopedics and Traumatology Service, "Dr. José Eleuterio González" University Hospital, Monterrey, Mexico
| | - Yadira Tamez-Mata
- Universidad Autonoma de Nuevo Leon, Orthopedics and Traumatology Service, "Dr. José Eleuterio González" University Hospital, Monterrey, Mexico
| | - Luis E Simental-Mendía
- Instituto Mexicano del Seguro Social, Biomedical Research Unit, Delegación Durango, Durango, Mexico
| | - Jaime Blázquez-Saldaña
- Universidad Autonoma de Nuevo Leon, Orthopedics and Traumatology Service, "Dr. José Eleuterio González" University Hospital, Monterrey, Mexico
| | - Félix Vilchez-Cavazos
- Universidad Autonoma de Nuevo Leon, Orthopedics and Traumatology Service, "Dr. José Eleuterio González" University Hospital, Monterrey, Mexico
| | - Mario Simental-Mendía
- Universidad Autonoma de Nuevo Leon, Orthopedics and Traumatology Service, "Dr. José Eleuterio González" University Hospital, Monterrey, Mexico.
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7
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Placebo administration for dry eye disease: a level I evidence based systematic review and meta-analysis. Int J Clin Pharm 2022; 44:1087-1101. [PMID: 35939178 PMCID: PMC9618542 DOI: 10.1007/s11096-022-01439-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Accepted: 06/04/2022] [Indexed: 12/05/2022]
Abstract
Background The efficacy of various common treatment options for dry eye disease (DED) has been investigated against placebo. However, the potential beneficial effect of placebo in the management of DED is still unclear. Aim This meta-analysis investigated the impact of placebo administration in DED in Ocular Surface Disease Index (OSDI), Schirmer I test (SIT), tear breakup time (TBUT), corneal staining, and complications. Method This meta-analysis and systematic review was conducted according to the 2020 PRISMA guidelines. In March 2022, Pubmed, Web of Science, Google Scholar, and Embase were accessed. All the randomised clinical trials which investigated any active treatment against a placebo control group were considered. The following data were extracted at baseline and at last follow-up: Ocular Surface Disease Index (OSDI), tear breakup time test (TBUT), Schirmer I test (SIT), corneal staining. Results Data from 56 studies (12,205 patients) were retrieved. Placebo administration is not effective in improving TBUT (P = 0.3), OSDI (P = 0.2), SIT (P = 0.1) and corneal staining (P = 0.1) from baseline to last follow-up. Active treatment led to a higher TBUT and SIT compared to placebo administration (P < 0.0001). The active treatment resulted in a lower OSDI compared to placebo administration (P = 0.0005). Five studies reported data on the corneal staining. No difference was found between placebo administration and active treatment (P = 0.8). Conclusion Placebo administration does not impact symptoms of DED and can be successfully employed to evaluate the efficacy of active treatments. Supplementary Information The online version contains supplementary material available at 10.1007/s11096-022-01439-y.
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Kamerman PR, Vollert J. Greater baseline pain inclusion criteria in clinical trials increase regression to the mean effect: a modelling study. Pain 2022; 163:e748-e758. [PMID: 34510140 DOI: 10.1097/j.pain.0000000000002468] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 08/24/2021] [Indexed: 11/26/2022]
Abstract
ABSTRACT We modelled the effects of pain intensity inclusion thresholds (3/10, 4/10, and 5/10 on a 0- to 10-point numerical pain rating scale) on the magnitude of the regression to the mean effect under conditions that were consistent with the sample mean and variance, and intermeasurement correlation observed in clinical trials for the management of chronic pain. All data were modelled on a hypothetical placebo control group. We found a progressive increase in the mean pain intensity as the pain inclusion threshold increased, but this increase was not uniform, having an increasing effect on baseline measurements compared with study endpoint measurements as the threshold was increased. That is, the regression to the mean effect was magnified by increasing inclusion thresholds. Furthermore, the effect increasing pain inclusion thresholds had on the regression to the mean effect was increased by decreasing sample mean values at baseline and intermeasurement correlations, and increasing sample variance. At its smallest, the regression to the mean effect was 0.13/10 (95% confidence interval: 0.03/10-0.24/10; threshold: 3/10, baseline mean pain: 6.5/10, SD: 1.6/10, and correlation: 0.44), and at its greatest, it was 0.78/10 (95% confidence interval: 0.63/10-0.94/10; threshold: 5/10, baseline mean pain: 6/10, SD: 1.8/10, and correlation: 0.19). We have shown that using pain inclusion thresholds in clinical trials drives progressively larger regression to the mean effects. We believe that a threshold of 3/10 offers the best compromise between maintaining assay sensitivity (the goal of thresholds) and the size of the regression to the mean effect.
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Affiliation(s)
- Peter R Kamerman
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, South Africa
| | - Jan Vollert
- Pain Research, Department of Surgery and Cancer (MSK), Imperial College London, London, United Kingdom
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital of Schleswig-Holstein, Campus Kiel, Germany
- Department of Anaesthesiology, Intensive Care, and Pain Medicine, University Hospital Muenster, Germany
- Neurophysiology, Mannheim Center of Translational Neuroscience (MCTN), Medical Faculty Mannheim, Heidelberg University, Germany
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Tiwari SR, Vigotsky AD, Apkarian AV. On the Relationship Between Pain Variability and Relief in Randomized Clinical Trials. FRONTIERS IN PAIN RESEARCH 2022; 3:844309. [PMID: 35465296 PMCID: PMC9024103 DOI: 10.3389/fpain.2022.844309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 03/11/2022] [Indexed: 11/30/2022] Open
Abstract
Previous research reports suggest greater baseline variability is associated with greater pain relief in those who receive a placebo. However, studies that evidence this association do not control for confounding effects from regression to the mean and natural history. In this report, we analyzed data from two randomized clinical trials (Placebo I and Placebo II, total N = 139) while adjusting for the effects of natural history and regression to the mean via a no treatment group. Results agree between the two placebo groups in each study: both placebo groups showed negligible semi-partial correlations between baseline variability and adjusted response [rsp (CI95%) = 0.22 (0.03, 0.42) and 0 (−0.07, 0.07) for Placebo I and II, respectively]. The no treatment group in Placebo I showed a negative correlation [−0.22 (−0.43, −0.02)], but the no treatment and drug groups in Placebo II's correlations were negligible [−0.02 (−0.08, 0.02) and 0.00 (−0.10, 0.12) for the no treatment and drug groups, respectively]. When modeled as a linear covariate, baseline pain variability accounted for <1% of the variance in post-intervention pain across both studies. Even after adjusting for baseline pain and natural history, the inability of baseline pain variability to account for substantial variance in pain response highlights that previous results concerning pain variability and treatment response may be inconsistent. Indeed, the relationship appears to be neither consistently specific nor sensitive to improvements in the placebo group. More work is needed to understand and establish the prognostic value of baseline pain variability—especially its placebo specificity and generalizability across patient populations.
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Affiliation(s)
- Siddharth R. Tiwari
- Illinois Mathematics and Science Academy, Aurora, IL, United States
- Center for Translational Pain Research, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Andrew D. Vigotsky
- Center for Translational Pain Research, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
- Departments of Biomedical Engineering and Statistics, Northwestern University, Evanston, IL, United States
| | - A. Vania Apkarian
- Center for Translational Pain Research, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
- Departments of Neuroscience, Anesthesia, and Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
- *Correspondence: A. Vania Apkarian
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Hengartner MP, Plöderl M. Estimates of the minimal important difference to evaluate the clinical significance of antidepressants in the acute treatment of moderate-to-severe depression. BMJ Evid Based Med 2022; 27:69-73. [PMID: 33593736 DOI: 10.1136/bmjebm-2020-111600] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/22/2021] [Indexed: 12/27/2022]
Abstract
The efficacy of antidepressants in the acute treatment of moderate-to-severe depression remains a controversial issue. The minimal important difference (MID) is relevant to judge the clinical significance of treatment effects. In this analysis paper, we discuss estimates of the MID for common depression outcome measures.For the Hamilton Depression Rating Scale 17-item Version (HDRS-17), according to both anchor-based and distribution-based approaches, MID estimates range from 3 to 8 points, and the most accurate values are likely between 3 and 5 points. For the 6-item version (HDRS-6), MID estimates range between 2 and 4 points. For both the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Beck Depression Inventory II (BDI-II), MID estimates range between 3 and 9 points, with estimates of 3-6 points likely being the most accurate. Quality of life appears to be more important to patients than core depression symptoms. We thus also evaluated the Short-Form 36 (SF-36) mental component score, a popular mental-health-related quality of life measure. Its MID estimate is likely about 5 points. By contrast, the average treatment effects of antidepressants on the HDRS-17, HDRS-6, MADRS, BDI-II and SF-36 are 2 points, 1.5 points, 3 points, 2 points and 3-5 points, respectively.In conclusion, the efficacy of antidepressants in the acute treatment of moderate-to-severe depression consistently fails to exceed the lower bound of the MID estimates for common depression outcome measures. The clinical significance of antidepressants thus remains uncertain and we call for more research on quality of life measures, which are the patients' most valued outcome domains.
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Affiliation(s)
- Michael P Hengartner
- Department of Applied Psychology, Zurich University of Applied Sciences, Zurich, Switzerland
| | - Martin Plöderl
- Department of Crisis Intervention and Suicide Prevention, Paracelsus Medical University Salzburg, Salzburg, Salzburg, Austria
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Abstract
A placebo is an inert substance normally used in clinical trials for comparison with an active substance. However, a placebo has been shown to have an effect on its own; commonly known as the placebo effect. A placebo is an essential component in the design of conclusive clinical trials but has itself become the focus of intense research. The placebo effect is partly the result of positive expectations of the recipient on the state of health. Conversely, a nocebo effect is when negative expectations from a substance lead to poor treatment outcomes and/or adverse events. Randomized controlled trials in functional urology have demonstrated the importance of the placebo and nocebo effects across different diseases such as overactive bladder, urinary incontinence, lower urinary tract symptoms and interstitial cystitis/painful bladder syndrome, as well as male and female sexual dysfunction. Understanding the true nature of the placebo-nocebo complex and the scope of its effect in functional urology could help urologists to maximize the positive effects of this phenomenon while minimizing its potentially negative effects.
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Côté P, Hartvigsen J, Axén I, Leboeuf-Yde C, Corso M, Shearer H, Wong J, Marchand AA, Cassidy JD, French S, Kawchuk GN, Mior S, Poulsen E, Srbely J, Ammendolia C, Blanchette MA, Busse JW, Bussières A, Cancelliere C, Christensen HW, De Carvalho D, De Luca K, Du Rose A, Eklund A, Engel R, Goncalves G, Hebert J, Hincapié CA, Hondras M, Kimpton A, Lauridsen HH, Innes S, Meyer AL, Newell D, O'Neill S, Pagé I, Passmore S, Perle SM, Quon J, Rezai M, Stupar M, Swain M, Vitiello A, Weber K, Young KJ, Yu H. The global summit on the efficacy and effectiveness of spinal manipulative therapy for the prevention and treatment of non-musculoskeletal disorders: a systematic review of the literature. Chiropr Man Therap 2021; 29:8. [PMID: 33596925 PMCID: PMC7890602 DOI: 10.1186/s12998-021-00362-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 01/01/2021] [Indexed: 12/15/2022] Open
Abstract
Background A small proportion of chiropractors, osteopaths, and other manual medicine providers use spinal manipulative therapy (SMT) to manage non-musculoskeletal disorders. However, the efficacy and effectiveness of these interventions to prevent or treat non-musculoskeletal disorders remain controversial. Objectives We convened a Global Summit of international scientists to conduct a systematic review of the literature to determine the efficacy and effectiveness of SMT for the primary, secondary and tertiary prevention of non-musculoskeletal disorders. Global summit The Global Summit took place on September 14–15, 2019 in Toronto, Canada. It was attended by 50 researchers from 8 countries and 28 observers from 18 chiropractic organizations. At the summit, participants critically appraised the literature and synthesized the evidence. Systematic review of the literature We searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, the Cumulative Index to Nursing and Allied Health, and the Index to Chiropractic Literature from inception to May 15, 2019 using subject headings specific to each database and free text words relevant to manipulation/manual therapy, effectiveness, prevention, treatment, and non-musculoskeletal disorders. Eligible for review were randomized controlled trials published in English. The methodological quality of eligible studies was assessed independently by reviewers using the Scottish Intercollegiate Guidelines Network (SIGN) criteria for randomized controlled trials. We synthesized the evidence from articles with high or acceptable methodological quality according to the Synthesis without Meta-Analysis (SWiM) Guideline. The final risk of bias and evidence tables were reviewed by researchers who attended the Global Summit and 75% (38/50) had to approve the content to reach consensus. Results We retrieved 4997 citations, removed 1123 duplicates and screened 3874 citations. Of those, the eligibility of 32 articles was evaluated at the Global Summit and 16 articles were included in our systematic review. Our synthesis included six randomized controlled trials with acceptable or high methodological quality (reported in seven articles). These trials investigated the efficacy or effectiveness of SMT for the management of infantile colic, childhood asthma, hypertension, primary dysmenorrhea, and migraine. None of the trials evaluated the effectiveness of SMT in preventing the occurrence of non-musculoskeletal disorders. Consensus was reached on the content of all risk of bias and evidence tables. All randomized controlled trials with high or acceptable quality found that SMT was not superior to sham interventions for the treatment of these non-musculoskeletal disorders. Six of 50 participants (12%) in the Global Summit did not approve the final report. Conclusion Our systematic review included six randomized clinical trials (534 participants) of acceptable or high quality investigating the efficacy or effectiveness of SMT for the treatment of non-musculoskeletal disorders. We found no evidence of an effect of SMT for the management of non-musculoskeletal disorders including infantile colic, childhood asthma, hypertension, primary dysmenorrhea, and migraine. This finding challenges the validity of the theory that treating spinal dysfunctions with SMT has a physiological effect on organs and their function. Governments, payers, regulators, educators, and clinicians should consider this evidence when developing policies about the use and reimbursement of SMT for non-musculoskeletal disorders. Supplementary Information The online version contains supplementary material available at 10.1186/s12998-021-00362-9.
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Affiliation(s)
- Pierre Côté
- Faculty of Health Sciences, Ontario Tech University, Oshawa, Canada. .,Centre for Disability Prevention and Rehabilitation at Ontario Tech University and CMCC, Oshawa, Canada. .,Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada. .,IHPME, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada.
| | - Jan Hartvigsen
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.,Nordic Institute of Chiropractic and Clinical Biomechanics, Odense, Denmark
| | - Iben Axén
- Intervention & Implementation Research for Worker Health, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.,ELIB - et liv i bevegelse, Oslo, Norway
| | - Charlotte Leboeuf-Yde
- Department for Regional Health Research, University of Southern Denmark, Odense, Denmark
| | - Melissa Corso
- Faculty of Health Sciences, Ontario Tech University, Oshawa, Canada.,Centre for Disability Prevention and Rehabilitation at Ontario Tech University and CMCC, Oshawa, Canada
| | - Heather Shearer
- Centre for Disability Prevention and Rehabilitation at Ontario Tech University and CMCC, Oshawa, Canada.,IHPME, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada
| | - Jessica Wong
- Faculty of Health Sciences, Ontario Tech University, Oshawa, Canada.,Centre for Disability Prevention and Rehabilitation at Ontario Tech University and CMCC, Oshawa, Canada.,Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada
| | - Andrée-Anne Marchand
- Department de Chiropractique, Université du Québec à Trois-Rivières, Trois-Rivières, Canada
| | - J David Cassidy
- Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada
| | - Simon French
- Department of Chiropractic, Faculty of Science and Engineering, Macquarie University, Sydney, Australia
| | - Gregory N Kawchuk
- Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Canada
| | - Silvano Mior
- Centre for Disability Prevention and Rehabilitation at Ontario Tech University and CMCC, Oshawa, Canada.,Canadian Memorial Chiropractic College, Toronto, Canada
| | - Erik Poulsen
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - John Srbely
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Canada
| | - Carlo Ammendolia
- IHPME, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada.,Rebecca MacDonald Centre, Mount Sinai Hospital, Toronto, Canada
| | - Marc-André Blanchette
- Department de Chiropractique, Université du Québec à Trois-Rivières, Trois-Rivières, Canada
| | - Jason W Busse
- Department of Health Research Methods, Evidence & Impact, Faculty of Health Sciences, McMaster University, Hamilton, Canada
| | - André Bussières
- Department de Chiropractique, Université du Québec à Trois-Rivières, Trois-Rivières, Canada.,School of Physical & Occupational Therapy, McGill University, Montreal, Canada
| | - Carolina Cancelliere
- Faculty of Health Sciences, Ontario Tech University, Oshawa, Canada.,Centre for Disability Prevention and Rehabilitation at Ontario Tech University and CMCC, Oshawa, Canada
| | | | - Diana De Carvalho
- Faculty of Medicine, Memorial University of Newfoundland, St. John's, Canada
| | - Katie De Luca
- Department of Chiropractic, Faculty of Science and Engineering, Macquarie University, Sydney, Australia
| | - Alister Du Rose
- Faculty of Life Sciences and Education University of South Wales, Cardiff, UK
| | - Andreas Eklund
- Intervention & Implementation Research for Worker Health, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Roger Engel
- Department of Chiropractic, Faculty of Science and Engineering, Macquarie University, Sydney, Australia
| | | | - Jeffrey Hebert
- Faculty of Kinesiology, University of New Brunswick, Fredericton, Canada
| | - Cesar A Hincapié
- Department of Chiropractic Medicine, Faculty of Medicine, University of Zurich & Balgrist University Hospital, Zurich, Switzerland
| | - Maria Hondras
- Department of Anesthesiology, University of Kansas Medical Center, Kansas City, USA
| | | | - Henrik Hein Lauridsen
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Stanley Innes
- College of Science, Health, Engineering and Education, Murdoch University, Murdoch, Australia
| | | | | | - Søren O'Neill
- Department for Regional Health Research, University of Southern Denmark, Odense, Denmark.,Spine Center of Southern Denmark, University Hospital of Southern Denmark, Middelfart, Denmark
| | - Isabelle Pagé
- Department de Chiropractique, Université du Québec à Trois-Rivières, Trois-Rivières, Canada
| | - Steven Passmore
- Faculty of Kinesiology & Recreation Management University of Manitoba, Winnipeg, Canada
| | - Stephen M Perle
- School of Chiropractic, University of Bridgeport, Bridgeport, USA
| | - Jeffrey Quon
- School of Population and Public Health, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Mana Rezai
- Centre for Disability Prevention and Rehabilitation at Ontario Tech University and CMCC, Oshawa, Canada
| | - Maja Stupar
- Canadian Memorial Chiropractic College, Toronto, Canada
| | - Michael Swain
- Department of Chiropractic, Faculty of Science and Engineering, Macquarie University, Sydney, Australia
| | - Andrew Vitiello
- School of Health, Medical and Applied Sciences, CQ University, Sydney, Australia
| | - Kenneth Weber
- Stanford University School of Medicine, Stanford University, Stanford, USA
| | - Kenneth J Young
- School of Sport and Health Sciences, University of Central Lancashire, Preston, England
| | - Hainan Yu
- Faculty of Health Sciences, Ontario Tech University, Oshawa, Canada.,Centre for Disability Prevention and Rehabilitation at Ontario Tech University and CMCC, Oshawa, Canada
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Murray EJ. Editorial: Demystifying the Placebo Effect. Am J Epidemiol 2021; 190:2-9. [PMID: 32719871 DOI: 10.1093/aje/kwaa162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 07/17/2020] [Accepted: 07/21/2020] [Indexed: 12/19/2022] Open
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14
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Acosta-Olivo CA, Millán-Alanís JM, Simental-Mendía LE, Álvarez-Villalobos N, Vilchez-Cavazos F, Peña-Martínez VM, Simental-Mendía M. Effect of Normal Saline Injections on Lateral Epicondylitis Symptoms: A Systematic Review and Meta-analysis of Randomized Clinical Trials. Am J Sports Med 2020; 48:3094-3102. [PMID: 32045280 DOI: 10.1177/0363546519899644] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Lateral epicondylitis, or tennis elbow, is a painful degenerative disorder that commonly occurs in adults between 40 and 60 years of age. Normal saline (NS) injections have been used as placebo through a large number of randomized controlled trials (RCTs) focused on the treatment of lateral epicondylitis. PURPOSE This meta-analysis of RCTs aimed to assess the therapeutic effect of NS injections on lateral epicondylitis symptoms and compare results with established minimal clinically important difference criteria. STUDY DESIGN Systematic review and meta-analysis. METHODS MEDLINE, Embase, Web of Science, and Scopus databases were searched for clinical trials reporting pain and joint function with the visual analog scale, Patient-Rated Tennis Elbow Evaluation, and Disabilities of the Arm, Shoulder and Hand in patients with lateral epicondylitis. The meta-analysis was conducted with a random effects model and generic inverse variance method. Heterogeneity was tested with the I2 statistic index. RESULTS A total of 15 RCTs included in this meta-analysis revealed a significant improvement in pain (mean difference, 3.61 cm [95% CI, 2.29-4.92 cm]; P < .00001; I2 = 88%; visual analog scale) and function (mean difference, 25.65 [95% CI, 13.30-37.99]; P < .0001; I2 = 82%; Patient-Rated Tennis Elbow Evaluation / Disabilities of the Arm, Shoulder and Hand) after NS injection (≥6 months). CONCLUSION NS injections yielded a statistically significant and clinically meaningful improvement in pain and functional outcomes in patients with lateral epicondylitis. New research should focus on better methods to diminish the potential confounders that could lead to this effect because NS injections could mask the real effect of an active therapeutic intervention in RCT. REGISTRATION CRD42019127547 (PROSPERO).
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Affiliation(s)
- Carlos Alberto Acosta-Olivo
- Universidad Autonoma de Nuevo Leon, Orthopedics and Traumatology Service, Facultad de Medicina y Hospital Universitario Dr José Eleuterio González, Monterrey, Mexico
| | - Juan Manuel Millán-Alanís
- Universidad Autonoma de Nuevo Leon, Plataforma Invest-KER Unit Mexico, Facultad de Medicina, Monterrey, Mexico
| | | | - Neri Álvarez-Villalobos
- Universidad Autonoma de Nuevo Leon, Plataforma Invest-KER Unit Mexico, Facultad de Medicina, Monterrey, Mexico
- Universidad Autonoma de Nuevo Leon, Clinical Research Unit, Facultad de Medicina y Hospital Universitario Dr José Eleuterio González, Monterrey, Mexico
- Knowledge and Evaluation Research Unit, Mayo Clinic, Rochester, Minnesota, USA
| | - Félix Vilchez-Cavazos
- Universidad Autonoma de Nuevo Leon, Orthopedics and Traumatology Service, Facultad de Medicina y Hospital Universitario Dr José Eleuterio González, Monterrey, Mexico
| | - Víctor Manuel Peña-Martínez
- Universidad Autonoma de Nuevo Leon, Orthopedics and Traumatology Service, Facultad de Medicina y Hospital Universitario Dr José Eleuterio González, Monterrey, Mexico
| | - Mario Simental-Mendía
- Universidad Autonoma de Nuevo Leon, Orthopedics and Traumatology Service, Facultad de Medicina y Hospital Universitario Dr José Eleuterio González, Monterrey, Mexico
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15
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Loder EW, McGeeney B. Disentangling placebo effects in the treatment of migraine. Nat Rev Neurol 2020; 16:657-658. [PMID: 32887960 DOI: 10.1038/s41582-020-0406-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Elizabeth W Loder
- Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA. .,Harvard Medical School, Boston, MA, USA. .,Graham Headache Center, Brigham and Women's Faulkner Hospital, Boston, MA, USA.
| | - Brian McGeeney
- Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA.,Graham Headache Center, Brigham and Women's Faulkner Hospital, Boston, MA, USA
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16
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Hengartner MP. Is there a genuine placebo effect in acute depression treatments? A reassessment of regression to the mean and spontaneous remission. BMJ Evid Based Med 2020; 25:46-48. [PMID: 30975717 DOI: 10.1136/bmjebm-2019-111161] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/21/2019] [Indexed: 02/01/2023]
Abstract
Regression to the mean and spontaneous improvements are rarely considered in interpretations of treatment trials for acute major depression. Here I suggest that regression to the mean and spontaneous remission may account for most improvements seen in placebo groups and also for a large proportion of variance in the acute treatment outcome of both antidepressant pharmacotherapy and psychotherapy. These findings have important implications for the interpretation of active treatments and placebo response in depression trials.
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17
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Baines G, Araklitis G, Flint R, Robinson D, Cardozo L. What affects the placebo effect? Eur J Obstet Gynecol Reprod Biol 2020; 246:134-137. [DOI: 10.1016/j.ejogrb.2020.01.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 01/13/2020] [Accepted: 01/20/2020] [Indexed: 11/27/2022]
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18
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Teira D. Placebo trials without mechanisms: How far can they go? STUDIES IN HISTORY AND PHILOSOPHY OF BIOLOGICAL AND BIOMEDICAL SCIENCES 2019; 77:101177. [PMID: 31221503 DOI: 10.1016/j.shpsc.2019.101177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 05/17/2019] [Accepted: 06/10/2019] [Indexed: 06/09/2023]
Abstract
In this paper, I suggest that placebo effects, as we know them today, should be understood as experimental phenomena, low-level regularities whose causal structure is grasped through particular experimental designs with little theoretical guidance. Focusing on placebo interventions with needles for pain reduction -one of the few placebo regularities that seems to arise in meta-analytical studies- I discuss the extent to which it is possible to decompose the different factors at play through more fine-grained randomized clinical trials. My sceptical argument is twofold. On the one hand, I argue that experiments alone are not enough to standardize interventions, and that it is necessary to include theories. On the other hand, I argue that the social interactions that seem to be part of placebo effects are difficult, if not impossible, to blind. Therefore, the measurement biases arising from the participants' reactivity to the experimental setup cannot be controlled for. Further decomposition of placebo effects requires a theoretical account of the existing experimental regularities that may guide further tests.
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Affiliation(s)
- David Teira
- Dpto. de Lógica, Historia y Filosofía de la ciencia, UNED, Senda del rey 7 | 28040, Madrid, Spain.
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19
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The effect of lid hygiene on the tear film and ocular surface, and the prevalence of Demodex blepharitis in university students. Cont Lens Anterior Eye 2019; 43:159-168. [PMID: 31548151 DOI: 10.1016/j.clae.2019.09.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 08/26/2019] [Accepted: 09/10/2019] [Indexed: 01/10/2023]
Abstract
AIM To evaluate the effect blepharitis lid cleansers have on the tear film and ocular surface, and to examine the prevalence of Demodex folliculorum in a young population. METHODS Forty-eight university students completed a randomised, controlled, investigator-masked, eight-week clinical trial. Three eyelid hygiene products were investigated: blepharitis eyelid cleanser (OCuSOFT® Lid Scrub® PLUS foam), diluted baby shampoo (10% Johnson's® No More Tears ®) and a tea-tree based face wash (dr.organic®). Cooled boiled water was used as a control. Subjects attended for four visits: baseline, two weeks, four weeks and eight weeks. At each visit, subjective symptoms, non-invasive tear break up time, ocular surface staining and Demodex folliculorum investigation were assessed to evaluate any positive or negative effect on the tear film and ocular surface. Osmolarity was also measured at baseline and week eight only. RESULTS The overall prevalence of Demodex folliculorum found at baseline was 15%. Subjective symptoms improved in all groups, including control. There was no significant difference in mean osmolarity between the groups or within each group after eight weeks. There was a significant increase in osmolarity inter-eye variability in the baby shampoo group (5.5 ± 5.4 vs 15.2 ± 9.5; p = 0.03). There was no significant change in non-invasive tear break up time or ocular surface staining demonstrated after eight weeks of eyelid hygiene. CONCLUSION A low prevalence of Demodex folliculorum can be found in a young population. All blepharitis lid cleansers used demonstrated subjective improvement in symptoms, with no negative effects on tear break-up time or ocular surface staining. The blepharitis eyelid cleanser and tea-tree based face wash revealed no adverse effect on mean osmolarity or inter-eye variability. Similarly, baby shampoo did not cause a significant increase in mean osmolarity, however, a significant increase in inter-eye variability was found; suggesting a possible increase in ocular surface inflammation.
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20
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Antonelli M, Donelli D. Reinterpreting homoeopathy in the light of placebo effects to manage patients who seek homoeopathic care: A systematic review. HEALTH & SOCIAL CARE IN THE COMMUNITY 2019; 27:824-847. [PMID: 30456773 DOI: 10.1111/hsc.12681] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 10/10/2018] [Accepted: 10/12/2018] [Indexed: 06/09/2023]
Abstract
Homoeopathy is widespread, and users claim to benefit from it. However, clear evidence of its efficacy over placebo is not available to date. As a consequence, a social separation between homoeopathy users and mainstream medicine exists, exposing these patients to many risks. Our primary objective is to assess homoeopathy efficacy by systematically reviewing existing systematic reviews and meta-analyses and to systematically review trials on open-label placebo (OLP) treatments. A secondary objective is to understand if homoeopathy as a whole may be considered as a placebo treatment. PubMed/Medline, Embase, Google Scholar, and Cochrane Library were systematically searched for systematic reviews and meta-analyses on homoeopathy efficacy, and 61 studies were included. Same databases plus Journal of Interdisciplinary Placebo Studies (JIPS) were also systematically searched for randomised controlled trials (RCTs) on OLP treatments, and 10 studies were included. Databases were searched up to 24 February 2018. Two authors independently screened all retrieved articles and selected studies eligible for inclusion. The quality of reviews of included studies was evaluated with a dedicated NIH tool in the first review, whereas the risk of bias of trials of included studies was assessed with the specific Cochrane tool in the second review. Qualitative syntheses show that homoeopathy efficacy can be considered comparable to placebo, and that OLP treatments may be effective in some health conditions. Placebo effects like placebo itself, treatment context, physician-patient relationship, and other nonspecific factors can define the idea of placebo treatments, which may be effective in some conditions. If homoeopathy efficacy is comparable to placebo, and if placebo treatments can be effective in some conditions, then homoeopathy as a whole may be considered as a placebo treatment. Reinterpreting homoeopathy as a placebo treatment would define limits and possibilities of this practice. This perspective shift suggests a strategy to manage patients who seek homoeopathic care and to reconcile them with mainstream medicine in a sustainable way.
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Affiliation(s)
- Michele Antonelli
- Department of Medicine and Surgery, Institute of Public Health, University of Parma, Parma, Italy
- Terme di Monticelli, Parma, Italy
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21
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Abstract
The placebo effect is a fascinating phenomenon in clinical practice. Studies have shown that there is a significant placebo effect in a wide range of medical conditions including psychiatric disorders. This article looks at the background of the placebo effect, defines the common terms used, describes the various hypotheses that have been put forward to explain this seemingly inexplicable phenomenon and also covers the issue of using placebos in research trials, highlighting the important ethical dilemmas involved. Throughout, specific emphasis is given to psychiatry.
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22
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Hyde AJ, May BH, Xue CC, Zhang AL. Variation in Placebo Effect Sizes in Clinical Trials of Oral Interventions for Management of the Behavioral and Psychological Symptoms of Dementia (BPSD): A Systematic Review and Meta-Analysis. Am J Geriatr Psychiatry 2017; 25:994-1008. [PMID: 28363357 DOI: 10.1016/j.jagp.2017.02.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 02/14/2017] [Accepted: 02/24/2017] [Indexed: 11/18/2022]
Abstract
Increasing placebo effect sizes over time have been reported in randomized controlled trials (RCTs) for outcomes related to psychiatric symptoms. The Neuropsychiatric Inventory (NPI) is a key outcome measure in clinical trials of the behavioral and psychological symptoms of dementia (BPSD). Accurate placebo effect size estimates for NPI are needed for sample size calculations in order to adequately power future studies. This study investigated variation in placebo effect sizes for NPI in RCTs testing oral interventions for BPSD. A search of PubMed was conducted in April 2016 for two-armed, double-blinded, placebo-controlled RCTs testing any oral intervention for management of BPSD using the NPI. Meta-analysis was conducted of baseline versus end of treatment placebo group data of included studies. Twenty-five RCTs published from 2000 to 2015 were included. Substantial variation in placebo effect sizes was detected. Participants in placebo groups showed greater improvements in recent studies compared with earlier studies. Subgroup analyses indicated robustness of this finding. From 2000 to 2008 there was no significant change in total NPI scores within placebo groups (12 studies; 1,056 participants), whereas from 2009 to 2015 there was significant improvement (mean difference: -2.68; 95% confidence interval: -4.38, -0.99; z = 3.10; p = 0.002, random effects; I2 = 76%; 13 studies; 1,170 participants). This increase in NPI effect sizes in placebo groups has important implications for power calculations for future clinical trials of BPSD. Effect size estimates for NPI need to be based on more recent studies.
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Affiliation(s)
- Anna J Hyde
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC 3083, Australia
| | - Brian H May
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC 3083, Australia
| | - Charlie Changli Xue
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC 3083, Australia
| | - Anthony L Zhang
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC 3083, Australia.
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Wartolowska KA, Gerry S, Feakins BG, Collins GS, Cook J, Judge A, Carr AJ. A meta-analysis of temporal changes of response in the placebo arm of surgical randomized controlled trials: an update. Trials 2017; 18:323. [PMID: 28701195 PMCID: PMC5508709 DOI: 10.1186/s13063-017-2070-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 06/27/2017] [Indexed: 12/04/2022] Open
Abstract
Background Temporal changes in the placebo arm of randomized controlled trials (RCTs) have not been thoroughly investigated, despite the fact that results of RCTs depend on the comparison between arms. Methods In this update of our earlier systematic review and meta-analysis, we set out to investigate the effect of assessment time and number of visits on the magnitude of change from baseline in the placebo arm of these trials. We used linear mixed-effects models to account for within-trial correlations. Results Across all 47 trials the magnitude of response in the placebo arm did not change with time (β = -0.0070, 95% CI -0.024, 0.010) or visit (β = -0.033, 95% CI -0.082, 0.017) and remained significantly different from baseline for at least 12 months or seven follow-up visits. Change in the placebo arm in trials with subjective outcomes was large (β0 = 0.68, 95% CI 0.53, 0.82) and relatively constant across time (β = -0.0042, 95% CI -0.024, 0.016) and visit (β = -0.029, 95% CI -0.089, 0.031), whereas in trials with objective outcomes the response was smaller (β0 = 0.28, 95% CI 0.11, 0.46) and diminished with time (β = -0.030, 95% CI -0.050, -0.010), but not with visit (β = -0.099, 95% CI -0.30, 0.11). For trials with assessed outcomes, there was no significant effect of time (β = -0.0071, 95% CI -0.026, 0.011) or visit (β = -0.032, 95% CI -0.33, 0.26); however, these results should be interpreted with caution due to the small number of studies, and high clinical heterogeneity between studies. In trials with pain as an outcome, the improvement was significant (β0 = 0.91, 95% CI 0.75, 1.07), but there was no effect of time (β = -0.013, 95% CI -0.06, 0.03) or visit (β = -0.045, 95% CI -0.16, 0.069), and pain ratings remained significantly different from baseline for 12 months or seven visits. Conclusions These results are consistent with our previous findings. In trials with subjective outcomes response in the placebo arm remains large and relatively constant for at least a year, which is interesting considering that this is an effect of a single application of an invasive procedure. The lack of effect of time and visit number on subjective outcomes raises further questions regarding whether the observed response is the result of placebo effect or the result of bias. Electronic supplementary material The online version of this article (doi:10.1186/s13063-017-2070-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Karolina A Wartolowska
- NIHR Oxford Musculoskeletal Biomedical Research Unit, Old Road, OX3 7LD, Oxford, UK. .,Botnar Institute of Musculoskeletal Sciences, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Old Road, OX3 7LD, Oxford, UK.
| | - Stephen Gerry
- Botnar Institute of Musculoskeletal Sciences, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Old Road, OX3 7LD, Oxford, UK.,Centre for Statistics in Medicine, University of Oxford, Windmill Road, OX3 7LD, Oxford, UK
| | - Benjamin G Feakins
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Woodstock Road, OX2 6GG, Oxford, UK
| | - Gary S Collins
- Botnar Institute of Musculoskeletal Sciences, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Old Road, OX3 7LD, Oxford, UK.,Centre for Statistics in Medicine, University of Oxford, Windmill Road, OX3 7LD, Oxford, UK
| | - Jonathan Cook
- NIHR Oxford Musculoskeletal Biomedical Research Unit, Old Road, OX3 7LD, Oxford, UK.,Botnar Institute of Musculoskeletal Sciences, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Old Road, OX3 7LD, Oxford, UK
| | - Andrew Judge
- NIHR Oxford Musculoskeletal Biomedical Research Unit, Old Road, OX3 7LD, Oxford, UK.,Botnar Institute of Musculoskeletal Sciences, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Old Road, OX3 7LD, Oxford, UK.,MRC Lifecourse Epidemiology Unit, University of Southampton, University Road, SO17 1BJ, Southampton, UK
| | - Andrew J Carr
- NIHR Oxford Musculoskeletal Biomedical Research Unit, Old Road, OX3 7LD, Oxford, UK.,Botnar Institute of Musculoskeletal Sciences, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Old Road, OX3 7LD, Oxford, UK
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Novack GD, Asbell P, Barabino S, Bergamini MVW, Ciolino JB, Foulks GN, Goldstein M, Lemp MA, Schrader S, Woods C, Stapleton F. TFOS DEWS II Clinical Trial Design Report. Ocul Surf 2017; 15:629-649. [PMID: 28736344 PMCID: PMC8557254 DOI: 10.1016/j.jtos.2017.05.009] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 05/06/2017] [Indexed: 12/17/2022]
Abstract
The development of novel therapies for Dry Eye Disease (DED) is formidable, and relatively few treatments evaluated have been approved for marketing. In this report, the Subcommittee reviewed challenges in designing and conducting quality trials, with special reference to issues in trials in patients with DED and present the regulatory perspective on DED therapies. The Subcommittee reviewed the literature and while there are some observations about the possible reasons why so many trials have failed, there is no obvious single reason other than the lack of correlation between signs and symptoms in DED. Therefore the report advocates for conducting good quality studies, as described, going forward. A key recommendation for future studies is conduct consistent with Good Clinical Practice (GCP), including use of Good Manufacturing Practice (GMP) quality clinical trial material. The report also recommends that the design, treatments, and sample size be consistent with the investigational treatment, the objectives of the study, and the phase of development. Other recommendations for pivotal studies are a priori selection of the outcome measure, and an appropriate sample size.
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Affiliation(s)
- Gary D Novack
- Pharma Logic Development, San Rafael, CA, USA; Departments of Pharmacology and Ophthalmology, University of California, Davis, School of Medicine, CA, USA.
| | - Penny Asbell
- Department of Ophthalmology, Icahn School of Medicine at Mt Sinai, New York, NY, USA
| | | | - Michael V W Bergamini
- Nicox Ophthalmics, Inc., Fort Worth, TX, USA; University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Joseph B Ciolino
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Gary N Foulks
- Emeritus Professor of Ophthalmology, University of Louisville School of Medicine, Louisville, KY, USA
| | - Michael Goldstein
- Department of Ophthalmology, New England Medical Center and Tufts University, Boston, MA, USA
| | - Michael A Lemp
- Department of Ophthalmology, School of Medicine, Georgetown University, Washington, DC, USA
| | - Stefan Schrader
- Department of Ophthalmology, Heinrich-Heine University, Düsseldorf, Germany
| | - Craig Woods
- Deakin Optometry, School of Medicine, Deakin University, Geelong, Australia
| | - Fiona Stapleton
- School of Optometry and Vision Science, UNSW Australia, Sydney, NSW, Australia
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Imanaka T, Sato I, Tanaka S, Kawakami K. Predictive factors for the placebo effect in clinical trials for dry eye: a pooled analysis of three clinical trials. Br J Ophthalmol 2017; 101:1471-1474. [PMID: 28315833 DOI: 10.1136/bjophthalmol-2016-309887] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Revised: 01/30/2017] [Accepted: 02/28/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND Placebo effect is one of the methodological difficulties in dry eye clinical trials. If we could elucidate the tendencies of the placebo response and find predictors, we could reduce the placebo response in clinical trials for dry eye. In this study, we investigated the predictive factors for the placebo effect in dry eye clinical trials. METHODS A total of 205 patients with dry eye assigned to the placebo arms of three placebo-controlled randomised clinical trials were analysed by simple and multivariable regression analysis. The corneal fluorescein (FL) staining score and dry eye symptoms were studied at week 4. The variables of interest included gender, age, complications of Sjögren's syndrome, Schirmer's test I value, tear break-up time and conjunctival hyperaemia score. We also conducted a stratified analysis according to the patients' age. RESULTS Among all the studied endpoints, the baseline scores were significantly related to the corresponding placebo response. In addition, for the FL score and the dryness score, age was a significant predictor of the placebo response (p=0.04 and p<0.0001, respectively). Stratified analysis by age showed that patients more than 40 years of age are more likely to have a stronger placebo response in the FL and dryness scores. CONCLUSION The baseline scores and age were predictive factors of the placebo response in frequently used endpoints, such as FL score or dryness symptoms. These patient characteristics can be controlled by study design, and our findings enable the design of more efficient placebo-controlled studies with good statistical power.
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Affiliation(s)
- Takahiro Imanaka
- Department of Pharmacoepidemiology, Graduate School of Medicine, Kyoto University, Yoshida Konoecho, Sakyoku, Kyoto, Japan.,Research and Development Division, Santen Pharmaceutical Co., Ltd., Ofuka-cho, Kita-ku, Osaka, Japan
| | - Izumi Sato
- Department of Pharmacoepidemiology, Graduate School of Medicine, Kyoto University, Yoshida Konoecho, Sakyoku, Kyoto, Japan.,The Keihanshin Consortium for Fostering the Next Generation of Global Leaders in Research (K-CONNEX)
| | - Shiro Tanaka
- Department of Pharmacoepidemiology, Graduate School of Medicine, Kyoto University, Yoshida Konoecho, Sakyoku, Kyoto, Japan
| | - Koji Kawakami
- Department of Pharmacoepidemiology, Graduate School of Medicine, Kyoto University, Yoshida Konoecho, Sakyoku, Kyoto, Japan
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Is the perceived placebo effect comparable between adults and children? A meta-regression analysis. Pediatr Res 2017; 81:11-17. [PMID: 27648807 DOI: 10.1038/pr.2016.181] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 07/15/2016] [Indexed: 11/09/2022]
Abstract
BACKGROUND A potential larger perceived placebo effect in children compared with adults could influence the detection of the treatment effect and the extrapolation of the treatment benefit from adults to children. This study aims to explore this potential difference, using a meta-epidemiological approach. METHODS A systematic review of the literature was done to identify trials included in meta-analyses evaluating a drug intervention with separate data for adults and children. The standardized mean change and the proportion of responders (binary outcomes) were used to calculate the perceived placebo effect. A meta-regression analysis was conducted to test for the difference between adults and children of the perceived placebo effect. RESULTS For binary outcomes, the perceived placebo effect was significantly more favorable in children compared with adults (β = 0.13; P = 0.001). Parallel group trials (β = -1.83; P < 0.001), subjective outcomes (β = -0.76; P < 0.001), and the disease type significantly influenced the perceived placebo effect. CONCLUSION The perceived placebo effect is different between adults and children for binary outcomes. This difference seems to be influenced by the design, the disease, and outcomes. Calibration of new studies for children should consider cautiously the placebo effect in children.
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Dieppe P, Goldingay S, Greville-Harris M. The power and value of placebo and nocebo in painful osteoarthritis. Osteoarthritis Cartilage 2016; 24:1850-1857. [PMID: 27338671 DOI: 10.1016/j.joca.2016.06.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 05/13/2016] [Accepted: 06/11/2016] [Indexed: 02/02/2023]
Abstract
This paper reviews some recent advances in our understanding of the effects of sham or dummy interventions on pain and other symptoms in osteoarthritis (OA), and outlines two new approaches to the investigation of placebo and nocebo effects. We argue that the placebo effect provides us with a valuable way of investigating the nature of conditions like OA. For example, by examining which symptoms, biochemical markers or imaging features do or do not respond to placebo, we might learn more about the relationships between pathology and symptoms in OA. Placebo and nocebo effects are positive or negative outcomes resulting from the human interactions and contexts in which healthcare consultations take place. Subtle changes in behaviours and the environments in which consultations take place can have major effects on pain and other symptoms being experienced by people with OA. Nocebo effects are particularly powerful, leading to many health-care professionals (HCPs) causing unintended harm to their clients. Based on our own research, we conclude that beneficial outcomes are most likely to occur when both the (HCP) and the client feel safe and relaxed, and when the experiences of the client are validated by the (HCP). These findings have important implications for clinical practice. We believe that research in this field needs to be 'trans-disciplinary', escaping from the constraints of the purely biomedical, deterministic, positivist paradigm of most medical research. We provide the example of our own work which combines performance studies and scholarship, with psychology and medicine.
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Affiliation(s)
- P Dieppe
- University of Exeter Medical School, Room 2.34, South Cloisters, St Luke's Campus, University of Exeter, Heavitree Road, Exeter EX1 2LU, UK.
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Probiotic supplementation does not improve eradication rate of Helicobacter pylori infection compared to placebo based on standard therapy: a meta-analysis. Sci Rep 2016; 6:23522. [PMID: 26997149 PMCID: PMC4800733 DOI: 10.1038/srep23522] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 03/04/2016] [Indexed: 12/13/2022] Open
Abstract
This meta-analysis included eligible randomized controlled trials (RCTs) with the aim of determining whether probiotic supplementation can improve H. pylori eradication rates. PUBMED, EBSCO, Web of Science, and Ovid databases were searched. We included RCTs that investigated the effect of combining probiotics, with or without a placebo, with standard therapy. A total of 21 RCTs that reported standard therapy plus probiotics were included. Compared to the placebo group, the probiotics group was 1.21(OR 1.21, 95% CI: 0.86, 1.69) and 1.28 (OR 1.28, 95% CI: 0.88, 1.86) times more likely to achieve eradication of H. pylori infection in intent-to-treat (ITT) analysis and per protocol (PP) analysis, respectively. Probiotics with triple therapy plus a 14-day course of treatment did not improve the eradication of H. pylori infection (OR 1.44, 95% CI: 0.87, 2.39) compared to the placebo. Moreover, the placebo plus standard therapy did not improve eradication rates compared to standard therapy alone (P = 0.816). However, probiotics did improve the adverse effects of diarrhea and nausea. These pooled data suggest that the use of probiotics plus standard therapy does not improve the eradication rate of H. pylori infection compared to the placebo.
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Lilienfeld SO, Ritschel LA, Lynn SJ, Cautin RL, Latzman RD. Why Ineffective Psychotherapies Appear to Work: A Taxonomy of Causes of Spurious Therapeutic Effectiveness. PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2015; 9:355-87. [PMID: 26173271 DOI: 10.1177/1745691614535216] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The past 40 years have generated numerous insights regarding errors in human reasoning. Arguably, clinical practice is the domain of applied psychology in which acknowledging and mitigating these errors is most crucial. We address one such set of errors here, namely, the tendency of some psychologists and other mental health professionals to assume that they can rely on informal clinical observations to infer whether treatments are effective. We delineate four broad, underlying cognitive impediments to accurately evaluating improvement in psychotherapy-naive realism, confirmation bias, illusory causation, and the illusion of control. We then describe 26 causes of spurious therapeutic effectiveness (CSTEs), organized into a taxonomy of three overarching categories: (a) the perception of client change in its actual absence, (b) misinterpretations of actual client change stemming from extratherapeutic factors, and (c) misinterpretations of actual client change stemming from nonspecific treatment factors. These inferential errors can lead clinicians, clients, and researchers to misperceive useless or even harmful psychotherapies as effective. We (a) examine how methodological safeguards help to control for different CSTEs, (b) delineate fruitful directions for research on CSTEs, and (c) consider the implications of CSTEs for everyday clinical practice. An enhanced appreciation of the inferential problems posed by CSTEs may narrow the science-practice gap and foster a heightened appreciation of the need for the methodological safeguards afforded by evidence-based practice.
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Affiliation(s)
| | - Lorie A Ritschel
- Department of Psychiatry, University of North Carolina at Chapel Hill 3C Institute, Cary, NC
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Tomasik J, Yolken RH, Bahn S, Dickerson FB. Immunomodulatory Effects of Probiotic Supplementation in Schizophrenia Patients: A Randomized, Placebo-Controlled Trial. Biomark Insights 2015; 10:47-54. [PMID: 26052224 PMCID: PMC4454091 DOI: 10.4137/bmi.s22007] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 01/26/2015] [Accepted: 02/01/2015] [Indexed: 12/16/2022] Open
Abstract
Although peripheral immune system abnormalities have been linked to schizophrenia pathophysiology, standard antipsychotic drugs show limited immunological effects. Thus, more effective treatment approaches are required. Probiotics are microorganisms that modulate the immune response of the host and, therefore, may be beneficial to schizophrenia patients. The aim of this study was to examine the possible immunomodulatory effects of probiotic supplementation in chronic schizophrenia patients. The concentrations of 47 immune-related serum proteins were measured using multiplexed immunoassays in samples collected from patients before and after 14 weeks of adjuvant treatment with probiotics (Lactobacillus rhamnosus strain GG and Bifidobacterium animalis subsp. lactis strain Bb12; n = 31) or placebo (n = 27). Probiotic add-on treatment significantly reduced levels of von Willebrand factor (vWF) and increased levels of monocyte chemotactic protein-1 (MCP-1), brain-derived neurotrophic factor (BDNF), RANTES, and macrophage inflammatory protein-1 beta (MIP-1) beta with borderline significance (P ≤ 0.08). In silico pathway analysis revealed that probiotic-induced alterations are related to regulation of immune and intestinal epithelial cells through the IL-17 family of cytokines. We hypothesize that supplementation of probiotics to schizophrenia patients may improve control of gastrointestinal leakage.
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Affiliation(s)
- Jakub Tomasik
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK. ; Department of Neuroscience, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Robert H Yolken
- Stanley Division of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sabine Bahn
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK. ; Department of Neuroscience, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Faith B Dickerson
- Stanley Research Program at Sheppard Pratt, Sheppard Pratt Health System, Baltimore, MD, USA
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Yu R, Chen L. The need to control for regression to the mean in social psychology studies. Front Psychol 2015; 5:1574. [PMID: 25620951 PMCID: PMC4287101 DOI: 10.3389/fpsyg.2014.01574] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 12/19/2014] [Indexed: 11/13/2022] Open
Abstract
It is common in repeated measurements for extreme values at the first measurement to approach the mean at the subsequent measurement, a phenomenon called regression to the mean (RTM). If RTM is not fully controlled, it will lead to erroneous conclusions. The wide use of repeated measurements in social psychology creates a risk that an RTM effect will influence results. However, insufficient attention is paid to RTM in most social psychological research. Notable cases include studies on the phenomena of social conformity and unrealistic optimism (Klucharev et al., 2009, 2011; Sharot et al., 2011, 2012b; Campbell-Meiklejohn et al., 2012; Kim et al., 2012; Garrett and Sharot, 2014). In Study 1, 13 university students rated and re-rated the facial attractiveness of a series of female faces as a test of the social conformity effect (Klucharev et al., 2009). In Study 2, 15 university students estimated and re-estimated their risk of experiencing a series of adverse life events as a test of the unrealistic optimism effect (Sharot et al., 2011). Although these studies used methodologies similar to those used in earlier research, the social conformity and unrealistic optimism effects were no longer evident after controlling for RTM. Based on these findings we suggest several ways to control for the RTM effect in social psychology studies, such as adding the initial rating as a covariate in regression analysis, selecting a subset of stimuli for which the participant' initial ratings were matched across experimental conditions, and using a control group.
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Affiliation(s)
- Rongjun Yu
- Department of Psychology, School of Psychology and Center for Studies of Psychological Application, South China Normal University Guangzhou, China ; Scientific Laboratory of Economic Behaviors, School of Economics and Management, South China Normal University Guangzhou, China
| | - Li Chen
- Department of Psychology, School of Psychology and Center for Studies of Psychological Application, South China Normal University Guangzhou, China ; Scientific Laboratory of Economic Behaviors, School of Economics and Management, South China Normal University Guangzhou, China
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Heapy A, Dziura J, Buta E, Goulet J, Kulas JF, Kerns RD. Using Multiple Daily Pain Ratings to Improve Reliability and Assay Sensitivity: How Many Is Enough? THE JOURNAL OF PAIN 2014; 15:1360-5. [DOI: 10.1016/j.jpain.2014.09.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 09/09/2014] [Accepted: 09/19/2014] [Indexed: 10/24/2022]
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Böhm M, Linz D, Ukena C, Esler M, Mahfoud F. Renal Denervation for the Treatment of Cardiovascular High Risk-Hypertension or Beyond? Circ Res 2014; 115:400-9. [DOI: 10.1161/circresaha.115.302522] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Michael Böhm
- From the Klinik für Innere Medizin III, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany (M.B., D.L., C.U., F.M.); and Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (M.E.)
| | - Dominik Linz
- From the Klinik für Innere Medizin III, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany (M.B., D.L., C.U., F.M.); and Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (M.E.)
| | - Christian Ukena
- From the Klinik für Innere Medizin III, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany (M.B., D.L., C.U., F.M.); and Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (M.E.)
| | - Murray Esler
- From the Klinik für Innere Medizin III, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany (M.B., D.L., C.U., F.M.); and Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (M.E.)
| | - Felix Mahfoud
- From the Klinik für Innere Medizin III, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany (M.B., D.L., C.U., F.M.); and Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (M.E.)
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Arnold MH, Finniss DG, Kerridge I. Medicine's inconvenient truth: the placebo and nocebo effect. Intern Med J 2014; 44:398-405. [DOI: 10.1111/imj.12380] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Accepted: 12/29/2013] [Indexed: 12/19/2022]
Affiliation(s)
- M. H. Arnold
- Northern Clinical School; Sydney Medical School; University of Sydney; Sydney New South Wales Australia
- Centre for Values; Ethics and the Law in Medicine; School of Public Health; University of Sydney; Sydney New South Wales Australia
- Department of Rheumatology; Royal North Shore Hospital; Sydney New South Wales Australia
| | - D. G. Finniss
- Pain Management Research Institute; University of Sydney and Royal North Shore Hospital; Sydney New South Wales Australia
- School of Rehabilitation Sciences; Griffith University; Brisbane Queensland Australia
| | - I. Kerridge
- Northern Clinical School; Sydney Medical School; University of Sydney; Sydney New South Wales Australia
- Centre for Values; Ethics and the Law in Medicine; School of Public Health; University of Sydney; Sydney New South Wales Australia
- Haematology Department; Royal North Shore Hospital; Sydney New South Wales Australia
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Howard JP, Nowbar AN, Francis DP. Size of blood pressure reduction from renal denervation: insights from meta-analysis of antihypertensive drug trials of 4,121 patients with focus on trial design: the CONVERGE report. Heart 2013; 99:1579-87. [PMID: 24038167 DOI: 10.1136/heartjnl-2013-304238] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
OBJECTIVE 30 mm Hg drops in office systolic blood pressure are reported in trials of renal denervation, but ambulatory reductions are much smaller. This disparity is assumed to have a physiological basis and also be present with antihypertensive drugs. DESIGN We examine this office-ambulatory discrepancy through meta-analysis of drug and denervation trials, categorising by trial design. PATIENTS (STUDIES) 31 drug trials enrolling 4121 patients and 23 renal denervation trials enrolling 720 patients met the criteria. RESULTS In drug trials without randomisation or blinding, pressure reductions are 5.6 mm Hg (95% CI 2.98 to 8.22 mm Hg) larger on office measurements than ambulatory blood pressure monitoring (p<0.0001). By contrast, with randomisation and blinding, office reductions are identical to ambulatory reductions (difference -0.88 mm Hg, 95% CI -3.18 to 1.43, p=0.45). For renal denervation, there are no randomised blinded trial results. In unblinded trials, office pressure drops were 27.6 mm Hg versus pretreatment, and 26.6 mm Hg versus unintervened controls. By contrast, ambulatory pressure drops averaged 15.7 mm Hg across all trials. Among those where the baseline ambulatory pressure was not the deciding factor for enrolment (avoiding regression to the mean), ambulatory drops averaged only 11.9 mm Hg. CONCLUSIONS Discrepancies in drug trials between office and ambulatory blood pressure reductions disappear once double-blinded placebo control is implemented. Renal denervation trials may also undergo similar evolution. We predict that as denervation trial designs gradually improve in bias-resistance, office and ambulatory pressure drops will converge. We predict that it is the office drops that will move to match the ambulatory drops, that is, not 30, but nearer 13.
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Affiliation(s)
- James P Howard
- International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, , London, UK
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Reduction in intraocular pressure after cataract extraction: the Ocular Hypertension Treatment Study. Ophthalmology 2012; 119:1826-31. [PMID: 22608478 DOI: 10.1016/j.ophtha.2012.02.050] [Citation(s) in RCA: 208] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 02/02/2012] [Accepted: 02/28/2012] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To determine the change in intraocular pressure (IOP) after cataract extraction in the observation group of the Ocular Hypertension Treatment Study. DESIGN Comparative case series. PARTICIPANTS Forty-two participants (63 eyes) who underwent cataract surgery in at least 1 eye during the study and a control group of 743 participants (743 eyes) who did not undergo cataract surgery. METHODS We defined the "split date" as the study visit date at which cataract surgery was reported in the cataract surgery group and a corresponding date in the control group. Preoperative IOP was defined as the mean IOP of up to 3 visits before the split date. Postoperative IOP was the mean IOP of up to 3 visits including the split date (0, 6, and 12 months' with "0 months" equaling the split date). In both groups, we censored data after initiation of ocular hypotensive medication or glaucoma surgery of any kind. MAIN OUTCOME MEASURES Difference in preoperative and postoperative IOP. RESULTS In the cataract group, postoperative IOP was significantly lower than the preoperative IOP (19.8 ± 3.2 mmHg vs. 23.9 ± 3.2 mmHg; P<0.001). The postoperative IOP remained lower than the preoperative IOP for at least 36 months. The average decrease in postoperative IOP from preoperative IOP was 16.5%, and 39.7% of eyes had postoperative IOP ≥ 20% below preoperative IOP. A greater reduction in postoperative IOP occurred in the eyes with the highest preoperative IOP. In the control group, the corresponding mean IOPs were 23.8 ± 3.6 before the split date and 23.4 ± 3.9 after the split date. CONCLUSIONS Cataract surgery decreases IOP in patients with ocular hypertension over a long period of time.
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Geers AL, Wellman JA, Fowler SL, Rasinski HM, Helfer SG. Placebo expectations and the detection of somatic information. J Behav Med 2011; 34:208-17. [PMID: 21046445 PMCID: PMC3088785 DOI: 10.1007/s10865-010-9301-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Accepted: 10/09/2010] [Indexed: 01/03/2023]
Abstract
In a laboratory study we examined the hypothesis that placebo expectations enhance the initial identification of placebo-relevant sensations over placebo-irrelevant sensations. Participants (N = 102) were randomly assigned to one of three expectation groups. In the first group, participants ingested a placebo capsule and were told it was caffeine (deceptive expectation). In a second group, participants ingested a placebo capsule and were told it may be caffeine or it may be a placebo (double-blind expectation). Participants in the third group were given no expectation. All participants then tallied the placebo-relevant and placebo-irrelevant sensations they experienced during a 7-min period. Participants in the deceptive expectation group identified more placebo-relevant sensations than placebo-irrelevant sensations. No-expectation participants identified more placebo-irrelevant sensations than placebo-relevant sensations. Participants given the double-blind expectation identified an equal amount of placebo-relevant and irrelevant sensations. The amount of both placebo-relevant and placebo-irrelevant sensations detected mediated the relationship between the expectation manipulation and subsequent symptom reports. These data support the position that expectations cause placebo responding, in part, by altering how one identifies bodily sensations.
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Affiliation(s)
- Andrew L Geers
- Department of Psychology, University of Toledo, Toledo, OH 43606-3390, USA.
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Abstract
By definition, complementary and alternative medicine (CAM) attempts to diagnose and treat illnesses in unconventional ways. CAM has been classified as: (1) alternative medical systems (eg, traditional Chinese medicine [including acupuncture], naturopathic medicine, ayurvedic medicine, and homeopathy); (2) biologic-based therapies (eg, herbal, special dietary, and individual biologic treatments); (3) energy therapies (eg, Reiki, therapeutic touch, magnet therapy, Qi Gong, and intercessory prayer); (4) manipulative and body-based systems (eg, chiropractic, osteopathy, and massage); and (5) mind-body interventions (eg, meditation, biofeedback, hypnotherapy, and the relaxation response). This review focuses on how to assess the effectiveness of CAM therapies for chronic musculoskeletal pains, emphasizing the role of specific and nonspecific analgesic mechanisms, including placebo.
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Affiliation(s)
- Roland Staud
- Department of Medicine, University of Florida College of Medicine, Gainesville, FL 32610-0221, USA.
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Kato MT, Kogawa EM, Santos CN, Conti PCR. TENS and low-level laser therapy in the management of temporomandibular disorders. J Appl Oral Sci 2009; 14:130-5. [PMID: 19089044 PMCID: PMC4327455 DOI: 10.1590/s1678-77572006000200012] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Pain relief and reestablishment of normal jaw function are the main goals of conservative management of Temporomandibular Disorders (TMD). Transcutaneous electrical nerve stimulation (TENS) and laser therapy are part of these modalities, although little is known about their real efficacy in controlled studies. This research compared these two treatments in a sample of 18 patients with chronic TMD of muscular origin, divided into two groups (LASER and TENS). Treatment consisted of ten sessions, in a period of 30 days. Active range of motion (AROM), visual analogue scale (VAS) of pain and muscle (masseter and anterior temporalis) palpation were used for follow-up analysis. Data were analyzed by Friedman test and ANOVA for repeated measurements. Results showed decrease in pain and increase in AROM for both groups (p<0.05), and improvement in muscle tenderness for the LASER group. Authors concluded that both therapies are effective as part of TMD management and a cumulative effect may be responsible for the improvement. Caution is suggested when analyzing these results because of the self-limiting feature of musculoskeletal conditions like TMD.
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Affiliation(s)
- Melissa Thiemi Kato
- Public Health Department, Bauru Dental School - University of São Paulo, Bauru - SP, Brasil
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Hartman SE. Why do ineffective treatments seem helpful? A brief review. CHIROPRACTIC & OSTEOPATHY 2009; 17:10. [PMID: 19822008 PMCID: PMC2770065 DOI: 10.1186/1746-1340-17-10] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Accepted: 10/12/2009] [Indexed: 11/11/2022]
Abstract
After any therapy, when symptoms improve, healthcare providers (and patients) are tempted to award credit to treatment. Over time, a particular treatment can seem so undeniably helpful that scientific verification of efficacy is judged an inconvenient waste of time and resources. Unfortunately, practitioners' accumulated, day-to-day, informal impressions of diagnostic reliability and clinical efficacy are of limited value. To help clarify why even treatments entirely lacking in direct effect can seem helpful, I will explain why real signs and symptoms often improve, independent of treatment. Then, I will detail quirks of human perception, interpretation, and memory that often make symptoms seem improved, when they are not. I conclude that healthcare will grow to full potential only when judgments of clinical efficacy routinely are based in properly scientific, placebo-controlled, outcome analysis.
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Affiliation(s)
- Steve E Hartman
- Department of Anatomy, College of Osteopathic Medicine, University of New England, Biddeford, Maine 04005, USA.
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Doherty M, Dieppe P. The "placebo" response in osteoarthritis and its implications for clinical practice. Osteoarthritis Cartilage 2009; 17:1255-62. [PMID: 19410027 DOI: 10.1016/j.joca.2009.03.023] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Accepted: 03/22/2009] [Indexed: 02/02/2023]
Abstract
Many observations support a major biological effect from the way in which people interpret the meaning of each component of their medical experience and the context in which this occurs. A recent systematic review of randomised controlled trials in osteoarthritis has demonstrated that the effect size of "placebo" is substantial and is usually greater than that obtained from the specific effect of an individual treatment. In the context of a randomised controlled trial, such a large placebo or "meaning" response is considered a nuisance, but in the context of clinical practice the optimisation of such meaning and contextual responses, through enhanced "care", could greatly benefit people who suffer from osteoarthritis.
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Affiliation(s)
- M Doherty
- University of Nottingham, Nottingham, UK.
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da Cunha LA, Firoozmand LM, da Silva AP, Camargo SEA, Esteves SA, Oliveira W. Efficacy of low-level laser therapy in the treatment of temporomandibular disorder. Int Dent J 2008; 58:213-7. [PMID: 18783114 DOI: 10.1111/j.1875-595x.2008.tb00351.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
AIMS To evaluate the effectiveness of low-level laser therapy (LLLT) in patients presenting with temporomandibular disorder (TMD) in a random and placebo-controlled research design. METHODS The sample consisted of 40 patients, divided into an experimental group (G1) and a placebo group (G2). The treatment was done with an infrared laser (830nm, 500mW, 20s, 4J/point) at the painful points, once a week for four consecutive weeks. The patients were evaluated before and after the treatment through a Visual Analogue Scale (VAS) and the Craniomandibular Index (CMI). RESULTS The baseline and posttherapy values of VAS and CMI were compared by the paired T-test, separately for the placebo and laser groups. A significant difference was observed between initial and final values (p < 0.05) in both groups. Baseline and post-therapy values of pain and CMI were compared in the therapy groups by the two-sample T-test, yet no significant differences were observed regarding VAS and CMI (p > 0.05). CONCLUSION After either placebo or laser therapy, pain and temporomandibular symptoms were significantly lower, although there was no significant difference between groups. The low-level laser therapy was not effective in the treatment of TMD, when compared to the placebo.
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Oken BS. Placebo effects: clinical aspects and neurobiology. Brain 2008; 131:2812-23. [PMID: 18567924 PMCID: PMC2725026 DOI: 10.1093/brain/awn116] [Citation(s) in RCA: 155] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Revised: 04/28/2008] [Accepted: 05/04/2008] [Indexed: 01/31/2023] Open
Abstract
Placebo effects are beneficial health outcomes not related to the relatively direct biological effects of an intervention and can be elicited by an agent that, by itself, is inert. Understanding these placebo effects will help to improve clinical trial design, especially for interventions such as surgery, CNS-active drugs and behavioural interventions which are often non-blinded. A literature review was performed to retrieve articles discussing placebo implications of clinical trials, the neurobiology of placebo effects and the implications of placebo effect for several disorders of neurological relevance. Recent research in placebo analgesia and other conditions has demonstrated that several neurotransmitter systems, such as opiate and dopamine, are involved with the placebo effect. Brain regions including anterior cingulate cortex, dorsolateral prefrontal cortex and basal ganglia have been activated following administration of placebo. A patient's expectancy of improvement may influence outcomes as much as some active interventions and this effect may be greater for novel interventions and for procedures. Maximizing this expectancy effect is important for clinicians to optimize the health of their patient. There have been many relatively acute placebo studies that are now being extended into clinically relevant models of placebo effect.
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Affiliation(s)
- Barry S Oken
- Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA.
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Oken BS, Flegal K, Zajdel D, Kishiyama S, Haas M, Peters D. Expectancy effect: Impact of pill administration on cognitive performance in healthy seniors. J Clin Exp Neuropsychol 2007; 30:7-17. [DOI: 10.1080/13803390701775428] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Barry S. Oken
- a Department of Neurology , Oregon Health & Science University , Portland, OR, USA
- b Department of Behavioral Neuroscience , Oregon Health & Science University , Portland, OR, USA
| | - Kristin Flegal
- a Department of Neurology , Oregon Health & Science University , Portland, OR, USA
| | - Daniel Zajdel
- a Department of Neurology , Oregon Health & Science University , Portland, OR, USA
| | - Shirley Kishiyama
- a Department of Neurology , Oregon Health & Science University , Portland, OR, USA
| | - Mitchell Haas
- c Center for Outcome Studies, Western States Chiropractic College , Portland, OR, USA
| | - Dawn Peters
- d Department of Public Health and Preventive Medicine , Oregon Health & Science University , Portland, OR, USA
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Sievenpiper JL, Ezatagha A, Dascalu A, Vuksan V. When a placebo is not a 'placebo': a placebo effect on postprandial glycaemia. Br J Clin Pharmacol 2007; 64:546-9. [PMID: 17509038 PMCID: PMC2048544 DOI: 10.1111/j.1365-2125.2007.02929.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
AIMS Placebo effects in clinical trials remain uncertain. To investigate a placebo effect on acute postprandial plasma glucose, we conducted a follow-up investigation on a previous study. METHODS The effect of placebo (9 g encapsulated cornstarch +500 ml water, taken at -40 min) on the plasma glucose response to a 75-g oral glucose tolerance test (OGTT) was assessed in a previous study in 12 healthy subjects (gender, five male, seven female; age 27 +/- 6 years; body mass index 24 +/- 3.4 kg m(-2)). This was compared with the effect of a water control (500 ml water taken alone at -40 min) on the same outcome in the same subjects in a follow-up study. RESULTS Cornstarch placebo decreased plasma glucose area under the curve during the 75-g OGTT by 28% [Delta (95% confidence interval) -63.3 min mmol(-1) l(-1) (-218.33, 91.66), P < 0.02] compared with the water control (P < 0.05). CONCLUSIONS Postprandial plasma glucose outcomes may be vulnerable to placebo effects.
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Affiliation(s)
- John L Sievenpiper
- Risk Factor Modification Centre, St Michael's Hospital and Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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