Related Experiment Video
Updated: May 21, 2026
08:36
The Adjuvant Efficacy of Angong Niuhuang Pill in the Treatment of Viral Encephalitis: A Meta-Analysis of Randomized Controlled Trials
Published on: April 19, 2024
Concordance between target trial emulation and randomised controlled trials: systematic review and meta-analysis
Canlong Wang1, Dongfeng Tang1, Peter von Dadelszen1,2
1School of Life Course and Population Sciences, King's College London, London, UK.
BMJ (Clinical Research Ed.)
|May 19, 2026
Summary
Target trial emulations show moderate agreement with randomized controlled trials. Improving emulation design, especially using linked databases, can enhance result concordance for health interventions.
Area of Science:
- Epidemiology
- Health Research Methodology
- Comparative Effectiveness Research
Background:
- Target trial emulation (TTE) is increasingly used to mimic randomized controlled trials (RCTs) using observational data.
- Assessing the concordance between TTEs and their benchmark RCTs is crucial for validating TTEs.
- Understanding factors influencing TTE success is vital for reliable real-world evidence generation.
Purpose of the Study:
- To evaluate the agreement between paired TTEs and their corresponding RCTs.
- To identify key factors that determine the success and accuracy of TTEs.
Main Methods:
- Systematic review and meta-analysis of observational studies emulating RCTs.
- Searched Medline, EMBASE, Scopus, PsycINFO, and Web of Science (2010-2025).
- Assessed concordance using Pearson correlation, standardized difference agreement, and ratio of ratios for 21 emulation design features.
Main Results:
- Overall moderate concordance (Pearson r=0.59) between 107 TTE-RCT pairs.
- Closer emulation of trial design (63 pairs) showed higher agreement (Pearson r=0.83).
- Systematic underestimation of treatment effects for cardiovascular events (RoR=0.76) and overestimation for respiratory outcomes (RoR=1.20) were observed. Claims data emulations also underestimated effects (RoR=0.90).
Conclusions:
- Current TTEs achieve moderate concordance with RCTs.
- Improved emulation design, including better baseline and outcome emulation and use of multisource linked databases, can enhance concordance.
- Findings highlight areas for methodological improvement in real-world evidence generation through TTE.
Related Concept Videos
01:12Hazard Ratio
The hazard ratio (HR) is a widely used measure in clinical trials to compare the risk of events, such as death or disease recurrence, between two groups over time. It reflects the ratio of hazard rates—the instantaneous risk of the event occurring—between a treatment group and a control group. This measure provides valuable insights into the relative effectiveness of a treatment by assessing how the risk of an event differs between the two groups.
For example, in a clinical trial evaluating a...
For example, in a clinical trial evaluating a...
01:11Clinical Trials: Overview
Clinical development focuses on how the drug will interact with the human body and encompasses four key phases of clinical trials, each serving a specific purpose in assessing the safety and effectiveness of new drugs. These phases overlap and build upon one another. Phase I involves a small group of healthy volunteers (typically 20-80 individuals) or, in cases where significant toxicity is expected, patients with the targeted disease, such as cancer or AIDS. The volunteers are tested for...
01:16Clinical Trials
Clinical trials are prospective experimental studies conducted on humans to determine the safety and efficacy of treatments, drugs, diet methods, and medical devices. Using statistics in clinical trials enables researchers to derive reasonable and accurate conclusions from the collected data, allowing them to make wise decisions in uncertain situations. In medical research, statistical methods are crucial for preventing errors and bias.
There are four phases in a clinical trial. A phase one...
There are four phases in a clinical trial. A phase one...
01:11Blinding
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.
01:20Bioequivalence Experimental Study Designs: Completely Randomized and Randomized Block Designs
Bioequivalence experimental study designs are crucial methodologies used in evaluating and comparing the bioavailability of different drug products. These designs are categorized into various types: completely randomized, randomized block, repeated measures, cross and carry-over, and Latin square designs.Completely randomized designs involve randomly allocating treatments to all subjects participating in the experiment. This allocation is achieved by assigning unique random numbers to subjects...
01:23Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
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, controlled...
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast, controlled...