Related Experiment Video
Updated: Jul 25, 2025
08:50
How to Study Placebo Responses in Motion Sickness with a Rotation Chair Paradigm in Healthy Participants
Published on: December 14, 2014
9.3K
When does the placebo effect have an impact on network meta-analysis results?
Adriani Nikolakopoulou1, Anna Chaimani2, Toshi A Furukawa3
1Institute of Medical Biometry and Statistics, Faculty of Medicine and Medical Center - University of Freiburg, Freiburg, Germany adriani.nikolakopoulou@uniklinik-freiburg.de.
BMJ Evidence-Based Medicine
|June 29, 2023
Summary
The placebo effect, driven by patient belief, can bias randomized controlled trial results. This study identifies red flags for placebo bias in meta-analyses, using component network meta-analysis to estimate placebo effects.
Area of Science:
- Clinical Trials Methodology
- Evidence Synthesis
- Psychotherapy Research
Background:
- The placebo effect, arising from simulated treatment expectations, significantly impacts subjective symptom evaluation in clinical trials.
- Factors like blinding quality and study design can influence placebo response and introduce bias into randomized controlled trials (RCTs).
- This bias can propagate into systematic reviews, affecting pairwise and network meta-analyses.
Purpose of the Study:
- To identify indicators ('red flags') of potential placebo effect bias in pairwise and network meta-analyses.
- To explore the estimation of placebo effects using component network meta-analysis.
- To apply these methods to a real-world dataset examining depression psychotherapies.
Main Methods:
- Utilized component network meta-analysis to quantify placebo effects.
- Analyzed a published network meta-analysis on depression treatments, including 123 studies.
- Examined the influence of study characteristics on placebo response and potential bias.
Main Results:
- Demonstrated the application of component network meta-analysis for estimating placebo effects.
- Provided a framework for identifying potential biases in meta-analyses due to placebo responses.
- The analysis focused on the relative effectiveness of psychotherapies versus control treatments for depression.
Conclusions:
- Placebo effects can significantly bias meta-analysis results, necessitating careful consideration in evidence synthesis.
- Component network meta-analysis offers a valuable tool for estimating and understanding placebo effects.
- Identifying and addressing placebo bias is crucial for accurate interpretation of treatment effectiveness in systematic reviews.
More Related Videos
Related Concept Videos
01:54The Placebo Effect
6.2K
The placebo effect occurs when people's expectations or beliefs influence or determine their experience in a given situation. In other words, simply expecting something to happen can actually make it happen.
6.2K
02:07Blind Procedures
10.7K
Ideally, the people who observe and record the children’s behavior are unaware of who was assigned to the experimental or control group, in order to control for experimenter bias. Experimenter bias refers to the possibility that a researcher’s expectations might skew the results of the study. Remember, conducting an experiment requires a lot of planning, and the people involved in the research project have a vested interest in supporting their hypotheses. If the observers knew which...
10.7K
01:11Blinding
2.5K
Blinding is a commonly used method of not telling participants which treatment a subject is receiving. Blinding is a critical part of a randomized control trial or RCT. It reduces the bias that affects the results. In an RCT, blinding is used in the form of a placebo. A placebo effect occurs when untreated subjects falsely believe they have received the treatment and report improved symptoms. A placebo or a dummy treatment is administered to subjects to negate the bias caused by such an effect.
2.5K
01:23Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
148
Biopharmaceutical studies constitute a vital field aiming to enhance drug delivery methods and refine therapeutic approaches, drawing upon diverse interdisciplinary knowledge. In research methodologies, the choice between controlled and non-controlled studies significantly influences the study's reliability and accuracy.
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast,...
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast,...
148
01:52Regression Toward the Mean
6.3K
Regression toward the mean (“RTM”) is a phenomenon in which extremely high or low values—for example, and individual’s blood pressure at a particular moment—appear closer to a group’s average upon remeasuring. Although this statistical peculiarity is the result of random error and chance, it has been problematic across various medical, scientific, financial and psychological applications. In particular, RTM, if not taken into account, can interfere when...
6.3K
01:29Bias in Epidemiological Studies
369
Biases can arise at various stages of research, from study design and data collection to analysis and interpretation. Recognizing and addressing these biases is essential to ensure the validity and reliability of epidemiological findings.Broadly speaking, biases in epidemiology fall into three main categories: selection bias, information bias, and confounding. A more detailed description of possible biases is:
369